Life

Most terrestrial plants and animals left the ocean a single time in their evolutionary history to live ashore. But crabs have seemingly scuttled out of the sea more than a dozen times, with at least two groups later reverting back to a marine lifestyle, a study finds.

The research, published November 6 in Systematic Biology, sheds new light on the evolutionary history of the group Brachyura, which includes roughly 7,600 species of “true crabs,” and includes the most comprehensive evolutionary tree yet created for the group. And the study offers clues about how other early invertebrates may have evolved a terrestrial lifestyle, researchers say.

.email-conversion {
border: 1px solid #ffcccb;
color: white;
margin-top: 50px;
background-image: url(“/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg”);
padding: 20px;
clear: both;
}

.zephr-registration-form{max-width:440px;margin:20px auto;padding:20px;background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form *{box-sizing:border-box}.zephr-registration-form-text > *{color:var(–zephr-color-text-main)}.zephr-registration-form-relative-container{position:relative}.zephr-registration-form-flex-container{display:flex}.zephr-registration-form-input.svelte-blfh8x{display:block;width:100%;height:calc(var(–zephr-input-height) * 1px);padding-left:8px;font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input.svelte-blfh8x::placeholder{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-checkbox.svelte-blfh8x{width:auto;height:auto;margin:8px 5px 0 0;float:left}.zephr-registration-form-input-radio.svelte-blfh8x{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x{width:50px;padding:0;border-radius:50%}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch{border:none;border-radius:50%;padding:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch-wrapper{border:none;border-radius:50%;padding:0}.zephr-registration-form-input.disabled.svelte-blfh8x,.zephr-registration-form-input.disabled.svelte-blfh8x:hover{border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);background-color:var(–zephr-color-background-tinted)}.zephr-registration-form-input.error.svelte-blfh8x{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-label.svelte-1ok5fdj.svelte-1ok5fdj{margin-top:10px;display:block;line-height:30px;font-size:12px;color:var(–zephr-color-text-tinted);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj{display:block}.zephr-registration-form-button.svelte-17g75t9{height:calc(var(–zephr-button-height) * 1px);line-height:0;padding:0 20px;text-decoration:none;text-transform:capitalize;text-align:center;border-radius:calc(var(–zephr-button-borderRadius) * 1px);font-size:calc(var(–zephr-button-fontSize) * 1px);font-weight:normal;cursor:pointer;border-style:solid;border-width:calc(var(–zephr-button-borderWidth) * 1px);border-color:var(–zephr-color-action-tinted);transition:backdrop-filter 0.2s, background-color 0.2s;margin-top:20px;display:block;width:100%;background-color:var(–zephr-color-action-main);color:#fff;position:relative;overflow:hidden;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-button.svelte-17g75t9:hover{background-color:var(–zephr-color-action-tinted);border-color:var(–zephr-color-action-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled:hover{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-text.svelte-i1fi5{font-size:19px;text-align:center;margin:20px auto;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-divider-container.svelte-mk4m8o{display:flex;align-items:center;justify-content:center;margin:40px 0}.zephr-registration-form-divider-line.svelte-mk4m8o{height:1px;width:50%;margin:0 5px;background-color:var(–zephr-color-text-tinted);;}.zephr-registration-form-divider-text.svelte-mk4m8o{margin:0 12px;color:var(–zephr-color-text-main);font-size:14px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);white-space:nowrap}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message.svelte-179421u{text-align:center;padding:10px 30px;border-radius:5px;font-size:15px;margin-top:10px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message-title.svelte-179421u{font-weight:bold;margin-bottom:10px}.zephr-registration-form-response-message-success.svelte-179421u{background-color:#baecbb;border:1px solid #00bc05}.zephr-registration-form-response-message-error.svelte-179421u{background-color:#fcdbec;border:1px solid #d90c00}.zephr-registration-form-social-sign-in.svelte-gp4ky7{align-items:center}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7{height:55px;padding:0 15px;color:#000;background-color:#fff;box-shadow:0px 0px 5px rgba(0, 0, 0, 0.3);border-radius:10px;font-size:17px;display:flex;align-items:center;cursor:pointer;margin-top:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7:hover{background-color:#fafafa}.zephr-registration-form-social-sign-in-icon.svelte-gp4ky7{display:flex;justify-content:center;margin-right:30px;width:25px}.zephr-form-link-message.svelte-rt4jae{margin:10px 0 10px 20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-tcs.svelte-1wyy3bx{margin:20px 0 0 0;font-size:15px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-inline.svelte-1wyy3bx{margin:20px 0 0 0}.zephr-registration-form-progress-bar.svelte-8qyhcl{width:100%;border:0;border-radius:20px;margin-top:10px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-bar{background-color:var(–zephr-color-background-tinted);border:0;border-radius:20px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-value{background-color:var(–zephr-color-text-tinted);border:0;border-radius:20px}.zephr-registration-progress-bar-step.svelte-8qyhcl{margin:auto;color:var(–zephr-color-text-tinted);font-size:12px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-progress-bar-step.svelte-8qyhcl:first-child{margin-left:0}.zephr-registration-progress-bar-step.svelte-8qyhcl:last-child{margin-right:0}.zephr-registration-form-input-error-text.svelte-19a73pq{color:var(–zephr-color-warning-main);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-select.svelte-19a73pq{display:block;appearance:auto;width:100%;height:calc(var(–zephr-input-height) * 1px);font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-color-text-main);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;padding:10px}.zephr-registration-form-input-select.disabled.svelte-19a73pq{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.unselected.svelte-19a73pq{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.error.svelte-19a73pq{border-color:var(–zephr-color-warning-main)}.zephr-registration-form-input-textarea.svelte-19a73pq{background-color:#fff;border:1px solid #ddd;color:#222;font-size:14px;font-weight:300;padding:16px;width:100%}.zephr-registration-form-input-slider-output.svelte-19a73pq{margin:13px 0 0 10px}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.spin.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 2s 0s infinite linear}.pulse.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 1s infinite steps(8)}@keyframes svelte-1cj2gr0-spin{0%{transform:rotate(0deg)}100%{transform:rotate(360deg)}}.zephr-registration-form-checkbox.svelte-1gzpw2y{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-checkbox-label.svelte-1gzpw2y{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-checkmark.svelte-1gzpw2y{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid var(–zephr-color-text-main);border-radius:6px;margin-right:12px;cursor:pointer}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y{border-color:#009fe3}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y:after{content:””;position:absolute;width:6px;height:13px;border:solid #009fe3;border-width:0 2px 2px 0;transform:rotate(45deg);top:3px;left:8px;box-sizing:border-box}.zephr-registration-form-checkmark.disabled.svelte-1gzpw2y{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-checkmark.disabled.checked.svelte-1gzpw2y:after{border:solid var(–zephr-color-background-tinted);border-width:0 2px 2px 0}.zephr-registration-form-checkmark.error.svelte-1gzpw2y{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-radio.svelte-1qn5n0t{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-radio-label.svelte-1qn5n0t{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-radio-dot.svelte-1qn5n0t{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid #ebebeb;border-radius:50%;margin-right:12px}.checked.svelte-1qn5n0t{border-color:#009fe3}.checked.svelte-1qn5n0t:after{content:””;position:absolute;width:17px;height:17px;background:#009fe3;background:linear-gradient(#009fe3, #006cb5);border-radius:50%;top:2px;left:2px}.disabled.checked.svelte-1qn5n0t:after{background:var(–zephr-color-background-tinted)}.error.svelte-1qn5n0t{border:1px solid var(–zephr-color-warning-main)}.zephr-form-link.svelte-64wplc{margin:10px 0;color:#6ba5e9;text-decoration:underline;cursor:pointer;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-form-link-disabled.svelte-64wplc{color:var(–zephr-color-text-main);cursor:none;text-decoration:none}.zephr-registration-form-google-icon.svelte-1jnblvg{width:20px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}
.zephr-registration-form {
max-width: 100%;
background-image: url(/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg);
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
margin: 0px auto;
margin-bottom: 4rem;
padding: 20px;
}

