Humans

From hydras to humans, this short book by two marine biologists explores the peculiar process of regeneration, showing that it is a far bigger subject than it might at first seem

Humans

30 March 2022

By Simon Ings

Is the regeneration of a forest after fire fundamentally the same as an animal regrowing a body part?KarenHBlack/Getty Images
What Is Regeneration?
Jane Maienschein and Kate MacCord
University of Chicago Press (out 6 April)Advertisement

SOME animals are able to grow an entire new body from tiny parts. Crabs and lobsters can regenerate lost tentacles and claws. Hydras and some worms can regrow their heads. We humans can replace our skin, hair, fingernails and even our liver.
Regeneration is such a peculiar ability that, even in science, it is surprisingly under-researched. As a result, there is much we still don’t know. What Is Regeneration? is a collaborative effort between Jane Maienschein and Kate MacCord, both at the Marine Biological Laboratory in Woods Hole, Massachusetts, to fill some of the gaps. Together, they explore why regeneration occurs when it does, why it doesn’t always happen and what the process can tell us about the grander mysteries of birth, death and development.
It turns out to be a seemingly simple phenomena that, on closer inspection, becomes far more complicated. For instance, are we thinking only about regeneration of structure, about regeneration of function or both? Is the regeneration of the gut flora in your intestines after a course of antibiotics or the regeneration of woodland after a forest fire at all similar to regrowing a body part?
To try to pin it down, the authors begin with a history of the study of the subject, starting with Aristotle and ending with Magdalena Zernicka-Goetz’s ongoing research on cellular signalling. Their account pivots on the work of Thomas Hunt Morgan (better known as a pioneer of chromosomal genetics) and, in particular, his 1901 book Regeneration. Morgan, more than anyone before or since, attempted to establish clear boundaries around the phenomenon, and the terminology he came up with remains useful.
He identified three kinds of regeneration. The first two are restorative regeneration, which occurs in response to injury, and physiological regeneration, which describes replacement, as when an elk moults its antlers and new ones grow in their place. The third, morphallaxis, refers to more extreme cases, such as when a hydra, cut into pieces, reorganises itself into a new hydra without going through the normal processes of cell division.
The key to this categorisation is that the mechanisms of regeneration aren’t, as the authors put it, “a special response to changing environmental conditions but, rather, an internal normal process of growth and development”.
So here is the problem: if the mechanisms of regeneration can’t be distinguished from those of growth and development, what is to stop everything ceaselessly regenerating? What dictates the process of regrowth and why does it happen only in some tissues, in some species and only some of the time?
Maienschein and MacCord argue that, to fully understand this, we need to see regeneration as a window into the world of biology in general, and the complex feedback loops that decide what grows, divides and dies, where and when.
Far from being an interesting curio, then, studying regeneration can tell us much about life in general, from a cellular level right up to the level of ecosystems, and inform everything from regenerative therapies using stem cells to ecosystem protection and recovery.
Seen through this lens, regeneration is a far bigger subject than it might at first seem, and Maienschein and MacCord take fewer than 200 pages to anatomise the complexities and ambiguities that their simple question throws up. It is to their credit that they mostly focus on the big picture and don’t make the biology any more complex than it needs to be.

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By Katie Smith-Wong

Looking for one whale in the vast, deep ocean was never going to be easyCourtesy of Bleecker Street
The Loneliest Whale: The Search for 52
Joshua Zeman
Digital download from 4 AprilAdvertisement

