“Spectacular, ridiculous, experimental things”

Reading The Tomb of the Mili Mongga by Samuel Turvey for New Scientist, 6 March 2024

Pity the plight of evolutionary biologist Samuel Turvey, whose anecdotal accounts of fossil hunting in a cave near the village of Mahaniwa, on the Indonesian island of Sumba, include the close attentions of “huge tail-less whip scorpions with sickening flattened bodies, large spiny grabbing mouthparts, and grotesquely thin and elongated legs”.

Why was a conservation biologist hunting for fossils? Turvey’s answer has to do with the dual evolutionary nature of islands.

On the one hand, says Turvey, “life does spectacular, ridiculous, experimental things on islands, making them endlessly fascinating to students of evolution.”

New Caledonia, a fragment of ancient Gondwana, boasts bizarre aquatic conifers and even shrubby parasitic conifers without any roots. Madagascar hosts a lemur called the aye-aye; a near primate equivalent to the woodpecker. But my personal favourite, in a book full of wonders, pithily described, is the now extinct cave goat Myotragus from predator-free Majorca and Menorca. Relieved of the need to watch its back, it evolved front-facing eyes, giving it the disconcerting appearance of a person wearing a goat mask.

But there is a darker side to island life: it’s incredibly vulnerable. The biggest killers by far are visitations of fast-evolving diseases. European exploration and colonisation between the 16th and 19th centuries decimated the human populations of Pacific archipelagos, as a first wave of dysentery was followed by smallpox, measles and influenza. Animals brought on the trip proved almost as catastrophic to the environment. Contrary to cliche, westerners on the island of Mauritius did not hunt the dodo to extinction; rats did. And let’s not forget Tibbles, the cat that’s said to have single-handedly (pawedly?) wiped out the Stephens Island wren, a tiny flightless songbird, in 1894.

There are lessons to be learned here, of course, but Turvey’s at pains to point out that islands are accidents waiting to happen. Islands are by their very nature sites of extinction. They may be treasure-troves of evolutionary innovation, but most of their treasures are already extinct. As for conserving their wildlife, Turvey wonders how, without a good understanding of the local fossil record, “we even define what constitutes a ‘natural’ ecosystem, or an objective restoration target to aim for”.

A tale of islands and their ephemeral wonders would alone have made for an arresting book, but Turvey, a more-than-able raconteur, can’t resist spicing up his account with tales of Sumba’s resident mythical wild-men, the “Mili Mongga”, who, it is said, used to build walls and help out with the ploughing — until their habit of stealing food got them all killed by the infuriated human population.

Why should we pay attention to such tales? Well, Sumba is only about 50 kilometres south of Flores, where a previously unknown (and, at just over a metre tall, ridiculously small) hominin was unearthed by an Australian team in 2003.

If there were hobbits on Flores, might there have been giants on Sumba? And might surviving mili mongga still be lurking in the forests?

Turvey uses the local island legends to launch fascinating forays into the island’s history and anthropology, to explain why large animals, fetched up on islands, grow smaller, while small animals grow larger, and also to have an inordinate amount of fun, largely at his own expense.

When one villager describes a mili mongga skull as being two feet long, and its teeth “as long as a finger”, “I got the feeling,” says Turvey, ”that there might now be some exaggeration going on.” Never say never, though: soon Turvey and his long-suffering team are following gamely along on missions up crags and past crocodile-infested swamps and into holes in the ground — sometimes where other visitors, from other villages, habitually go to relieve themselves.

“There was the cave that some village kids told us contained a human skull, which turned out to be a rotten coconut under some bat dung,” Turvey recalls. “There was the cave that was sacred, which seemed to mean that no one could remember exactly where it was.”

Turvey’s more serious explorations unearthed two new mammal genera (both ancestral forms of rat). It goes without saying, I should think, that they did not bring back evidence of a new hominin. But what’s not to enjoy about a tall tale, especially when it’s used to paint such a vivid and insightful portrait of a land and its people?

Delight and devilry

Reading Douglas Futuyma’s How Birds Evolve for new Scientist, 7 December 2022

In Douglas Futuyma’s evolutionary history of birds, the delight is in the detail, and some of the devilry too — this is not a light read. Futuyma tells a double tale: he explains how the study of birds advanced our understanding of evolution, and he shows how advances in evolutionary science solve some long-standing ornithological mysteries, even as they throw up others.

He has written How Birds Evolve for birders, and being a birder himself (he began bird-spotting around the age of eleven in New York’s public parks), he knows just how fiercely the birding bug can bite. Many are half-way to being field scientists already, and many celebrated field scientists — from Ernst Mayr to Konrad Lorenz to Niko Tinbergen — have been birders.

“I suspect few of my teachers in the 1960s imagined that we would be studying birds by combining information from geology and molecular biology — disciplines that are miles apart,” says Futuyma, giving the reader an early hint of the complexities to come.

Birds are a curious, and curiously productive field of study for evolutionary biologists: less useful in understanding the mechanisms of evolution than insects, plants, and bacteria because they don’t reproduce as quickly, but, being various and everywhere, vital to the study of behaviour, longevity, ecology, speciation, cultural evolution and a host of other specialisms.