.zephr-registration-form-text h6 {
font-size: 0.8rem;
}

.zephr-registration-form h4 {
font-size: 3rem;
}

.zephr-registration-form h4 {
font-size: 1.5rem;
}

.zephr-registration-form-button.svelte-17g75t9:hover {
background-color: #fc6a65;
border-color: #fc6a65;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9:disabled {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9 {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-text > * {
color: #FFFFFF;
font-weight: bold
font: 25px;
}
.zephr-registration-form-progress-bar.svelte-8qyhcl {
width: 100%;
border: 0;
border-radius: 20px;
margin-top: 10px;
display: none;
}
.zephr-registration-form-response-message-title.svelte-179421u {
font-weight: bold;
margin-bottom: 10px;
display: none;
}
.zephr-registration-form-response-message-success.svelte-179421u {
background-color: #8db869;
border: 1px solid #8db869;
color: white;
margin-top: -0.2rem;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(1){
font-size: 18px;
text-align: center;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(5){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(7){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(9){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj {
display: none;
color: white;
}
.zephr-registration-form-input.disabled.svelte-blfh8x, .zephr-registration-form-input.disabled.svelte-blfh8x:hover {
border: calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);
background-color: white;
}
.zephr-registration-form-checkbox-label.svelte-1gzpw2y {
display: flex;
align-items: center;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
font-size: 20px;
margin-bottom: -20px;
}

Unlike for well-studied animals such as birds and mammals, a unified crab tree of life has been lacking, says Kristin Hultgren, an invertebrate zoologist at Seattle University. “While the authors have developed a useful framework for understanding the complexity of transitioning to terrestrial life, one of the most important contributions is the extensive, well-dated evolutionary tree.”

Crabs are an extremely diverse group and have colonized nearly every type of habitat on Earth. It’s been a challenge to study when crabs first shifted from one habitat to another during evolution because, like some other invertebrates, crabs don’t have the extensive fossil trail that early vertebrates do, says Joanna Wolfe, an evolutionary biologist at Harvard University.

Past research has also often treated marine, freshwater and land crabs as discrete subgroups when they’re more like a continuum, Wolfe says. “They’re not distinct and actually have a lot in common, and looking at them together helps trace their evolution.”

Wolfe and her colleagues collected genetic data from 333 species of crabs in the group Brachyura. These crustaceans are evolutionarily distinct from, although closely related to, another group of crustaceans that independently evolved crablike bodies and are often erroneously referred to as crabs, including animals like the hermit and king crabs.

The team then combined that genetic data with dozens of fossils to generate a crab evolutionary tree, layering on details about each species’ life history and adaptations for living on land to reconstruct a possible timeline of when crabs colonized drier ground.

True crabs diverged from other crustacean lineages roughly 230 million years ago during the Triassic Period, the researchers found, refining previous estimates. Over the next hundred or so million years, brachyurans diversified widely during a period previously dubbed the “Cretaceous crab revolution.”

The study also showed that during their evolution, crabs appear to have adapted to a more terrestrial lifestyle as many as 17 times, either by shifting from the ocean to the intertidal zone or similarly salty habitats like mangroves, or by colonizing freshwater estuaries and rivers on route to land. In at least two cases, crabs reverted to a marine lifestyle long after they’d left.

The amount of times that crabs independently left the ocean is “astonishing,” says Katie Davis, an evolutionary paleobiologist at the University of York in England who was not involved in the research. “And it’s really fantastic that molecular biology, fossils and modern numerical techniques can be combined to provide insight into previously unanswerable questions.”

The study also hints at what other early arthropods that ventured onto the land may have been like, Wolfe says. Past studies have shown that crabs and insects share a common, if unknown, aquatic ancestor. By looking at the types of crabs that successfully left the ocean, it’s possible to guess at what adaptations early insects might have needed to do the same. Modern crabs living out of the water today, for example, excel at keeping themselves from drying out and have limited their dependence on water for reproduction.

“If you’re going to be the first proto-insect to come out of the ocean … you’re probably going to need those kinds of adaptations,” Wolfe says. More

Four decades ago, warm waters from an El Niño event killed off nearly all the corals surrounding the Galápagos. Most coral reefs never recovered (SN: 1/9/15). But in recent months, researchers have discovered vast landscapes of thriving corals in deeper waters surrounding the equatorial islands.

In April, scientists documented the first pristine deep coral reef found in the region, dubbed Cacho De Coral, which sits atop the ridge of an underwater volcano and stretches about 250 meters. On October 26, a second team announced the discovery of an even bigger reef, this one more than 800 meters long, spanning the length of eight football fields.  

With coral reefs around the globe in peril due to climate change, the finds are a small piece of good news (SN: 8/9/23). These newfound reefs within the Galápagos Islands Marine Reserve have so far been protected from human influence and the direct impacts of warming waters.

Brittle stars and shrimps are among the creatures living in and around a newly discovered reef west of the Galápagos’ Fernandina Island.Schmidt Ocean Institute

The newest reef was discovered when oceanographer Stuart Banks and colleagues set out on a 30-day expedition to explore parts of the ocean using a remotely operated robot named SuBastian. While in the Galápagos Islands Marine Reserve, which included a visit to Cacho De Coral, the team spotted a second reef.

“It’s like coming into your house and realizing that you’ve got a basement that you never knew was there,” says Banks, of the Charles Darwin Research Station on Santa Cruz Island in the Galápagos. “And it’s full of really cool stuff.”

.email-conversion {
border: 1px solid #ffcccb;
color: white;
margin-top: 50px;
background-image: url(“/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg”);
padding: 20px;
clear: both;
}

