A normal process

Reading What Is Regeneration by Jane Maienschein and Kate MacCord for New Scientist, 30 March 2022

Some animals are able to regrow lost or damaged parts. Crabs and lobsters regenerate whole tentacles and claws. Many more animals have lifecycles that involve the wholesale shedding and regrowth of certain tissues. (Unlike hydras and some worms, we humans cannot regrow our heads; but we can regrow our fingernails.)

Regeneration is such a peculiar property, it is surprisingly often ignored or discounted. The 18th-century French naturalist René-Antoine Réaumur spoke to people who made their living by fishing and was surprised when they dismissed stories of limb regeneration as mere “fables”. (His own somewhat bloodthirsty experiments on the local crayfish showed otherwise.)

So is regeneration a mere oddity? Is there any underlying logic to it? And what does it have to do with the grander mysteries of birth, death and development?

Jane Maienschein directs the History and Philosophy of Science Project at the Marine Biological Laboratory in Woods Hole, Massachusetts. Kate MacCord administers the centre’s effort to study how regeneration works across the scales of complex living systems. This book is their collaborative effort to understand why regeneration occurs when it does, and whether the regeneration of communities (the gut flora in your intestines after a course of antibiotics, say, or the regeneration of woodland after a forest fire) bears anything more than a semantic relationship with the kind of regeneration those crayfish enjoyed in the weeks following their unlucky encounter with M. Réaumur.

Regeneration turns out to be one of those simple, discrete, observable phenomena that, the closer we look at them, seem to vanish into thin air. For instance, when we think about regeneration, are we thinking about regeneration of structure, or regeneration of function, or both? How we think about regeneration impacts whether and where we think it occurs.

The authors’ history of regeneration begins with Aristotle and ends with Magdalena Zernicka-Goetz’s current work on cellular signalling. Their account pivots on Thomas Hunt Morgan (better known as a pioneer of chromosomal genetics) and in particular on his book Regeneration of 1901. Morgan, more than anyone before or since, attempted to establish clear boundaries around the phenomenon of regeneration. The terminology he invented remains useful. Restorative regeneration occurs in response to injury. Physiological regeneration describes replacement, as when a bird moults its feathers or an elk its antlers and a new structures grow in their place. Morphallaxis refers to cases of reshaping, as when a hydra, cut to pieces, reorganises itself into a new hydra without going through the normal processes of cell division.

Morgan’s observations and analysis established that the mechanisms of regeneration are not (as our authors put it) “a special response to changing environmental conditions but, rather, an internal normal process of growth and development. Nor is regeneration an evolutionary adaptation to external conditions, even though the process may be useful.”

So here’s the problem: if the mechanisms of regeneration cannot be distinguished from the mechanisms of growth and development, what’s to stop everything regenerating all the time? What dictates lawful regrowth, and why does it happen only in some tissues, only in some species, and only some of the time?

Far from being an interesting curio, regeneration turns out to be a window through which we glimpse the tightly imbricated (if not impossibly entangled) feedback loops from which the living world, at every scale, is composed. The words of geneticist François Jacob, writing in 1974 and quoted here, barely conveys the scale of the challenge the authors reveal: “every object that biology studies is a system of systems.”

No wonder that regeneration remains largely a mystery; that hopeful regenerative therapies using stem cells usually fail (and usually for unfathomable reasons); and that even the simplest ecosystems elude our control.

Maienschein and MacCord take fewer than 150 pages to anatomise the complexities and ambiguities that their simple question throws up. It is to their further credit that they do not make the biology any more complex or ambiguous than it has to be.

Free the sea

Reading Chris Armstrong’s A Blue New Deal for New Scientist, 16 February 2022

Chris Armstrong, a political theorist at the University of Southampton, believes that the institutions and laws that govern our oceans are too fragmented, too weak and too amenable to vested interests to address the inequalities that exist between developed and developing nations.

Nor, he says, do they protect the marine environment from destruction, and this at a time when there’s been a 30 per cent increase in ocean acidity (since 1900), when the global fishing effort has grown ninefold (between 1970 and 2008), and the globe’s pursuit of oil, gas and minerals is increasingly being directed off-shore.

Ocean governance has been shaped by two contrary impulses: the idea of the freedom of the high seas, given shape in Hugo Grotius’s The Free Sea of 1609; and the idea — rather more familiar to landlubbers — of enclosure, by which a coastal state is entitled to exclusive control and enjoyment of its immediate marine environment.

Grotius’s vision of oceanic free-for-all allows anyone with the wherewithal to exploit an ocean resource as much and as often as they desire. Armstrong allows that this was not entirely unreasonable, given the limited technology available at the time to even the wealthiest nations. Clearly, though, it needs reform for the 21st century, given only a handful of rich nations have access to the expensive technologies involved in sea-bed mining and mineral extraction.

Enclosure is perhaps the more recalcitrant tradition. The idea behind “territorial waters” is ancient, but Armstrong sensibly explains it by reference to the 1968 article by the ecologist Garrett Hardin, in which he claimed that “Freedom in a commons brings ruin to all”.

The trouble is, this isn’t true. The historical record is full of examples of resources held in common, and governed equitably for hundreds of years. The much vaunted “tragedy of the commons” is a piece of rhetoric, not a proven truth. And as Armstrong rightly points out, “the real tragedy for individual ‘commoners’ was enclosure itself, which saw them being evicted from the land by wealthy landowners.”