The ability to study populations and how they interact gave evolutionary biologists a foretaste of what their science would become. “The models of how variation might persist” Futuyma remarks, “were developed by evolutionary biologists who might not have known a hawk from a handsaw but were adept in mathematics.” Applying lessons from birds to ourselves, though risky, has also proved both irresistible and, at least in the science’s early stages, highly productive. In pondering human evolution, Darwin developed the idea of sexual selection, which takes up more than half his The Descent of Man of 1871. “Darwin devotes four full chapters to birds and cites at least 170 species,” Futuyman points out. “Birds provided more evidence for his ideas about sexual selection than any other group of animals”.

To grapple with bird diversity, one pretty much has to conjure up an idea of evolution. Peculiar and apparently inutile features abound in the bird world, a sure sign of unceasing adaptation. There are also, to complicate matters, many instances of convergent evolution. Feathers may have evolved only once, and through a bizarre genetic accident at that. (They don’t arise easily, as we once assumed, from reptilian scales.) Feather and wing shapes, however, recur again and again in even distantly related species. Darwin once predicted: “Our classifications will come to be, as far as they can be so made, genealogies,” but even his credulity would have been stretched by the news that flamingoes are related genetically to grebes.

“I don’t know how similar to birds a creature would have to be for us to call it an “avioid” or an “ornithoid,” Futuyman speculates, but for it “to be bipedal with feathers, toothless kinetic jaws, highly developed vision, a gizzard, and a high constant body temperature… I think… is very unlikely indeed.”

Futuyma unpacks the story of evolutionary science alongside the story of how birds evolved, acquiring bipedal locomotion and simple filamentous feathers as Dinosauria, then clavicles fused into a wishbone in Theropoda, on and on, until we arrive at what we might as well call the modern bird, with its large, keeled breastbone, rapid growth, and unfeasibly lightweight construction.

How Birds Evolve is not meant to be an introduction to birds (though one imagines readers of this magazine would lap it up). It is personable, entertaining and deeply passionate about its subject.

Futuyma, the author of two successful textbooks about evolution, is out to inspire, and his comprehensive book more than makes up in wonder what it might lack in an easy and seductive narrative.

Being kind to the blarney

Reading Yuval Noah Harari’s How Humans Took Over the World (Unstoppable Us 1) for the Telegraph, 9 October 2022

“And just think how sad the last mammoth must have been all on her own,” writes Yuval Noah Harari, as he invites his pre-teen audience to contemplate our species’ long track record in wiping out countless varieties of big animal (giant flightless birds; elephantine sloths; the list is long).

Harari is spreading his young person’s history of humankind across four illustrated volumes. This is the first, and describes how we managed to exterminate our way to planetary dominance (so a certain mawkishness is allowable). Following the Bauplan of Harari’s 2011 adult bestseller Sapiens: A Brief History of Humankind, we can reasonably look forward to a triumphalist futuristic fourth volume in which all the monsters that terrified and/or fed our ancestors are resurrected by our CRISPR-wielding post-human descendants and released into some sort of 3D-printed world zoo.

Why survey such a vast sweep of evolutionary history through the keyhole of “what we really know”? Why not say what you’ve got to say, and leave the error-correction to your young reader’s own curiosity and further reading? When I was a kid, Patrick Moore was still writing about Venus’s already rather unlikely world ocean. I was inspired by such unchained speculation, and I don’t think I sustained any lasting intellectual harm.

But we are where we are: the world is haunted by the spectre of untruth and is besotted with the wisdom of crowds, and Harari is at pains in his afterword to point out how carefully staff at Penguin and his own “social impact company” Sapienship weighed every sentence and every illustration, lest it might misrepresent something or “hurt people”.

As a consequence, How Humans Took Over the World is, for all its many strengths, one of the least odd books I have ever read.

How Humans Took Over the World is an easy-to-read epic that sets out to be scrupulously truthful about what we do and do not know about the past. In simple, direct terms, Harari explains that we’re the only species that believes stories; stories enabled cooperation; and cooperation made it possible for us to smother and consume large amounts of the planet.

Harari’s ebullience as a storyteller is infectious. No sooner does he dry his eyes over the fate of the mammoth, than he is gleefully explaining how easy they were to get rid of. (With that long a gestation period, and that small a herd, you only had to kill a couple of mammoths a year to wipe them out.)

Harari’s concludes that we’re not a very nice species. This is risky, if only because self-hate is cheap and saves us the trouble of doing anything or changing anything about ourselves. The gloomy shade of Jean-Jacques Rousseau hovers over Harari’s dismissal of religion as a means by which powerful hominins cozened an unfair quantity of bananas from their weaker brethren. The idea that religion might be humanity’s millennia-old effort to tell uplifting stories about itself, all in the teeth of cosmic meaninglessness and the inevitability of death, gets no look-in here, though Harari still spends an inordinate amount of time being kind to the blarney and tosh spun by animists and shamans, those snake-oil salesmen of yore.