.zephr-registration-form{max-width:440px;margin:20px auto;padding:20px;background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form *{box-sizing:border-box}.zephr-registration-form-text > *{color:var(–zephr-color-text-main)}.zephr-registration-form-relative-container{position:relative}.zephr-registration-form-flex-container{display:flex}.zephr-registration-form-input.svelte-blfh8x{display:block;width:100%;height:calc(var(–zephr-input-height) * 1px);padding-left:8px;font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input.svelte-blfh8x::placeholder{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-checkbox.svelte-blfh8x{width:auto;height:auto;margin:8px 5px 0 0;float:left}.zephr-registration-form-input-radio.svelte-blfh8x{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x{width:50px;padding:0;border-radius:50%}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch{border:none;border-radius:50%;padding:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch-wrapper{border:none;border-radius:50%;padding:0}.zephr-registration-form-input.disabled.svelte-blfh8x,.zephr-registration-form-input.disabled.svelte-blfh8x:hover{border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);background-color:var(–zephr-color-background-tinted)}.zephr-registration-form-input.error.svelte-blfh8x{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-label.svelte-1ok5fdj.svelte-1ok5fdj{margin-top:10px;display:block;line-height:30px;font-size:12px;color:var(–zephr-color-text-tinted);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj{display:block}.zephr-registration-form-button.svelte-17g75t9{height:calc(var(–zephr-button-height) * 1px);line-height:0;padding:0 20px;text-decoration:none;text-transform:capitalize;text-align:center;border-radius:calc(var(–zephr-button-borderRadius) * 1px);font-size:calc(var(–zephr-button-fontSize) * 1px);font-weight:normal;cursor:pointer;border-style:solid;border-width:calc(var(–zephr-button-borderWidth) * 1px);border-color:var(–zephr-color-action-tinted);transition:backdrop-filter 0.2s, background-color 0.2s;margin-top:20px;display:block;width:100%;background-color:var(–zephr-color-action-main);color:#fff;position:relative;overflow:hidden;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-button.svelte-17g75t9:hover{background-color:var(–zephr-color-action-tinted);border-color:var(–zephr-color-action-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled:hover{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-text.svelte-i1fi5{font-size:19px;text-align:center;margin:20px auto;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-divider-container.svelte-mk4m8o{display:flex;align-items:center;justify-content:center;margin:40px 0}.zephr-registration-form-divider-line.svelte-mk4m8o{height:1px;width:50%;margin:0 5px;background-color:var(–zephr-color-text-tinted);;}.zephr-registration-form-divider-text.svelte-mk4m8o{margin:0 12px;color:var(–zephr-color-text-main);font-size:14px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);white-space:nowrap}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message.svelte-179421u{text-align:center;padding:10px 30px;border-radius:5px;font-size:15px;margin-top:10px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message-title.svelte-179421u{font-weight:bold;margin-bottom:10px}.zephr-registration-form-response-message-success.svelte-179421u{background-color:#baecbb;border:1px solid #00bc05}.zephr-registration-form-response-message-error.svelte-179421u{background-color:#fcdbec;border:1px solid #d90c00}.zephr-registration-form-social-sign-in.svelte-gp4ky7{align-items:center}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7{height:55px;padding:0 15px;color:#000;background-color:#fff;box-shadow:0px 0px 5px rgba(0, 0, 0, 0.3);border-radius:10px;font-size:17px;display:flex;align-items:center;cursor:pointer;margin-top:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7:hover{background-color:#fafafa}.zephr-registration-form-social-sign-in-icon.svelte-gp4ky7{display:flex;justify-content:center;margin-right:30px;width:25px}.zephr-form-link-message.svelte-rt4jae{margin:10px 0 10px 20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-tcs.svelte-1wyy3bx{margin:20px 0 0 0;font-size:15px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-inline.svelte-1wyy3bx{margin:20px 0 0 0}.zephr-registration-form-progress-bar.svelte-8qyhcl{width:100%;border:0;border-radius:20px;margin-top:10px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-bar{background-color:var(–zephr-color-background-tinted);border:0;border-radius:20px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-value{background-color:var(–zephr-color-text-tinted);border:0;border-radius:20px}.zephr-registration-progress-bar-step.svelte-8qyhcl{margin:auto;color:var(–zephr-color-text-tinted);font-size:12px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-progress-bar-step.svelte-8qyhcl:first-child{margin-left:0}.zephr-registration-progress-bar-step.svelte-8qyhcl:last-child{margin-right:0}.zephr-registration-form-input-error-text.svelte-19a73pq{color:var(–zephr-color-warning-main);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-select.svelte-19a73pq{display:block;appearance:auto;width:100%;height:calc(var(–zephr-input-height) * 1px);font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-color-text-main);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;padding:10px}.zephr-registration-form-input-select.disabled.svelte-19a73pq{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.unselected.svelte-19a73pq{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.error.svelte-19a73pq{border-color:var(–zephr-color-warning-main)}.zephr-registration-form-input-textarea.svelte-19a73pq{background-color:#fff;border:1px solid #ddd;color:#222;font-size:14px;font-weight:300;padding:16px;width:100%}.zephr-registration-form-input-slider-output.svelte-19a73pq{margin:13px 0 0 10px}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.spin.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 2s 0s infinite linear}.pulse.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 1s infinite steps(8)}@keyframes svelte-1cj2gr0-spin{0%{transform:rotate(0deg)}100%{transform:rotate(360deg)}}.zephr-registration-form-checkbox.svelte-1gzpw2y{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-checkbox-label.svelte-1gzpw2y{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-checkmark.svelte-1gzpw2y{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid var(–zephr-color-text-main);border-radius:6px;margin-right:12px;cursor:pointer}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y{border-color:#009fe3}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y:after{content:””;position:absolute;width:6px;height:13px;border:solid #009fe3;border-width:0 2px 2px 0;transform:rotate(45deg);top:3px;left:8px;box-sizing:border-box}.zephr-registration-form-checkmark.disabled.svelte-1gzpw2y{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-checkmark.disabled.checked.svelte-1gzpw2y:after{border:solid var(–zephr-color-background-tinted);border-width:0 2px 2px 0}.zephr-registration-form-checkmark.error.svelte-1gzpw2y{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-radio.svelte-1qn5n0t{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-radio-label.svelte-1qn5n0t{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-radio-dot.svelte-1qn5n0t{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid #ebebeb;border-radius:50%;margin-right:12px}.checked.svelte-1qn5n0t{border-color:#009fe3}.checked.svelte-1qn5n0t:after{content:””;position:absolute;width:17px;height:17px;background:#009fe3;background:linear-gradient(#009fe3, #006cb5);border-radius:50%;top:2px;left:2px}.disabled.checked.svelte-1qn5n0t:after{background:var(–zephr-color-background-tinted)}.error.svelte-1qn5n0t{border:1px solid var(–zephr-color-warning-main)}.zephr-form-link.svelte-64wplc{margin:10px 0;color:#6ba5e9;text-decoration:underline;cursor:pointer;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-form-link-disabled.svelte-64wplc{color:var(–zephr-color-text-main);cursor:none;text-decoration:none}.zephr-registration-form-google-icon.svelte-1jnblvg{width:20px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}
.zephr-registration-form {
max-width: 100%;
background-image: url(/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg);
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
margin: 0px auto;
margin-bottom: 4rem;
padding: 20px;
}

.zephr-registration-form-text h6 {
font-size: 0.8rem;
}

.zephr-registration-form h4 {
font-size: 3rem;
}

.zephr-registration-form h4 {
font-size: 1.5rem;
}

.zephr-registration-form-button.svelte-17g75t9:hover {
background-color: #fc6a65;
border-color: #fc6a65;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9:disabled {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9 {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-text > * {
color: #FFFFFF;
font-weight: bold
font: 25px;
}
.zephr-registration-form-progress-bar.svelte-8qyhcl {
width: 100%;
border: 0;
border-radius: 20px;
margin-top: 10px;
display: none;
}
.zephr-registration-form-response-message-title.svelte-179421u {
font-weight: bold;
margin-bottom: 10px;
display: none;
}
.zephr-registration-form-response-message-success.svelte-179421u {
background-color: #8db869;
border: 1px solid #8db869;
color: white;
margin-top: -0.2rem;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(1){
font-size: 18px;
text-align: center;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(5){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(7){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(9){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj {
display: none;
color: white;
}
.zephr-registration-form-input.disabled.svelte-blfh8x, .zephr-registration-form-input.disabled.svelte-blfh8x:hover {
border: calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);
background-color: white;
}
.zephr-registration-form-checkbox-label.svelte-1gzpw2y {
display: flex;
align-items: center;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
font-size: 20px;
margin-bottom: -20px;
}

The newly identified reefs are in cold waters up to 420 meters below the surface, the Schmidt Ocean Institute, a nonprofit based in Palo Alto, Calif., that operates ocean research vessels, announced in a news release. Such a location probably helped corals living there remain pristine. Unlike corals that flourish in warm, shallow water with lots of sunlight to fuel symbiotic algae, deep-sea corals survive in darker parts of the ocean that don’t warm up as quickly under climate change (SN: 12/11/18).