IN 1989, the Woods Hole Oceanographic Institution in Massachusetts detected an unknown sonic presence at 52 hertz. It was initially thought to be from a submarine, but marine biologist William Watkins later determined that it was the sonar signature of a whale, which he gave the nickname “52”.
It is an unusually high frequency for whale vocalisations, and Watkins was intrigued enough to search for 52 until his death in 2004. But despite picking up 52’s call every year, Watkins never found the mysterious whale.
In The Loneliest Whale: The Search for 52, US film-maker Joshua Zeman picks up the search where Watkins left off, and sets out to find a whale that has since taken on almost mythical proportions.
Why 52 calls at this frequency is also a mystery – the whale’s species hasn’t been confirmed, and it is possible that it is the only one of its kind in the ocean. The one thing we do know is that 52 is almost certainly a he: male whales do the singing.
The reason for 52’s presumed loneliness has nothing to do with the fact that he has always been detected swimming alone. Instead, it is because the unique frequency of his call means that other whales can’t understand to respond. With 52’s unique call as the only lead, Zeman launches a seven-day search mission with bioacoustics specialist John Hildebrand and research biologist John Calambokidis.
They begin in the waters off California, at the Port of Los Angeles – the busiest container port in the western hemisphere. Their initial hopes aren’t high: the Pacific Ocean is deep and wide and the chances of finding 52 seem roughly the same as those of 52 finding a mate.
Zeman’s documentary has a strong sense of exploration and ambition: he believes he can locate 52, who has become the Moby Dick to Zeman’s Ahab. Although there is an underlying sense of excitement as to whether 52 can finally be found, there is a human aspect to the search and a personal story behind Zeman’s fascination.
In our increasingly connected world where contact and interaction is only the click of a button away, the fact that so many people still report feeling lonely makes it easy to identify with 52’s situation. There is something deeply affecting about a creature as intelligent and social as we know whales to be, swimming the vast ocean, year after year, never having any proper contact with another of its kind.
This, combined with a growing awareness of the harm that human activity has caused whales, has made 52 something of a focal point for whale conservation, with articles, poems and even a song by the K-pop band BTS about his plight.
Yet this is a story that goes deeper than just one whale. Whale populations are still under threat from hunting, pollution, climate change and collisions with ships. Even if they avoid these perils, the noise of shipping can drown out a whale’s calls, regardless of the frequency it may use. Arguably, Zeman’s quest says more about our collective guilt about this state of affairs than it does about our desire to solve the scientific mysteries surrounding 52.
Finding him is never a foregone conclusion. In fact, as 52 has never been seen or even definitively proven to exist, some within the scientific community are sceptical there is even a 52 to find.
Zeman’s attempt to create a sense of thrill and adventure as he embarks on his quest is hit-and-miss. Exciting footage of the search is punctuated with evocative images of the oceans, which makes the documentary’s tone feel inconsistent. At times, there isn’t enough to elevate the film above being a group of people spending time in a boat. At least not until the closing moments, when it appears that the team’s efforts may not have been in vain.
Overall, The Loneliest Whale: The Search for 52 offers a moving insight into a legendary whale and Zeman’s curiosity is infectious. Frustratingly, though, there isn’t enough discussion and explanation of the science behind whale communication, which leaves viewers, much like Zeman, wondering if they might have missed something important along the way.

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Martin Meissner/AP/Shutterstock
“THE time to repair the roof is when the sun is shining,” US president John F. Kennedy once said. It is an adage that Europe must now wrestle with.
With spring blossoming even as war continues to darken the continent, it is hard to spend too much time thinking about next winter. Yet the geopolitical uncertainty created by Russia’s invasion of Ukraine means volatile energy prices are guaranteed this year. UK energy bill projections for October have yo-yoed with oil and gas prices in recent weeks, from a high of £3000 a year on average to a still-very-high low of … More

The DNA of people who lived in Great Britain thousands of years ago has markers of natural selection at work – and the driving force seems to have been a shortage of vitamin D

Humans

29 March 2022

By Michael Marshall
An artist’s impression of a Bronze age settlementLennart Larsen/Nationalmuseet
Natural selection was at work on Bronze Age Britons, ancient DNA reveals. Within the past 4500 years, evolution has acted on genes involved in the production of vitamin D – which people living in Britain are sometimes short of due to a lack of sunlight for much of the year.
The genetic changes have had knock-on effects on other traits, from the ability of people todigest milk to their skin colour.
One of the ways evolutionary change can happen is through natural selection: … More

Stress-linked changes in the activity of genes may be why Black people in the US often have worse chronic pain than white people

Humans

28 March 2022

By Jason Arunn Murugesu
An enzyme adding methyl groups to DNA in a process called methylationLAGUNA DESIGN/SCIENCE PHOTO LIBRARY
Black people in the US have worse chronic pain than white people due in part to gene expression.
Chronic stress has previously been linked to racial discrimination, and can lead to changes in gene expression. Edwin Aroke at the University of Alabama at Birmingham and his colleagues collected blood samples from 98 people – half were Black and half were non-Hispanic white, and they had an average age of 45. Half the group had chronic lower back pain, … More

A mind-bending light and sound extravaganza is coming to a town near you, and it could help unravel the mysteries of the brain