Harari’s setting us up for a thunderous and inspiring last chapter, in which we see Homo sapiens poised to use its storytelling superpower to more constructive effect.

If thousands of people believe in the same story, then they’ll all follow the same rules, and this is why we rule the world (“whereas poor chimps are locked up in zoos”).

To save the world we have been so busy consuming, we need to come up with a story about ourselves that’s better than the ones we’ve told each other in the past (or, to be less judgemental about it, a story that’s better suited to our planet’s present).

“If you can invent a good story that enough people believe,” Harari writes, “you can conquer the world.”

It is unlikely that this will be written by Harari. Though he’s packaged as a seer, there’s little in his work that is truly surprising or sui generis.

His chief skill — displayed here even more remarkably than in his work for adults — is his ability to spin complex material into a rollicking tale while still telling the truth.

“The idea that life is absurd bothers him”

Reading Life As Told by a Sapiens to a Neanderthal by Juan José Millás and Juan Luis Arsuaga for the Telegraph, 27 July 2022

In 2013 the oldest known human DNA was discovered, in a complex of caves in the Sierra de Atapuerca in northern Spain. It belongs to an early hominid, Homo heidelbergensis, who lived 400,000 years ago, and to whom we owe the invention of the fireplace.

Arsuaga has built an illustrious career around excavations in Atapuerca, a site humans have occupied continuously for a million years, from the dawn of Homo sapiens to the bronze age. He knows a lot about how humans evolved, and he is an eloquent communicator. “As he talked,” the novelist Juan José Millás recalls, “I realised what a great sense of the theatrical Arsuaga had. He was a master of oral storytelling. He knew when he had his audience, and when he was running the risk of losing them. He endeared himself by combining intellectual precision with a kind of helplessness.”

It’s Aruaga’s eloquence that first persuaded Millás that the two of them should collaborate on a book — a Boswellian confection in which Millás (humble, curious, a klutz, and frequently brow-beaten) follows Arsuaga around with a dictaphone capturing the great man’s observations. “In Spain,” he remarks, early on, “there are two principal periods: the first runs from the Neolithic to 1958, at which point the social planning by the Opus Dei technocrats comes in. Until then, the countryside was a place full of people, full of voices, life here was not a sad thing, there were children running around. It would be like walking down the street. By 1970, the countryside was empty, there was nobody left.”

Millás casts Arsuaga as the representative of Homo sapiens: articulate, eclectic, self-aware and tragical. Millás casts himself as Homo neanderthalis, not quite as quick on the uptake as his more successful cousin. Neanderthals are a species not exactly lost to history (Sapiens and Neanderthals interbred, after all) but no longer active in it, either.

The idea is that Arsuaga the high-brow leads our beetle-browed narrator hither and thither across northern Spain, on foot or in his trusty Nissan Juke, up lost valleys (to understand the evolution of hunting) and through deserted playgrounds (to grasp the mechanics of bipedalism), past market stalls (to grasp the historical significance of diet) and into a sex shop (to discuss the relative size of primate testicles) and building, bit by bit, a dazzling picture of the continuities that exist between our ancient and contemporary selves.

For many, the devil will be in the detail. Take, for example, Millás’s Neanderthals. He is not exactly wrong in what he says about them, but he is writing, in the most general and allusive terms, into a field that is developing frighteningly fast. It‘s hard, then, for us to know how literally to take the author’s showier gestures. Millás says, about that famous interbreeding, that “The Sapiens, being the smart ones, did it out of vice, while the Neanderthals, who were more naïve, did it out of love.” With Neanderthal intelligence and sociality a topic of so much fierce debate, such statements as this may be met with more scepticism than appreciation.

This is as much a buddy story as it is a virtuosic work of popular science. In unpacking our evolutionary past, Millas also brings his human subject to light. Arsuaga holds to the tragic view of life espoused by the fin de siecle Spanish essayist Miguel de Unamuno. Millás, a more common-or-garden depressive, finds Arsuaga’s combination of high spirits and annoyance hard to read. Deposited on the outskirts of Madrid, and half suspecting he’s been actually thrown out of Arsuaga’s Nissan, Millás realises that the palaeontologist “experiences sudden bursts of sadness that he sometimes conceals beneath an ironic demeanour, and sometimes beneath passing bad moods. I think the idea that life is absurd bothers him.”

Aruaga’s tragic sense entends to the species. We are the self-domesticating species: “To the Neanderthal,” he says, “the Sapiens must have seemed like a teddy bear.” We have evolved social complexity by shedding the adult seriousness we observe in less social mammals. (“I’ve been to Rwanda, looking at old gorillas,” says Aruaga, “and I can assure you they don’t play at all, they don’t laugh at anything.”) Over evolutionary time, we have become more playful, more infantile, more docile, and we have done this by executing, imprisoning and marginalising those who exhibit an ever-expending list of what we consider anti-social traits. So inanity will one day conquer all.

I wish Millás was a less precious writer. Very early on the pair arrive at a waterfall. “What had we come here for?” Millás writes: “in principle, to see the waterfall, and perhaps so the waterfall could see us, too.” Such unredeemable LRBisms are, I suppose, a form of protective coloration, necessary for a novelist and poet of some reputation: an earnest of his devotion to propah lirtritchah.