It’s rare to find so much living coral in one spot, and scientists often need to get close to glimpse everything that’s hiding inside rocky reefs, Banks says. “Seeing these things for the first time is always a big ‘wow.’”

[embedded content]
Using a remotely operated vehicle, researchers captured the marvels of pristine coral reefs found hundreds of meters below the surface of the ocean. Shown are various creatures the team observed on deep-sea reefs in the Galápagos Islands Marine Reserve, including one dubbed Cacho De Coral. More

From 2018 to 2021, an estimated 10 billion snow crabs disappeared from the eastern Bering Sea off the coast of Alaska, with the population plummeting to record lows in 2021. Researchers had only speculated as to what happened to the missing crabs. Now, a study in the Oct. 20 Science finds that a marine heat wave probably spurred a mass die-off, in part by causing crabs to starve.

“It’s a fishery disaster in the truest sense of the word,” says Cody Szuwalski, a fishery biologist at the U.S. National Oceanic and Atmospheric Administration’s Alaska Fisheries Science Center in Seattle.

.email-conversion {
border: 1px solid #ffcccb;
color: white;
margin-top: 50px;
background-image: url(“/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg”);
padding: 20px;
clear: both;
}

.zephr-registration-form{max-width:440px;margin:20px auto;padding:20px;background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form *{box-sizing:border-box}.zephr-registration-form-text > *{color:var(–zephr-color-text-main)}.zephr-registration-form-relative-container{position:relative}.zephr-registration-form-flex-container{display:flex}.zephr-registration-form-input.svelte-blfh8x{display:block;width:100%;height:calc(var(–zephr-input-height) * 1px);padding-left:8px;font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input.svelte-blfh8x::placeholder{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-checkbox.svelte-blfh8x{width:auto;height:auto;margin:8px 5px 0 0;float:left}.zephr-registration-form-input-radio.svelte-blfh8x{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x{width:50px;padding:0;border-radius:50%}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch{border:none;border-radius:50%;padding:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch-wrapper{border:none;border-radius:50%;padding:0}.zephr-registration-form-input.disabled.svelte-blfh8x,.zephr-registration-form-input.disabled.svelte-blfh8x:hover{border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);background-color:var(–zephr-color-background-tinted)}.zephr-registration-form-input.error.svelte-blfh8x{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-label.svelte-1ok5fdj.svelte-1ok5fdj{margin-top:10px;display:block;line-height:30px;font-size:12px;color:var(–zephr-color-text-tinted);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj{display:block}.zephr-registration-form-button.svelte-17g75t9{height:calc(var(–zephr-button-height) * 1px);line-height:0;padding:0 20px;text-decoration:none;text-transform:capitalize;text-align:center;border-radius:calc(var(–zephr-button-borderRadius) * 1px);font-size:calc(var(–zephr-button-fontSize) * 1px);font-weight:normal;cursor:pointer;border-style:solid;border-width:calc(var(–zephr-button-borderWidth) * 1px);border-color:var(–zephr-color-action-tinted);transition:backdrop-filter 0.2s, background-color 0.2s;margin-top:20px;display:block;width:100%;background-color:var(–zephr-color-action-main);color:#fff;position:relative;overflow:hidden;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-button.svelte-17g75t9:hover{background-color:var(–zephr-color-action-tinted);border-color:var(–zephr-color-action-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled:hover{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-text.svelte-i1fi5{font-size:19px;text-align:center;margin:20px auto;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-divider-container.svelte-mk4m8o{display:flex;align-items:center;justify-content:center;margin:40px 0}.zephr-registration-form-divider-line.svelte-mk4m8o{height:1px;width:50%;margin:0 5px;background-color:var(–zephr-color-text-tinted);;}.zephr-registration-form-divider-text.svelte-mk4m8o{margin:0 12px;color:var(–zephr-color-text-main);font-size:14px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);white-space:nowrap}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message.svelte-179421u{text-align:center;padding:10px 30px;border-radius:5px;font-size:15px;margin-top:10px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message-title.svelte-179421u{font-weight:bold;margin-bottom:10px}.zephr-registration-form-response-message-success.svelte-179421u{background-color:#baecbb;border:1px solid #00bc05}.zephr-registration-form-response-message-error.svelte-179421u{background-color:#fcdbec;border:1px solid #d90c00}.zephr-registration-form-social-sign-in.svelte-gp4ky7{align-items:center}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7{height:55px;padding:0 15px;color:#000;background-color:#fff;box-shadow:0px 0px 5px rgba(0, 0, 0, 0.3);border-radius:10px;font-size:17px;display:flex;align-items:center;cursor:pointer;margin-top:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7:hover{background-color:#fafafa}.zephr-registration-form-social-sign-in-icon.svelte-gp4ky7{display:flex;justify-content:center;margin-right:30px;width:25px}.zephr-form-link-message.svelte-rt4jae{margin:10px 0 10px 20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-tcs.svelte-1wyy3bx{margin:20px 0 0 0;font-size:15px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-inline.svelte-1wyy3bx{margin:20px 0 0 0}.zephr-registration-form-progress-bar.svelte-8qyhcl{width:100%;border:0;border-radius:20px;margin-top:10px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-bar{background-color:var(–zephr-color-background-tinted);border:0;border-radius:20px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-value{background-color:var(–zephr-color-text-tinted);border:0;border-radius:20px}.zephr-registration-progress-bar-step.svelte-8qyhcl{margin:auto;color:var(–zephr-color-text-tinted);font-size:12px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-progress-bar-step.svelte-8qyhcl:first-child{margin-left:0}.zephr-registration-progress-bar-step.svelte-8qyhcl:last-child{margin-right:0}.zephr-registration-form-input-error-text.svelte-19a73pq{color:var(–zephr-color-warning-main);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-select.svelte-19a73pq{display:block;appearance:auto;width:100%;height:calc(var(–zephr-input-height) * 1px);font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-color-text-main);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;padding:10px}.zephr-registration-form-input-select.disabled.svelte-19a73pq{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.unselected.svelte-19a73pq{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.error.svelte-19a73pq{border-color:var(–zephr-color-warning-main)}.zephr-registration-form-input-textarea.svelte-19a73pq{background-color:#fff;border:1px solid #ddd;color:#222;font-size:14px;font-weight:300;padding:16px;width:100%}.zephr-registration-form-input-slider-output.svelte-19a73pq{margin:13px 0 0 10px}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.spin.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 2s 0s infinite linear}.pulse.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 1s infinite steps(8)}@keyframes svelte-1cj2gr0-spin{0%{transform:rotate(0deg)}100%{transform:rotate(360deg)}}.zephr-registration-form-checkbox.svelte-1gzpw2y{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-checkbox-label.svelte-1gzpw2y{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-checkmark.svelte-1gzpw2y{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid var(–zephr-color-text-main);border-radius:6px;margin-right:12px;cursor:pointer}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y{border-color:#009fe3}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y:after{content:””;position:absolute;width:6px;height:13px;border:solid #009fe3;border-width:0 2px 2px 0;transform:rotate(45deg);top:3px;left:8px;box-sizing:border-box}.zephr-registration-form-checkmark.disabled.svelte-1gzpw2y{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-checkmark.disabled.checked.svelte-1gzpw2y:after{border:solid var(–zephr-color-background-tinted);border-width:0 2px 2px 0}.zephr-registration-form-checkmark.error.svelte-1gzpw2y{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-radio.svelte-1qn5n0t{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-radio-label.svelte-1qn5n0t{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-radio-dot.svelte-1qn5n0t{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid #ebebeb;border-radius:50%;margin-right:12px}.checked.svelte-1qn5n0t{border-color:#009fe3}.checked.svelte-1qn5n0t:after{content:””;position:absolute;width:17px;height:17px;background:#009fe3;background:linear-gradient(#009fe3, #006cb5);border-radius:50%;top:2px;left:2px}.disabled.checked.svelte-1qn5n0t:after{background:var(–zephr-color-background-tinted)}.error.svelte-1qn5n0t{border:1px solid var(–zephr-color-warning-main)}.zephr-form-link.svelte-64wplc{margin:10px 0;color:#6ba5e9;text-decoration:underline;cursor:pointer;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-form-link-disabled.svelte-64wplc{color:var(–zephr-color-text-main);cursor:none;text-decoration:none}.zephr-registration-form-google-icon.svelte-1jnblvg{width:20px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}
.zephr-registration-form {
max-width: 100%;
background-image: url(/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg);
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
margin: 0px auto;
margin-bottom: 4rem;
padding: 20px;
}