In 1994, a new Convention on the Law of the Sea established Exclusive Economic Zones extending for 200 nautical miles from nearly every shore. Within these zones, resources are subject to the jurisdiction of the coastal state. By this myopic reasoning, landlocked countries were excluded from a share of the spoils of the sea. (This matters, as access to the sea is essential for economic health. Armstrong points out that 9 of the world’s 12 poorest countries are landlocked). It did nothing to prevent richer nations from licensing, on predatory terms, rights over the EEZs of countries too poor to exploit their own territory. And it gave every state-owned atoll, rock, and island an exclusive patch of sea to exploit, extending 200 miles in every direction. And which states own these rocks? Former colonial powers, of course. Thanks to the 1994 convention, the United States, the United Kingdom, France, Russia and Australia now command the resources of more than 45 million square kilometres of ocean.

What can be done?

In 1959 a treaty established Antarctica as a place of peace and international cooperation — a commons in other words. Eight years later, the Outer Space Treaty of 1967 did the same for the worlds beyond our own. So it is not beyond our legal capacities, Armstrong argues, to govern our oceans along principles of common management, benefit sharing, and even technology transfer between rich and poor nations.

Where Armstrong comes unstuck is in his ideas for enforcement. It’s all very well to dream up a “World Ocean Authority” whose deliberations no state would have the power to veto or depart from. But what omnipotent and omniscient power will drive all this selfless sharing, I wonder? Not, I would bet, the destitute seamen of the Gulf of Thailand; nor the blue whales and other non-human stakeholders of our increasingly stressed oceans.

Are you experienced?

Reading Wildhood by Barbara Natterson-Horowitz and Kathryn Bowers for New Scientist, 18 March 2020

A king penguin raised on Georgia Island, off the coast of Antarctica. A European wolf. A spotted hyena in the Ngorongoro crater in Tanzania. A north Atlantic humpback whale born near the Dominican Republic. What could these four animals have in common?

What if they were all experiencing the same life event? After all, all animals are born, and all of them die. We’re all hungry sometimes, for food, or a mate.

How far can we push this idea? Do non-human animals have mid-life crises, for example? (Don’t mock; there’s evidence that some primates experience the same happiness curves through their life-course as humans do.)

Barbara Natterson-Horowitz, an evolutionary biologist, and Kathryn Bowers, an animal behaviorist, have for some years been devising and teaching courses at Harvard and the University of California at Los Angeles, looking for “horizontal identities” across species boundaries.

The term comes from Andrew Solomon’s 2014 book Far from the Tree, which contrasts vertical identities (between you and your parents and grandparents, say) with horizontal identities, which are “those among peers with whom you share similar attributes but no family ties”. The authors of Wildhood have expanded Solomon’s concept to include other species; “we suggest that adolescents share a horizontal identity,” they write: “temporary membership in a planet-wide tribe of adolescents.”

The heroes of Wildhood — Ursula the penguin, Shrink the hyena, Salt the whale and Slavc the wolf are all, (loosely speaking) “teens”, and like teens everywhere, they have several mountains to climb at once. They must learn how to stay safe, how to navigate social hierarchies, how to communicate sexually, and how to care for themselves. They need to become experienced, and for that, they need to have experiences.

Well into the 1980s, researchers were discouraged from discussing the mental lives of animals. The change in scientific culture came largely thanks to the video camera. Suddenly it was possible for behavioral scientists to observe, not just closely, but repeatedly, and in slow motion. Soon discoveries arose that could not possibly have been arrived at with the naked eye alone. An animal’s supposedly rote, mechanical behaviours turned out to be the product of learning, experiment, and experience. Stereotyped calls and gestures were unpacked to reveal, not language in the human sense, but languages nonetheless, and many were of dizzying complexity. Animals that we thought were driven by instinct (a word you’ll never even hear used these days), turned out to be lively, engaged, conscious beings, scrabbling for purchase in a confusing and unpredictable world.

The four tales that make up the bulk of Wildhood are more than “Just So” stories. “Every detail,” the authors explain, “is based on and validated by data from GPS satellite or radio collar studies, peer-reviewed scientific literature, published reports and interviews with the investigators involved”.

In addition, each offers a different angle on a wealth of material about animal behaviour. Examples of animal friendship, bullying, nepotism, exploitation and even property inheritance arrive in such numbers and at such a level of detail, it takes an ordinary, baggy human word like “friendship” or “bullying” to contain them.

“Level playing fields don’t exist in nature”, the authors assert, and this is an important point, given the book’s central claim that by understanding the “wildhoods” of other animals, we can develop better approaches “for compassionately and skillfully guiding human adolescents toward adulthood.”

The point is not to use non-human behaviour as an excuse for human misbehaviour. Lots of animals kill and exploit each other, but that shouldn’t make exploitation or murder acceptable. The point is to know which battles to pick. Making young school playtimes boring by quashing the least sign of competitiveness makes little sense, given the amount of biological machinery dedicated to judging and ranking in every animal species from humans to lobsters. On the other hand, every young animal, when it returns to its parents, gets a well-earned break from the “playground” — but young humans don’t. They’re now tied 24-7 to social media that prolongue, exaggerate and exacerbate the ranking process. Is the rise in mental health problems among the affluent young triggered by this added stress?

These are speculations and discussions for another book, for which Wildhood may prove a necessary and charming foundation. Introduced in the first couple of pages to California sea otters, swimming up to sharks one moment then fleeing from a plastic boat the next, the reader can’t help but recognise, in the animals’ overly bold and overly cautious behaviour, the gawkiness and tremor of their own adolescence.