It’s when Millás forgets himself, and erases the distance he meant to maintain between boffins and scribblers, that Life becomes a very special book indeed: a passionate, sympathetic portrait of one life scientist’s world view.

The worst day ever

Reading Riley Black’s The Last Days of the Dinosaurs for New Scientist, 20 April 2022

Welcome to Hell Creek, in what is now Montana. Readers had best not get too attached to the inhabitants dreamt into being in the first chapter of The Last Days of the Dinosaurs: the Tyrannosaurus rex, “her reddish brown hide now draped in orange and gold from the low-angled light of the evening sun”; the low-slung herbivore Ankylosaurus, defending herself with a tail club the size of a car tyre; the new-born Alamosaurus sanjuanensis chick, that will never get to grow into one of the largest animals to ever walk the Earth.

Tomorrow, a seven-mile-wide meteor will plough into the ancient Yucatán, triggering the extinction of around three quarters of all species on Earth. Along with all non-avian dinosaurs, great batwinged pterosaurs will perish; later, invertebrates like ammonites will stutter and stop in seas made corrosive by acid rain. Most early mammals — those that didn’t go up in flames, or get blasted off into outer space — will eventually starve; and with them, most lizards, snakes, and birds.

Subsequent chapters offer glimpses of the aftermath, each separated by an exponentially longer interval. An hour after impact and in Hell Creek, over 4,500 kilometres away from the impact, a puzzled Ankylosaurus fights for its footing at the edge of a trembling lake. Safe in her burrow, a squirrel-like Mesodma sleeps through a day of pulsing, planetary conflagration. A month in, and little two-toed Acheroraptors are poking about amongst the decaying debris, unaware of the cold and hunger to come.

Time accelerates. A year, a hundred years, a thousand years go by. We venture far from Hell Creek, many times, and learn much about dinosaurs and their long history, about the mechanisms of evolution and climate, and about the deep history of our planet. We learn to abandon old notions of a planet healing itself, or of life returning to some ideal degree of diversity. Mass extinctions are not “opportunities”, and when living designs are lost, in the great game of adaptation and extinction, they stay lost. Life got through by the skin of its teeth.

Hell Creek remains central throughout, as is only reasonable, since its geology appears to record in such extraordinary detail the events immediately following the giant Chicxulub asteroid’s impact. We glimpse it as an Eden, gardened by towering herbivores. We see it go up in flames. We say goodbye to the place as new plants smother and entangle it, creating the jungle environments from which complex behaviours and communities — both primate and avian — will be born. Throughout, the author’s shifting cast of characters remains vivid and charming.

Indeed, it’s as if Black — a palaeontologist and prolific writer, and no doubt familiar to many readers for her Laelaps blog — had set up camp in the very heart of the valley. This is palaeontology written with the immediacy of natural history.

In a long appendix, Black explains what’s real in this book, and what she’s made up. No need to be disconcerted. Without a leavening of intelligent speculation, palaeontologists have never been able to say anything useful. it’s a point Black makes splendidly, with reference to an illustrated study from 1863, The World Before the Deluge.

This book was published just a couple of years after the discovery of the first decent fossilised skeleton of Archaeopteryx — a previously missing link between reptiles and birds. The only problem was the head was missing. “Did Archaeopteryx have a beak? Teeth? Both? Neither? There was no way to answer the question,” Black explains. “And so The World Before the Deluge portrayed Archaeopteryx flying high above Jurassic conifers totally headless.”

Black’s approach is much more sensible, adding to The Last Days of the Dinosaurs whatever she needs — a head here, a behaviour there — to give us living, more-or-less reliable glimpses into the days after the worst day ever suffered by life on Earth.

 

Not quite a coincidence

Reading Antone Martinho-Truswell’s The Parrot in the Mirror for New Scientist, 9 March 2022

Organisms adapt over evolutionary time to their changing surroundings. This creates, over time, a living world of quite jaw-dropping diversity. It also generates some astonishing coincidences — if “coincidence” is quite the right word to describe how two quite unlike species, adapting to identical environments, end up looking and behaving the same. For instance, the pangolins of Africa and the armadilloes of South America look like close cousins; in fact they’re more closely related to humans than they are to each other.

Convergent evolution doesn’t have to be so visually obvious. Take humans and birds: few readers will take on trust Sydney-based zoologist Martinho-Truswell’s assertion that we “look like a strangely featherless bird”.

By the time I finished The Parrot in the Mirror, though, I found that image both compelling and reasonable. Martinho-Truswell explores the traits shared by humans and birds, from our unusual longevity to our advanced social skills, from our parenting styles to our intelligence and even our use of language. These, the author argues, are all extraordinary examples of convergent evolution at work.