.zephr-registration-form-text h6 {
font-size: 0.8rem;
}

.zephr-registration-form h4 {
font-size: 3rem;
}

.zephr-registration-form h4 {
font-size: 1.5rem;
}

.zephr-registration-form-button.svelte-17g75t9:hover {
background-color: #fc6a65;
border-color: #fc6a65;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9:disabled {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9 {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-text > * {
color: #FFFFFF;
font-weight: bold
font: 25px;
}
.zephr-registration-form-progress-bar.svelte-8qyhcl {
width: 100%;
border: 0;
border-radius: 20px;
margin-top: 10px;
display: none;
}
.zephr-registration-form-response-message-title.svelte-179421u {
font-weight: bold;
margin-bottom: 10px;
display: none;
}
.zephr-registration-form-response-message-success.svelte-179421u {
background-color: #8db869;
border: 1px solid #8db869;
color: white;
margin-top: -0.2rem;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(1){
font-size: 18px;
text-align: center;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(5){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(7){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(9){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj {
display: none;
color: white;
}
.zephr-registration-form-input.disabled.svelte-blfh8x, .zephr-registration-form-input.disabled.svelte-blfh8x:hover {
border: calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);
background-color: white;
}
.zephr-registration-form-checkbox-label.svelte-1gzpw2y {
display: flex;
align-items: center;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
font-size: 20px;
margin-bottom: -20px;
}

On average, snow crabs bring in about $150 million of annual revenue for Alaskan fisheries. In the 2021-2022 crabbing season, that revenue fell to around $24 million. With marine heat waves becoming more common because of human-caused climate change, the future of such fisheries and arctic marine ecosystems, more broadly, is uncertain, researchers say (SN: 7/13/23).

The new research can help fishery managers anticipate and prepare for similar events such as the crab collapse in the future, Szuwalski says, particularly when it comes to getting proper disaster aid to affected fishers quickly.

Usually, cold, arctic water makes ideal habitat for snow crabs (Chionoecetes opilio) and other crustaceans. As winter’s thick sea ice melts, the frigid meltwater settles on the seafloor, creating a cold-water pool with temperatures below 2˚ Celsius. Crabs thrive in this chilly sanctuary on the eastern Bering Sea shelf. But a marine heat wave in the region in 2018 and 2019 prevented the usual amount of sea ice from forming, and, according to yearly temperature and population survey data, the cold pool never appeared and then the crab population collapsed.

Szuwalski and colleagues used computer models to analyze temperature data combined with population surveys, fishing catch numbers and lab experiments to look for drivers behind the sudden collapse. Two causes stood out: higher water temperatures and an initially dense crab population.

The water temperature probably didn’t kill the crabs directly, as snow crabs in laboratories can survive in waters up to 12° C. Instead, the crabs might have starved to death, Szuwalski says.

Data show the crab population initially boomed in 2018 — reaching historic highs — thanks to ideal ocean conditions for newborn crabs around 2010. But the crabs also occupied a smaller area than normal, though Szuwalski and colleagues are uncertain why. That means more crabs were crammed onto less space on the shelf. Then came the heat wave. Higher water temperatures can rev the cold-blooded crabs’ metabolism; previous research has shown that the calorie requirements of snow crabs in labs almost double as water temperature rises from 0° to 3° C. 

As a result, the crowded crabs probably needed more food, but because of the smaller foraging area they had even fewer resources to sink their claws into. Compared with similar-sized crabs from the previous year, those surveyed in 2018 had lower body weights, another clue starvation played a role in the missing crabs.

“It’s just yet another example of something we didn’t expect, but now we have to live with,” says Christopher Harley, a marine ecologist at the University of British Columbia in Vancouver, who was not involved with the research. In the eastern Bering Sea, it could take at least four years before more crabs of a fishable size start showing up, meaning fishers there will remain in a lurch.

Such effects of marine heat waves are likely to extend beyond snow crabs. Ecosystems in northern latitudes, such as Alaska’s, are changing more rapidly in response to climate change than anywhere else (SN: 8/11/22). Scientists can typically use data from the past to help predict and prepare for changes in the future. But the future increasingly holds events that have never happened on record before — like the snow crab population collapse — so they’re harder to prepare for, Harley says.

That’s especially true, he says, because there hasn’t been enough attention on the secondary effects of marine heat waves on cold-blooded creatures, such as higher calorie needs and the risk of starvation. More

How microbes survive in lakes far beneath Antarctica’s ice sheet has been a mystery. Now scientists have figured out what’s on the menu for microbes in one buried lake in West Antarctica.

The lake’s bacteria and other microbial inhabitants get by on carbon that seawater left behind thousands of years ago, researchers report in the April AGU Advances. The find adds to existing evidence that, during a period of warming about 6,000 years ago, the ice sheet in West Antarctica was smaller than it is today. That allowed seawater to deposit nutrients in what is now a lake bed buried under hundreds of meters of ice.