Humans

23 March 2022

By Carissa Wong
Dreamachine’s light and sound show can produce intense hallucinations and a sense of calmBrenna Duncan
Dreamachine
Jennifer Crook
Unboxed FestivalAdvertisement
IN THE late 1950s, when altered states of consciousness were all the rage, the artist Brion Gysin invented a drug-free route to psychedelic euphoria. His Dreamachine – a spinning cylinder that shines flashing lights onto a viewer’s closed eyes – was intended as a shortcut to spiritual enlightenment for the masses.
Now, art producer Jennifer Crook has revisited Gysin’s invention as a sci-art multimedia experience. The aim is to produce a communal head trip that will not only expand visitors’ experience, but also probe the depths of human consciousness.
Crook got the idea for the project after having a transcendent experience while at a gig by electronic music artist Jon Hopkins. She went on to enlist Hopkins to provide the soundtrack to the updated Dreamachine, which will be touring the UK as part of the Unboxed Festival.
At the centre of the installation are vivid hallucinations created by the brain in response to specific sensory inputs. In the 1950s, the pioneering neuroscientist Grey Walter discovered that dreamlike hallucinations could be induced by lights flashing on closed eyelids at 8 to 12 hertz, the same frequency as the oscillations of “alpha” brainwaves when we are relaxed and wakeful with our eyes closed. Normally, when we open our eyes, these alpha waves are disrupted by visual inputs. Flashing lights at alpha wave frequencies on closed eyelids stimulates the optic nerve, but provides little visual information, and the brain responds by generating hallucinations.
Because of this, the Dreamachine can produce kaleidoscopic visions and a sense of calm. These hallucinations may also reveal a lot about the way the brain works. As part of the project, neuroscientists Anil Seth and David Schwartzman at the University of Sussex, UK, Dreamachine‘s light and sound show can produce intense hallucinations and a sense of calm are collecting the experiences of visitors, which they hope to use as a window into the workings of the brain. Seth is among the many scientists who believe that hallucinations are part of the way that our brains generate our conscious experience of the world.
One major question concerns perceptual diversity – how varied or similar our internal mental experiences may be. We know that we all see the world in different ways, but science can’t yet explain how and why. In an attempt to investigate this, an optional survey will ask participants to log their visual experiences using colour palettes, animations and shape selections.
Other questions will address the emotional aspects of the experience, which can be intense. Hopkins’s music alone, when played through 360-degree speakers around the audience, can give an eerie feeling of stepping out of time and into a state of being that usually comes with a meditative state.
As well as the physical exhibition, an online census will capture perceptual diversity from millions of people around the world, while a schools programme will be rolled out around the UK. Through activities and resources, children will be encouraged to ask questions about how they perceive the world and to explore how this differs from the experiences of others. The research team’s resident philosopher, Fiona Macpherson, says the goal is to show them how, in our differences, we are all connected.
This aim brings Dreamachine back to the ideals of its inventor, who hoped to give people the experience of being catapulted into a higher level of consciousness. Crook’s new vision is even more ambitious: to explore the depths of the human brain while realising the variation in our inner worlds and celebrating neurodiversity.
Dreamachine will tour London, Cardiff, Belfast and Edinburgh from May to September. Sign up for free tickets at dreammachine.world.

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The End of Astronauts is nigh, say astronomer Martin Rees and science writer Donald Goldsmith. They argue that, given the vast distances and the dangers involved in space travel, it is robots, not humans, that will lead us to the stars.
Kojima Productions/IGDB
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Death Stranding, from game creator Hideo Kojima, gets a substantial makeover in this director’s cut edition, which launches on PCs from 30 March. You play as Sam Bridges, who is on a mission to reunite a shattered world.Advertisement

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Are Plants Intelligent? asks philosopher Stella Sandford in this online talk from the Linnean Society of London. In light of new evidence, should we rethink our anthropocentric view of intelligence? 30 March, 12.30pm BST.

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Physicist and broadcaster Jim Al-Khalili discusses the power of wonder, the importance of overcoming our biases and the biggest mysteries in fundamental physics

Humans

23 March 2022

By Richard Webb
Nabil Nezzar
IT SEEMS nobody spends quite as much time discussing the joys of science as Jim Al-Khalili. Whether with guests on his BBC radio programme, The Life Scientific, in the documentaries he presents or with the students he teaches and mentors at the University of Surrey, UK, he is on an insatiable quest to find out “why”. He told us where this all started, why scientists need to question their own biases and about the importance of never growing up.
Richard Webb: To turn the tables a bit, what made you take up a life scientific?
Jim Al-Khalili: I guess my passion for science, well, physics, began in my early teens, when I was obsessed with football and discovering girls and thinking I’d one day play for my beloved Leeds United, who were a good team back then in the mid-1970s. But I suddenly fell in love with physics. It was like puzzle solving; it was common sense. With chemistry and biology, I had to remember stuff, and I’m terrible at remembering stuff. Physics also dealt with the big questions. Where does the universe come from? What does an atom look like? What’s inside a star? So from about the age of 13 or 14, I wanted to do physics. If I got to play for Leeds United, that would be nice, but I was going to be a physicist.
Your latest book is called The Joy of Science. Is that something you feel on a day-to-day basis?
It is, actually. Part of why I enjoy science communication is that I like doing the science. I like … More