Crudely, Martinho-Truswell’s argument goes like this:

Once birds could fly, they could elude almost all predators. And since they were unlikely to be eaten in any given year, it made sense for birds to go on living, producing more eggs and offspring. Increased longevity followed. With longevity came increased intelligence. Long-living animals need to be smart because they get to be the parents of young who develop over a longer period. And because longer development requires a bigger egg and a bigger yolk sac, and because an egg can only get so big, most birds hatch out very immature, helpless young, that require enormous amounts of care. This care is provided by pair bonded parents, sometimes supplemented by a larger community, hence the evolution of complex social behaviour and language (or song, at any rate).

The human story is a twisted mirror-image of the avian one. Communal behaviour among primates promoted the evolution of intelligence, and this reduced the likelihood of predation. Longevity followed, boosting intelligence further, to the point where big-brained human young have to be born immature and helpless so as not to kill their mothers in childbirth.

For different reasons, then, humans and birds evolved measurable intelligence. But how do we compare our abilities? Can we even talk about bird smarts and human smarts in the same sentence?

Martinho-Truswell’s handling of this subject is very well done. A balance has to be stuck between precision and imagination. On the one hand, a duckling’s ability to imprint upon its mother shortly after the moment of its birth puts it well ahead of chimpanzees, parrots, pigeons, crows and even human children, but this one hardwired ability doesn’t necessarily make the duckling more intelligent. On the other hand, it would be a dull observer indeed that did not see in Irene Pepperberg’s thirty-year study of language use in Alex, an African Grey parrot, quite staggering evidence of advanced cognition. (Alex not only asked questions; it asked them, and got annoyed if people offered dumb responses.)

Containing the niceties of convergent evolution in a straightforward narrative is not easy. Evolutionary causes and effects do not follow each other in neat, storybook fashion, and there’s always the temptation, reading this book, to take Martinho-Truswell’s acts of narrative shorthand at face value and suppose that humans, 50 million years behind parrots in the evolution of intelligence, somehow became more human by actually mimicking their distant avian cousins. (Distant cousins indeed, by the way: the last common ancestor of birds and mammals died out 320 million years ago.)

But it is surely better to be very slightly misled by a gripping story than to be bludgeoned by a dull one. Martinho-Truswell has written a superb introduction to a surprisingly complex and fraught field of study. Having read it, you will not look at yourself in the mirror in quite the same way.

 

Clay moulded by time

Reading Thomas Halliday’s Otherlands: A world in the making for the Telegraph, 5 February 2022

Earlier books have painted tableaux of life at other epochs, but few ever got the scale right. Thomas Halliday’s visions are monstrous.

Halliday is a paleoecologist. That’s a branch of biology, which in turn has become a troublesome cousin of physics, borrowing its technology as it penetrates the living machineries of heritability and development. “My own scientific work,” writes Birmingham-based researcher Thomas Halliday, “has mostly happened in basement museum collections and within computer algorithms, using shared anatomical features to try and work out the relationships among the mammals that lived in the aftermath of the last mass extinction.”

But Halliday is also a child of Rannoch — that glacier-scoured landscape of extinct volcanoes that dominates Scotland’s central highlands. And anyone familiar with that region will see instinctively how it underpins this epic near-hallucinatory natural history of the living earth.

Otherlands works backwards through the history of life, past the icebound Pleistocene 20,000 years ago and the Chicxulub asteroid strike 66 million years ago, past the deeply weird Triassic and the lush Devonian, all the way back to the first stirrings of multicellular life in the Ediacaran, 550 million years ago.

Many readers will come for the jump-scares. The paleocene Mesodma, which looks like a rodent until it opens its mouth, revealing a terrifying notched tooth, as though a buzzsaw were buried in its gum. The Gigatitan, a Triassic forerunner of the grasshopper, whose stridulations generate a bullfrog-like baritone song. The Tully Monster, the herring of the Carboniferous, with a segmented torpedo body, two rippling squid-like tail fins and at the front, “something like the hose of a vacuum cleaner, with a tiny tooth-filled grabbing claw at its end”.

Halliday weaves these snapshots of individual plants and animals into a vision of how carbon-based life continually adapts to its shifting, spinning home. It’s a story that becomes increasingly uncanny as it develops, as how could it not? In the normal course of things, we only ever get to see a single snapshot from this story, which is governed by rules that only start to make sense in geological time.

Anyone who’s looked at a crab feeding — a wriggling mass of legs that are tongues that are teeth — will not be surprised to learn that arthropods are the Swiss Army knives of the animal world, “with each segment containing a flexible, jointed appendage that can be adapted to a huge variety of functions.” But arthropods are weird-looking to begin with.

It’s when the cuddly end of nature starts to morph that the flesh begins to creep. In Gargano, that was once an island in the Mediterranean, home to dwarf elephants, giant swans and metre-long barn owls, we learn that everything on an island tends towards one particular size.

In the cold, though, this process goes into reverse. Getting big means your bulk can keep you warm for longer. Getting small means you can hibernate. Seymour Island in Antarctica, in the Eocene, boasted much wildlife, but nothing in size between a rabbit and a sheep.

So far, so Alice-like. More unnerving are the ways in which living things, quite unrelated, converge to exploit similar settings. The pangolins of Africa and South Asia are more closely related to humans than they are to South American armadilloes. At first glance, though, you’d be hard pressed to tell these two animals apart.