.email-conversion {
border: 1px solid #ffcccb;
color: white;
margin-top: 50px;
background-image: url(“/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg”);
padding: 20px;
clear: both;
}

.zephr-registration-form{max-width:440px;margin:20px auto;padding:20px;background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form *{box-sizing:border-box}.zephr-registration-form-text > *{color:var(–zephr-color-text-main)}.zephr-registration-form-relative-container{position:relative}.zephr-registration-form-flex-container{display:flex}.zephr-registration-form-input.svelte-blfh8x{display:block;width:100%;height:calc(var(–zephr-input-height) * 1px);padding-left:8px;font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input.svelte-blfh8x::placeholder{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-checkbox.svelte-blfh8x{width:auto;height:auto;margin:8px 5px 0 0;float:left}.zephr-registration-form-input-radio.svelte-blfh8x{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x{width:50px;padding:0;border-radius:50%}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch{border:none;border-radius:50%;padding:0}.zephr-registration-form-input-color[type=”color”].svelte-blfh8x::-webkit-color-swatch-wrapper{border:none;border-radius:50%;padding:0}.zephr-registration-form-input.disabled.svelte-blfh8x,.zephr-registration-form-input.disabled.svelte-blfh8x:hover{border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);background-color:var(–zephr-color-background-tinted)}.zephr-registration-form-input.error.svelte-blfh8x{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-input-label.svelte-1ok5fdj.svelte-1ok5fdj{margin-top:10px;display:block;line-height:30px;font-size:12px;color:var(–zephr-color-text-tinted);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj{display:block}.zephr-registration-form-button.svelte-17g75t9{height:calc(var(–zephr-button-height) * 1px);line-height:0;padding:0 20px;text-decoration:none;text-transform:capitalize;text-align:center;border-radius:calc(var(–zephr-button-borderRadius) * 1px);font-size:calc(var(–zephr-button-fontSize) * 1px);font-weight:normal;cursor:pointer;border-style:solid;border-width:calc(var(–zephr-button-borderWidth) * 1px);border-color:var(–zephr-color-action-tinted);transition:backdrop-filter 0.2s, background-color 0.2s;margin-top:20px;display:block;width:100%;background-color:var(–zephr-color-action-main);color:#fff;position:relative;overflow:hidden;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-button.svelte-17g75t9:hover{background-color:var(–zephr-color-action-tinted);border-color:var(–zephr-color-action-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-button.svelte-17g75t9:disabled:hover{background-color:var(–zephr-color-background-tinted);border-color:var(–zephr-color-background-tinted)}.zephr-registration-form-text.svelte-i1fi5{font-size:19px;text-align:center;margin:20px auto;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-divider-container.svelte-mk4m8o{display:flex;align-items:center;justify-content:center;margin:40px 0}.zephr-registration-form-divider-line.svelte-mk4m8o{height:1px;width:50%;margin:0 5px;background-color:var(–zephr-color-text-tinted);;}.zephr-registration-form-divider-text.svelte-mk4m8o{margin:0 12px;color:var(–zephr-color-text-main);font-size:14px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);white-space:nowrap}.zephr-registration-form-response-message.svelte-179421u{text-align:center;padding:10px 30px;border-radius:5px;font-size:15px;margin-top:10px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-response-message-title.svelte-179421u{font-weight:bold;margin-bottom:10px}.zephr-registration-form-response-message-success.svelte-179421u{background-color:#baecbb;border:1px solid #00bc05}.zephr-registration-form-response-message-error.svelte-179421u{background-color:#fcdbec;border:1px solid #d90c00}.zephr-recaptcha-tcs.svelte-1wyy3bx{margin:20px 0 0 0;font-size:15px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-recaptcha-inline.svelte-1wyy3bx{margin:20px 0 0 0}.zephr-registration-form-social-sign-in.svelte-gp4ky7{align-items:center}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7{height:55px;padding:0 15px;color:#000;background-color:#fff;box-shadow:0px 0px 5px rgba(0, 0, 0, 0.3);border-radius:10px;font-size:17px;display:flex;align-items:center;cursor:pointer;margin-top:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-social-sign-in-button.svelte-gp4ky7:hover{background-color:#fafafa}.zephr-registration-form-social-sign-in-icon.svelte-gp4ky7{display:flex;justify-content:center;margin-right:30px;width:25px}.zephr-form-link-message.svelte-rt4jae{margin:10px 0 10px 20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-progress-bar.svelte-8qyhcl{width:100%;border:0;border-radius:20px;margin-top:10px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-bar{background-color:var(–zephr-color-background-tinted);border:0;border-radius:20px}.zephr-registration-form-progress-bar.svelte-8qyhcl::-webkit-progress-value{background-color:var(–zephr-color-text-tinted);border:0;border-radius:20px}.zephr-registration-progress-bar-step.svelte-8qyhcl{margin:auto;color:var(–zephr-color-text-tinted);font-size:12px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-progress-bar-step.svelte-8qyhcl:first-child{margin-left:0}.zephr-registration-progress-bar-step.svelte-8qyhcl:last-child{margin-right:0}.zephr-registration-form-input-inner-text.svelte-lvlpcn{cursor:pointer;position:absolute;top:50%;transform:translateY(-50%);right:10px;color:var(–zephr-color-text-main);font-size:12px;font-weight:bold;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-error-text.svelte-19a73pq{color:var(–zephr-color-warning-main);font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-input-select.svelte-19a73pq{display:block;appearance:auto;width:100%;height:calc(var(–zephr-input-height) * 1px);font-size:16px;border:calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-color-text-main);border-radius:calc(var(–zephr-input-borderRadius) * 1px);transition:border-color 0.25s ease, box-shadow 0.25s ease;outline:0;color:var(–zephr-color-text-main);background-color:#fff;padding:10px}.zephr-registration-form-input-select.disabled.svelte-19a73pq{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.unselected.svelte-19a73pq{color:var(–zephr-color-background-tinted)}.zephr-registration-form-input-select.error.svelte-19a73pq{border-color:var(–zephr-color-warning-main)}.zephr-registration-form-input-textarea.svelte-19a73pq{background-color:#fff;border:1px solid #ddd;color:#222;font-size:14px;font-weight:300;padding:16px;width:100%}.zephr-registration-form-input-slider-output.svelte-19a73pq{margin:13px 0 0 10px}.spin.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 2s 0s infinite linear}.pulse.svelte-1cj2gr0{animation:svelte-1cj2gr0-spin 1s infinite steps(8)}@keyframes svelte-1cj2gr0-spin{0%{transform:rotate(0deg)}100%{transform:rotate(360deg)}}.zephr-registration-form-input-radio.svelte-1qn5n0t{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-radio-label.svelte-1qn5n0t{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-radio-dot.svelte-1qn5n0t{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid #ebebeb;border-radius:50%;margin-right:12px}.checked.svelte-1qn5n0t{border-color:#009fe3}.checked.svelte-1qn5n0t:after{content:””;position:absolute;width:17px;height:17px;background:#009fe3;background:linear-gradient(#009fe3, #006cb5);border-radius:50%;top:2px;left:2px}.disabled.checked.svelte-1qn5n0t:after{background:var(–zephr-color-background-tinted)}.error.svelte-1qn5n0t{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-checkbox.svelte-1gzpw2y{position:absolute;opacity:0;cursor:pointer;height:0;width:0}.zephr-registration-form-checkbox-label.svelte-1gzpw2y{display:flex;align-items:center;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-checkmark.svelte-1gzpw2y{position:relative;box-sizing:border-box;height:23px;width:23px;background-color:#fff;border:1px solid var(–zephr-color-text-main);border-radius:6px;margin-right:12px;cursor:pointer}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y{border-color:#009fe3}.zephr-registration-form-checkmark.checked.svelte-1gzpw2y:after{content:””;position:absolute;width:6px;height:13px;border:solid #009fe3;border-width:0 2px 2px 0;transform:rotate(45deg);top:3px;left:8px;box-sizing:border-box}.zephr-registration-form-checkmark.disabled.svelte-1gzpw2y{border:1px solid var(–zephr-color-background-tinted)}.zephr-registration-form-checkmark.disabled.checked.svelte-1gzpw2y:after{border:solid var(–zephr-color-background-tinted);border-width:0 2px 2px 0}.zephr-registration-form-checkmark.error.svelte-1gzpw2y{border:1px solid var(–zephr-color-warning-main)}.zephr-registration-form-google-icon.svelte-1jnblvg{width:20px}.zephr-form-link.svelte-64wplc{margin:10px 0;color:#6ba5e9;text-decoration:underline;cursor:pointer;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-form-link-disabled.svelte-64wplc{color:var(–zephr-color-text-main);cursor:none;text-decoration:none}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}.zephr-registration-form-password-progress.svelte-d1zv9r{display:flex;margin-top:10px}.zephr-registration-form-password-bar.svelte-d1zv9r{width:100%;height:4px;border-radius:2px}.zephr-registration-form-password-bar.svelte-d1zv9r:not(:first-child){margin-left:8px}.zephr-registration-form-password-requirements.svelte-d1zv9r{margin:20px 0;justify-content:center}.zephr-registration-form-password-requirement.svelte-d1zv9r{display:flex;align-items:center;color:var(–zephr-color-text-tinted);font-size:12px;height:20px;font-family:var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont)}.zephr-registration-form-password-requirement-icon.svelte-d1zv9r{margin-right:10px;font-size:15px}
.zephr-registration-form {
max-width: 100%;
background-image: url(/wp-content/themes/sciencenews/client/src/images/cta-module@2x.jpg);
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
margin: 0px auto;
margin-bottom: 4rem;
padding: 20px;
}