If nature fitted together neatly, this sort of thing might not seem so disquieting. But things don’t fit together. There is no balance, just a torrent of constant change, and plants and animals lost in its eddies. When threatened, the slow loris raises its arms up behind its head, shivers and hisses. Why? Because it’s trying to look like a cobra, though the ranges of slow loris and cobra haven’t overlapped in tens of thousands of years.

Slowly, but very surely, the the six-metre long sea serpents of the Triassic come to see almost benign next to the Giant Dormouse or Terrible Moon-Rat which, in their uncanny resemblance to familiar animals, remind us that we humans, too, are clay moulded by time.

In the story of life on Earth, the activities of Homo sapiens are an eyeblink. We’re a sudden, short-lived, energetic thing, like a volcanic eruption, like a rock from space. It doesn’t really matter what they are, or whether they take a split-second, a couple of hundred years, or a few thousand years to wreak their havoc. Sudden energetic things destroy.

But rather than fall into the contemporary cliche and attempt to conjure up some specious agency for us all — “you too are a governor of the planet!” — Halliday engages us as Victorian writers once did, filling us with wonder, not anxiety — and now with added nuance, and better evidence to hand. The chapter “Deluge”, on the filling of the Mediterranean basin in the Miocine, and the chapter “Cycles” describing Eocene polar rainforests, were personal favourites, dazzling me to the point where I wondered, dizzily, how accurate these visions might be.

I don’t mean that Halliday has taken short cuts. On the contrary: the story he tells is handsomely evidenced. I mean only that his story will eventually date. Not far from where I live, Benjamin Waterhouse Hawkins sculpted the first full-scale representations of dinosaurs, setting them in a landscape designed by Joseph Paxton, for the delectation of visitors to the Crystal Palace, once it relocated near Penge.

People now point and titter at Hawkins’s inaccuracies — the horn on one beast turns out to be the thumb belonging to another and so on — but what’s really staggering is how accurate his models are, given the evidence available at the time.

Halliday stands on the shoulders of Hawkins and other giants. He knows about dinosaur coloration, and dinosaur vision (they could see into the ultra-violet). He can trace the wax on fossilised leaves, and tell you how the seasons worked, and about the prevailing winds. He can trace our ancient insectivorous past through genes we all carry that code for digesting chitin. Picking among countless recent discoveries, he can even tell you how four-limbed flying pterosaurs came in to land (“hind-feet first, a jump, skip and hop to a stop”).

I wonder what Halliday cannot yet know?

As the author says, “Nothing provokes debate quite like the hunting of monsters.”

Life dies at the end

Reading Henry Gee’s A (Very) Short History of Life on Earth for the Times, 23 October 2021

The story of life on Earth is around 4.6 billion years long. We’re here to witness the most interesting bit (of course we are; our presence makes it interesting) and once we’re gone (wiped out in an eyeblink, or maybe, just maybe, speciated out of all recognition) the story will run on, and run down, for about another billion years, before the Sun incinerates the Earth.

It’s an epic story, and like most epic stories, it cries out for a good editor. In Henry Gee, a British palaeontologist and senior editor of the scientific journal Nature, it has found one. But Gee has his work cut out. The story doesn’t really get going until the end. The first two thirds are about slime. And once there are living things worth looking at, they keep keeling over. All the interesting species burn up and vanish like candles lit at both ends. Humans (the only animal we know of that’s even aware that this story exists) will last no time at all. And the five extinction events this planet has so far undergone might make you seriously wonder why life bothered in the first place.

We are told, for example, how two magma plumes in the late Permian killed this story just as it got going, wiping out nineteen of every species in the sea, and one out of every ten on land. It would take humans another 500 years of doing exactly what they’ve been doing since the Industrial Revolution to cause anything like that kind of damage.

A word about this: we have form in wiping things out and then regretting their loss (mammoths, dodos, passenger pigeons). And we really must stop mucking about with the chemistry of the air. But we’re not planet-killers. “It is not the Sixth Extinction,” Henry Gee reassures us. “At least, not yet.”

It’s perhaps a little bit belittling to cast Gee’s achievement here as mere “editing”. Gee’s a marvellously engaging writer, juggling humour, precision, polemic and poetry to enrich his impossibly telescoped account. His description of the lycopod forests that are the source of nearly all our coal — and whose trees grew only to reproduce, exploding into a crown of spore-bearing branches — brings to mind a battlefield of the First World War, a “craterscape of hollow stumps, filled with a refuse of water and death… rising from a mire of decay.” A little later a Lystrosaurus (a distant ancestor of mammals, and the most successful land animal ever) is sketched as having “the body of a pig, the uncompromising attitude toward food of a golden retriever, and the head of an electric can opener”.

Gee’s book is full of such dazzling walk-on parts, but most impressive are the elegant numbers he traces across evolutionary time. Here’s one: dinosaurs, unlike mammals, evolved a highly efficient one-way system for breathing that involved passing spent air through sacs distributed inside their bodies. They were air-cooled, which meant they could get very big without cooking themselves. They were lighter than they looked, literally full of hot air, and these advantages — lightweight structure, fast-running metabolism, air cooling — made their evolution into birds possible.