.zephr-registration-form-text h6 {
font-size: 0.8rem;
}

.zephr-registration-form h4 {
font-size: 3rem;
}

.zephr-registration-form h4 {
font-size: 1.5rem;
}

.zephr-registration-form-button.svelte-17g75t9:hover {
background-color: #fc6a65;
border-color: #fc6a65;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9:disabled {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-button.svelte-17g75t9 {
background-color: #e04821;
border-color: #e04821;
width: 150px;
margin-left: auto;
margin-right: auto;
}
.zephr-registration-form-text > * {
color: #FFFFFF;
font-weight: bold
font: 25px;
}
.zephr-registration-form-progress-bar.svelte-8qyhcl {
width: 100%;
border: 0;
border-radius: 20px;
margin-top: 10px;
display: none;
}
.zephr-registration-form-response-message-title.svelte-179421u {
font-weight: bold;
margin-bottom: 10px;
display: none;
}
.zephr-registration-form-response-message-success.svelte-179421u {
background-color: #8db869;
border: 1px solid #8db869;
color: white;
margin-top: -0.2rem;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(1){
font-size: 18px;
text-align: center;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(5){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(7){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-text.svelte-i1fi5:nth-child(9){
font-size: 18px;
text-align: left;
margin: 20px auto;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
}
.zephr-registration-form-input-label.svelte-1ok5fdj span.svelte-1ok5fdj {
display: none;
color: white;
}
.zephr-registration-form-input.disabled.svelte-blfh8x, .zephr-registration-form-input.disabled.svelte-blfh8x:hover {
border: calc(var(–zephr-input-borderWidth) * 1px) solid var(–zephr-input-borderColor);
background-color: white;
}
.zephr-registration-form-checkbox-label.svelte-1gzpw2y {
display: flex;
align-items: center;
font-family: var(–zephr-typography-body-font), var(–zephr-typography-body-fallbackFont);
color: white;
font-size: 20px;
margin-bottom: -20px;
}

This study is among the first to provide evidence from beneath the ice that the ice sheet was smaller in the not-so-distant past, geologically speaking, before growing back to its modern size, says Greg Balco, a geochemist at the Berkeley Geochronology Center in California.

Understanding how the ice sheet changed during past periods of warming is crucial to predicting Antarctica’s future as the world continues to warm due to human-caused climate change, says Balco, who was not involved in the new study.

Hundreds of lakes pool under Antarctica’s massive ice sheet, the result of the underside of the ice ever-so-slowly melting due to heat from the Earth’s interior. The lakes tend to be pitch-black, near freezing and are almost all isolated from the outside world.

These less-than-ideal conditions should make them hostile to life. “If I were a microbe, I wouldn’t want to live in the cold, dark depths where I haven’t seen the sun or a new nutrient in thousands of years,” says Ryan Venturelli, a paleoglaciologist at the Colorado School of Mines in Golden. Yet billions of microbes — and even some animals — have found a way to thrive in these subglacial waterbodies (SN: 4/21/23).

As the last glacial period came to a close, starting around 15,000 years ago, ice sheets around the world retreated. Computer simulations have predicted that as the climate warmed, the ice sheet in West Antarctica may have shrunk to an even smaller size than it is today. But working out what a smaller ice sheet might have looked like isn’t easy since most of the evidence for it is now locked under ice, Balco says.

In 2018, Venturelli joined a team of about 30 scientists headed to a remote corner of West Antarctica to drill for the past. The journey took them to Lake Mercer: a body of subglacial water that today sits 150 kilometers from the sea.

It took the expedition over a week of using a hot-water drill 24 hours a day to pierce through just over a kilometer of ice to reach the lake. “There was a lot of cheering and high-fiving” when the drill finally made it through, Venturelli recalls. Lake Mercer is only the second subglacial lake in the world that scientists have ever managed to reach.

Paleoglaciologist Ryan Venturelli holds a tube of sediment collected from the bed of Lake Mercer. Carbon in this sediment core reveals that the lake was connected to the ocean 6,000 years ago.Billy Collins

The team collected and analyzed lake water and sediment samples from the lake bed. This work revealed traces of 6,000-year-old carbon-14, a form of the element that’s made in the atmosphere and then falls to Earth. For that carbon to get past the ice, the lake would have had to have contact with the outside world. 

The researchers didn’t spot any telltale signs of ancient photosynthesizing plankton, suggesting that the area wasn’t open ocean when the carbon settled in the sediment. Instead, seawater carrying the carbon must have come to the lake. That means that ocean water had to have flowed under the ice about 250 kilometers farther inland than it does today, the researchers say. 

“There’s no other way to get carbon-14 in there,” Balco says. “You can’t push it through ice. Organisms can’t tunnel through. The only way for it to get it there is for ocean water to get under the ice sheet.”

Seawater does flow under the ice today — but not as far inland as the lake’s location. So the edge of the ice shelf was probably closer to Lake Mercer several thousand years ago. That suggests, the team says, that the ice sheet over West Antarctica was probably smaller back then.

Microorganisms living in this area 6,000 years ago would have feasted on the inflow from the ocean. And their descendants still seem to as well. The researchers found traces of carbon-14 in the water samples as well as in the sediment, suggesting the microbes are recycling the ancient carbon deposited in the lake bed as food.

The new study emphasizes how much information is waiting to be found in Antarctica’s hidden lakes, Venturelli says. “There are about 675 lakes under the ice sheet, and we’ve only sampled two,” she says. “I would very much like to drill into every single one of them.” More

In shallow coastal waters of the Indian and Pacific oceans, a seagrass-scrounging cousin of the manatee is in trouble. Environmental strains like pollution and habitat loss pose a major threat to dugong (Dugong dugon) survival, so much so that in December, the International Union for Conservation of Nature upgraded the species’ extinction risk status to vulnerable. Some populations are now classified as endangered or critically endangered.

If that weren’t bad enough, the sea cows are at risk of losing the protection of a group who has long looked after them: the Torres Strait Islanders. These Indigenous people off the coast of Australia historically have been stewards of the dugong populations there, sustainably hunting the animals and monitoring their numbers. But the Torres Strait Islanders are also threatened, in part because sea levels are rising and encroaching on their communities, and warmer air and sea temperatures are making it difficult for people to live in the region.

Science News headlines, in your inbox

Headlines and summaries of the latest Science News articles, delivered to your email inbox every Thursday.

Thank you for signing up!

There was a problem signing you up.

This situation isn’t unique to dugongs. A global analysis of 385 culturally important plant and animal species found that 68 percent were both biologically vulnerable and at risk of losing their cultural protections, researchers report January 3 in the Proceedings of the National Academy of Sciences.

The findings clearly illustrate that biology shouldn’t be the primary factor in shaping conservation policy, says cultural anthropologist Victoria Reyes-García. When a culture dwindles, the species that are important to that culture are also under threat. To be effective, more conservation efforts need to consider the vulnerability of both the species and the people that have historically cared for them, she says.

“A lot of the people in the conservation arena think we need to separate people from nature,” says Reyes-García, of the Catalan Institution for Research and Advanced Studies and the Autonomous University of Barcelona. But that tactic overlooks the caring relationship many cultural groups – like the Torres Strait Islanders – have with nature, she says.

“Indigenous people, local communities, also other ethnic groups – they are good stewards of their biodiversity,” says Ina Vandebroek, an ethnobotanist at the University of the West Indies at Mona in Kingston, Jamaica, who was not involved in the work. “They have knowledge, deep knowledge, about their environments that we really cannot overlook.”

One way to help shift conservation efforts is to give species a “biocultural status,” which would provide a fuller picture of their vulnerability, Reyes-García and colleagues say. In the study, the team used existing language vitality research to determine a culture’s risk of disappearing: The more a cultural group’s language use declines, the more that culture is threatened. And the more a culture is threatened, the more culturally vulnerable its important species are. Researchers then combined a species’ cultural and biological vulnerability to arrive at its biocultural status. In the dugong’s case, its biocultural status is endangered, meaning it is more at risk than its IUCN categorization suggests.

This intersectional approach to conservation can help species by involving the people that have historically cared for them (SN: 3/2/22). It can also highlight when communities need support to continue their stewardship, Reyes-García says. She hopes this new framework will spark more conservation efforts that recognize local communities’ rights and encourage their participation – leaning into humans’ connection with nature instead of creating more separation (SN: 3/8/22).       More

The next time you spot a sea sponge, say “gesundheit!” Some sponges regularly “sneeze” to clear debris from their porous bodies.

As filter feeders, sponges draw in water through inlet pores — called ostia — and strain it through an internal canal system for nutrients. But there are also inedible bits in the water, like sediment. To prevent the undesirable junk from clogging up their outer pores, a Caribbean tube sponge (Aplysina archeri) uses mucus to trap and sneeze out unwanted particles, Niklas Kornder, a marine biologist at the University of Amsterdam, and colleagues report online August 10 in Current Biology. To the team’s surprise, it found that the sponge expels its snot from the same pores through which it absorbs water.

Sign Up For the Latest from Science News

Headlines and summaries of the latest Science News articles, delivered to your inbox

Thank you for signing up!

There was a problem signing you up.

It’s “like someone with a runny nose,” says team member Sally Leys, an evolutionary biologist at the University of Alberta in Edmonton, Canada. “It’s constantly streaming, but it’s going counterflow to the in-current.”

Researchers knew that sponges used contractions dubbed “sneezing” to move water through their bodies in a one-way flow. Typically, water comes in through numerous ostia and leaves through the osculum, a hole near the sponges’ top.

But when the team captured time-lapse video of A. archeri, it saw tiny specks of mucus exiting from the ostia, moving against the flow of incoming water. Sneezelike contractions appeared to expel and move the specks along a “mucus highway” across the surface of the sponge to points where they collected in stringy, gooey clumps. Unlike an explosive human sneeze, the sponges slowly and continuously secreted debris-laden mucus from their ostia, with one contraction taking between 20 and 50 minutes, the study finds.

[embedded content]
The Caribbean tube sponge (Aplysina archeri) uses contractions — called “sneezes” — to help eject mucus from its pores, or ostia. As the time-lapse video zooms in closer, it’s possible to see tiny specks of debris floating out of these pores and traveling along a “mucus highway” where they collect into stringy clumps of goo floating above the surface of the sponge. In real time, this sponge takes between 20 and 50 minutes to complete a sneeze.

Other sea critters feast on these ocean boogers, like brittle stars and small crustaceans. Scientists view sponges primarily as habitat builders, but the mucus buffet shows they also perform an important function as food providers, says Amanda Kahn, a marine biologist at Moss Landing Marine Labs in California who was not involved with this work.

“There’s so much to be said for a study that really spends time and watches,” Kahn says. “They let the animals show for themselves what was happening.”

Most sponges appear to sneeze, so it’s likely not just A. archeri that uses the counterflow technique, Leys says. The team also noted a similar behavior in an Indo-Pacific sponge (Chelonaplysilla sp). But biologists need to dig deeper to figure out how widespread the mechanism is. It’s also unclear exactly what the mucus is or how it’s moving backward through pores. More

Cooler, higher locales may not be very welcoming to some hummingbirds trying to escape rising temperatures and other effects of climate change.

Anna’s hummingbirds live no higher than about 2,600 meters above sea level. If the birds attempt to expand their range to include higher altitudes, they may struggle to fly well in the thinner air, researchers report May 26 in the Journal of Experimental Biology.

These hummingbirds have expanded their range in the past. Once only found in Southern California, the birds now live as far north as Vancouver, says Austin Spence, an ecologist at the University of California, Davis. That expansion is probably due to climate change and people using feeders to attract hummingbirds, he says.

Sign Up For the Latest from Science News

Headlines and summaries of the latest Science News articles, delivered to your inbox

Thank you for signing up!

There was a problem signing you up.

Spence and colleagues collected 26 Anna’s hummingbirds (Calypte anna) from different elevations in the birds’ natural range in California. The team transported the birds to an aviary about 1,200 meters above sea level and measured their metabolic rate when hovering. After relocating the hummingbirds to a field station at 3,800 meters altitude, the researchers let the birds rest for at least 12 hours and then measured that rate again.

The rate was 37 percent lower, on average, at the higher elevation than the aviary, even though the birds should have been working harder to stay aloft in the thinner air (SN: 2/8/18). At higher altitudes, hovering, which takes a lot of energy compared with other forms of flight, is more challenging and requires even more energy, Spence says. The decrease in metabolic rate shows that the birds’ hovering performance was suffering, he says. “Low oxygen and low air pressure may be holding them back as they try to move upslope.”

Additional work is needed to see whether the birds might be able to better adjust if given weeks or months to acclimate to the conditions at gradually higher altitudes. More