Here’s another tale: the make-up of our teeth — enamel over dentine over bone — is the same as you’d find in the armoured skin of the earliest fishes.

To braid such interconnected wonders into a book the size of a modest novel is essentially an exercise in precis, and a bravura demonstration of the editor’s art. Though the book (whose virtue is its brevity) is not illustrated, there six timelines to guide us through the scalar shifts necessary to comprehend the staggering longueurs involved in bringing a planet to life. Life was entirely stationary and mostly slimy until only about 600 million years ago. Just ten million years ago, grasses evolved, and with them, grazing animals and their predators, some of whom, the primates, were on their way to making us. The earliest Sapiens appeared just over half a million years ago. Only when sea levels fell, around 120,000 years ago, did Sapiens get to migrate around the planet.

As one reads Gee’s “(very) short history”, one feels time slowing down and growing more granular. This deceleration gives Gee the space he needs to depict the burgeoning complexity of life as it spreads and evolves. It’s a scalar game that’s reminiscent of Charles and Ray Eames’s 1967 films *Powers of Ten*, which depicted the relative scale of the Universe by zooming in (through the atom) and out (through the cosmos) at logarithmic speed. It’s a dizzying and exhilarating technique which, for all that, makes clear sense out of very complex narratives.

Eventually — and long after we are gone — life will retreat beneath the earth as the swelling sun makes conditions on the planet’s surface impossible. The distinctions between things will fall away as life, struggling to live, becomes colossal, colonial and homogenous. Imagine vast subterranean figs, populated by evolved, worm-like insects…

Then, your mind reeling, try and work out what on earth people mean when they say that humans have conquered and/or despoiled the planet.

Our planet deserves our care, for sure, because we have to live here. But the planet has yet to register our existence, and probably never will. We are, Gee explains, just two and a half million years into a series of ice ages that will last for tens of millions of years more. Our species’ story extends not much beyond one of these hundreds of cycles. The human-induced injection of carbon dioxide “will set back the date of the next glacial advance” — and that is all. 250 million years hence, any future prospectors (and they won’t be human), armed with equipment “of the most refined sensitivity”, might — just might — be able to detect that, a short way through the Cenozoic Ice Age, *something happened*, “but they might be unable to say precisely what.”

It takes a long time to bring complex life to a planet, and complex life, once it runs out of wriggle room, collapses in an instant. Humans already labour under a considerable “extinction debt” since they have made their habitat (“nothing less than the entire Earth”) progressively less habitable. Most everything that ever went extinct fell into the same trap. What makes our case tragic is that we’re conscious of what we’ve done; we’re trying to do something about it; and we know that, in the long run, it will never be enough.

Gee’s final masterstroke as editor is to make human sense, and real tragedy, from his unwieldy story’s glaring spoiler: that Life dies at the end.

Tally-ho!

Reading Sentient by Jackie Higgins for the Times, 19 June 2021

In May 1971 a young man from Portsmouth, Ian Waterman, lost all sense of his body. He wasn’t just numb. A person has a sense of the position of their body in space. In Waterman, that sense fell away, mysteriously and permanently.

Waterman, now in his seventies, has learned to operate his body rather as the rest of us operate a car. He has executive control over his movements, but no very intimate sense of what his flesh is up to.

What must this be like?

In a late chapter of her epic account of how the senses make sense, and exhibiting the kind of left-field thinking that makes for great TV documentaries, writer-director-producer Jackie Higgins goes looking for answers among the octopuses.

The octopus’s brain, you see, has no fine control over its arms. They pretty much do their own thing. They do, though, respond to the occasional high-level executive order. “Tally-ho!” cries the brain, and the arms gallop off, the brain in no more (or less) control of its transport system than a girl on a pony at a gymkhana.

Is being Ian Waterman anything like being an octopus? Attempts to imagine our way into other animals’ experiences — or other people’s experience, for that matter — have for a long time fallen under the shadow of an essay written in 1974 by American philosopher Thomas Nagel.

“What Is It Like to Be a Bat?” wasn’t about bats so much as to do with consciousness (continuity of). I can, with enough tequila inside me) imagine what it would be like for me to be a bat. But that’s not the same as knowing what’s it’s like for a bat to be a bat.

Nagel’s lesson in gloomy solipsism is all very well in philosophy. Applied to natural history, though — where even a vague notion of what a bat feels like might help a naturalist towards a moment of insight — it merely sticks the perfect in the way of the good. Every sparky natural history writer cocks a snook at poor Nagel whenever the opportunity arises.

Advances in media technology over the last twenty years (including, for birds, tiny monitor-stuffed backpacks) have deluged us in fine-grained information about how animals behave. We now have a much better idea of what (and how) they feel.

Now, you can take this sort of thing only so far. The mantis shrimp (not a shrimp; a scampi) has up to sixteen kinds of narrow-band photoreceptor, each tuned to a different wavelength of light! Humans only have three. Does this mean that the mantis shrimp enjoys better colour vision than we do?

Nope. The mantis shrimp is blind to colour, in the human sense of the word, perceiving only wavelengths. The human brain meanwhile, by processing the relative intensities of those three wavelengths of colour vision, distinguishes between millions of colours. (Some women have four colour receptors, which is why you should never argue with a woman about which curtains match the sofa.)

What about the star-nosed mole, whose octopus-like head is a mass of feelers? (Relax: it’s otherwise quite cute, and only about 2cm long.) Its weird nose is sensitive: it gathers the same amount of information about what it touches, as a regular rodent’s eye gathers about what it sees. This makes the star-nosed mole the fastest hunter we know of, identifying and capturing prey (worms) in literally less than an eyeblink.

What can such a creature tell us about our own senses? A fair bit, actually. That nose is so sensitive, the mole’s visual cortex is used the process the information. It literally sees through its nose.

But that turns out not to be so very strange: Braille readers, for example, really do read through their fingertips, harnessing their visual cortex to the task. One veteran researcher, Paul Bach-y-Rita, has been building prosthetic eyes since the 1970s, using glorified pin-art machines to (literally) impress the visual world upon his volunteers’ backs, chests, even their tongues.

From touch to sound: in the course of learning about bats, I learned here that blind people have been using echolocation for years, especially when it rains (more auditory information, you see); researchers are only now getting a measure of their abilities.

How many senses are there that we might not have noticed? Over thirty, it seems, all served by dedicated receptors, and many of them elude our consciousness entirely. (We may even share the magnetic sense enjoyed by migrating birds! But don’t get too excited. Most mammals seem to have this sense. Your pet dog almost always pees with its head facing magnetic north.)

This embarrassment of riches leaves Higgins having to decide what to include and what to leave out. There’s a cracking chapter here on how animals sense time, and some exciting details about a sense of touch common to social mammals: one that responds specifically to cuddling.

On the other hand there’s very little about our extremely rare ability to smell what we eat while we eat it. This retronasal olfaction gives us a palate unrivalled in the animal kingdom, capable of discriminating between nearly two trillion savours: and ability which has all kinds of implications for memory and behaviour.

Is this a problem? Not at all. For all that it’s stuffed with entertaining oddities, Sentient is not a book about oddities, and Higgins’s argument, though colourful, is rigorous and focused. Over 400 exhilarating pages, she leads us to adopt an entirely unfamiliar way of thinking about the senses.

Because their mechanics are fascinating and to some degree reproduceable (the human eye is, mechanically speaking, very much like a camera) we grow up thinking of the senses as mechanical outputs.

Looking at our senses this way, however, is rather like studying fungi but only looking at the pretty fruiting bodies. The real magic of fungi is their networks. And the real magic of our senses is the more than 100 billion nerve cells in each human nervous system — greater, Higgins says, than the number of stars in the Milky Way.

And that vast complexity — adapting to reflect and organise the world, not just over evolutionary time but also over the course of an individual life — gives rise to all kinds of surprises. In some humans, the ability to see with sound. In vampire bats (who can sense the location of individual veins to sink their little fangs into), the ability to detect heat using receptors that in most other mammals are used to detect acute pain.

In De Anima, the ancient philosopher Aristotle really let the side down in listing just five senses. No one expects him to have spotted exotica like cuddlesomeness and where-to-face-when-you-pee. But what about pain? What about balance? What about proprioception?

Aristotle’s restrictive and mechanistic list left him, and generations after him, with little purchase on the subject. Insights have been hard to come by.

Aristotle himself took one look at the octopus and declared it stupid.

Let’s see him driving a car with eight legs.

Come on, Baggy, get with the beat!

Reading The Evolving Animal Orchestra: In search of what makes us musical by Henkjan Honing for New Scientist, 6 April 2019

The perception, if not the enjoyment, of musical cadences and of rhythm,” wrote Darwin in his 1871 book The Descent of Man, “is probably common to all animals.”

Henkjan Honing has tested this eminently reasonable idea, and in his book, The Evolving Animal Orchestra, he reports back. He details his disappointment, frustration and downright failure with such wit, humility and a love of the chase that any young person reading it will surely want to run away to become a cognitive scientist.

No culture has yet been found that doesn’t have music, and all music shares certain universal characteristics: melodies composed of seven or fewer discrete pitches; a regular beat; a limited sequence of rhythmic patterns. All this would suggest a biological basis for musicality.

A bird flies with regular beats of its wings. Animals walk with a particular rhythm. So you might expect beat perception to be present in everything that doesn’t want to falter when moving. But it isn’t. Honing describes experiments that demonstrate conclusively that we are the only primates with a sense of rhythm, possibly deriving from advanced beat perception.

Only strongly social animals, he writes, from songbirds and parrots to elephants and humans, have beat perception. What if musicality was acquired by all prosocial species through a process of convergent evolution? Like some other cognitive scientists, Honing now wonders whether language might derive from music, in a similar way to how reading uses much older neural structures that recognise contrast and sharp corners.

Honing must now test this exciting hypothesis. And if The Evolving Animal Orchestra is how he responds to disappointment, I can’t wait to see what he makes of success.