Book Review – Page 3 – Hoopoe

Book Review: Crossings: How Road Ecology Is Shaping the Future of Our Planet

***** An eye-opening and thought-provoking reportage

The road to hell might be paved with good intentions, but the roads to pretty much everywhere else are paved with the corpses of animals. In Crossings, environmental journalist Ben Goldfarb explores the outsized yet underappreciated impacts of the ~65 million kilometres of roads that hold the planet in a paved stranglehold. These extend beyond roadkill to numerous other insidious biological effects. The relatively young discipline of road ecology tries to gauge and mitigate them and sees biologists join forces with engineers and roadbuilders. This is a wide-ranging and eye-opening survey of the situation in the USA and various other countries.

As Goldfarb points out, roadkill is as old as the road but the phenomenon went into overdrive with the invention of the combustion engine and a new-found need for speed that menaced humans and animals alike. With the morbid curiosity typical of biologists, Dayton and Lilian Stoner published the first tally of motorcar casualties in 1925, in the process diagnosing “a malady with no name” (p. 16), as the word roadkill would not be coined for another two decades. The word road ecology was only coined in 1993 by Richard Forman, though it was translated from the German Straßenökologie that was coined in 1981 by Heinz Ellenberg.

As a discipline, road ecology both studies the impact of roads and formulates solutions. Particularly common, and featured extensively in this book, are wildlife crossings. Underpasses serve many animals but others have different needs such as overpasses or canopy rope bridges. Amphibians and reptiles are given a helping hand with toad tunnels and bucket brigades. Fish migration is being restored by retrofitting culverts that are better navigable.

An empty long, winding road running through trees going down a hill. — The long and winding road by Mussi Katz, via flickr.

To us, roads are the unnoticed connective tissue that links places of extraction with industry and commerce, and shuttles commuters between home and work. For other animals, they are barriers: despite the good intentions, wildlife crossings cannot serve all animals equally and cannot be constructed everywhere. Millions of animals still die in collisions every day. Goldfarb addresses the very real concerns of extirpation, habitat fragmentation, interrupted migrations, and noise pollution. With roads come humans who bring deforestation, hunting, real estate development, urban sprawl, tourism, etc.

Amidst this litany of harms, Goldfarb features several topics that will be eye-opening even to ecologists. There is the little-known history of how the US Forest Service constructed one of the world’s largest road networks of now mostly abandoned forest tracks. Roads also feed a diverse community of scavengers that includes humans; a necrobiome that “airbrushes our roadsides, camouflaging a crisis by devouring it” (p. 181). In Syracuse, Goldfarb faces the racist legacy of interstate highways that were bulldozed straight through Black and Latino neighbourhoods. Plans are now afoot to reverse this wrong, move the highway, and create a community where people can again walk to their destinations. In a brilliant flourish, Goldfarb connects this back to the book’s main topic: “Road ecologists and urban advocates are engaged in the same epic project: creating a world that’s amenable to feet” (p. 287).

Badbury Rings Avenue in Dorset showing a long downhill slope with large oak trees either side. — Badbury Rings Avenue – No HDR by JackPeasePhotography, via flickr.

So far, so good. Goldfarb’s writing shines and certain turns of phrase are memorable. I was initially concerned how US-centric this book would be. Though weighted towards US examples, Goldfarb also visits Wales, Costa Rica, Tasmania, and Brazil, and discusses several European initiatives.

Despite the gloomy picture, there are some encouraging signs. The US Forest Service has started decommissioning parts of its road network. Brazil, meanwhile, shows what government regulation can achieve. Here, highway operators are held legally responsible for dealing with the harm and costs resulting from collisions. Contrast this with the USA, Goldfarb observes sharply, where individual drivers are blamed for collisions. This “deflects culpability from the car companies building ever more massive SUVs and the engineers designing unsafe streets” (p. 295). As with addressing climate change, individual action only gets us so far; making roads safer demands systemic change, “a public works project, one of history’s most colossal” (p. 296).

And yet, something nagged at me. The focus on mitigation smacks of a palliative solution and Goldfarb concedes the limitations of road ecology. Crossings and fences will not stop the many other impacts of roads and risk becoming “a form of greenwashing […] a fig leaf that conceals and rationalizes destruction” (p. 265). As with other environmental problems, should we not first focus on abandoning or reducing certain behaviours, instead of turning to techno-fixes? Can we imagine something more radical? Can Goldfarb?

Tarmac country road running between two oil seed rape fields. — Country road and yellow field by Susanne Nilsson, via flickr.

To his credit, he admits wrestling with this problem. “The most straightforward solution to the road’s ills would be a collective rejection of automobility […] In the course of writing this book, I’ve felt, at times, like a defeatist—as though, by extolling wildlife passages, I foreclose the possibility of a more radical, carless future” (p. 295). I would have loved to see him explore this further in a dedicated chapter. Instead, Goldfarb comes down on the side of pragmatism. Bicycles and public transport are great for making urban areas more liveable, but most roadkill happens elsewhere. Furthermore, personal mobility is only part of the story, with logistics making up a huge chunk of traffic. The eye-opening chapter on Brazil, and the outsized influence of China’s Belt and Road Initiative that sees it invest in infrastructure globally, is a forceful reminder that the developmental juggernaut is nigh impossible to slow down. One road ecologist points out that you cannot seriously enter the discussion around roads if you oppose social and economic development, while another chimes in that, whether we like it or not, more roads will be built. Although I do not think resistance is futile, Goldfarb leaves me sympathetic to the road ecologists who are desperately trying to nudge construction projects in directions “that, if not quite “right,” are at least less wrong” (p. 270).

Goldfarb acknowledges the input of some 250 people and even then stresses his book is far from the final word on the subject. He encourages readers to take it as a starting point and read deeper, providing 43 pages of notes to the many sources of information he has used. I would additionally recommend A Clouded Leopard in the Middle of the Road by Australian road ecologist Darryl Jones which was published last year but seems to have flown under the radar compared to Goldfarb’s book. Overall, Crossings is a wide-ranging, eye-opening, and thought-provoking reportage that deserves top marks.

Book Review: The Last Days of the Dinosaurs

*****A unique on the story of dinosaur extinction and its aftermath

The day an asteroid slammed into the Yucatán Peninsula some 66 million years ago is a strong contender for “the worst day in history”. The K–Pg extinction ended the long evolutionary success story of the dinosaurs and a host of other creatures, and has lodged itself firmly in our collective imagination. But what happened next? The fact that a primate is tapping away at a keyboard writing this review gives you part of the answer. The rise of mammals was not a given, though, and the details have been hard to get by. Here, science writer Riley Black examines and imagines the aftermath of the extinction at various times post-impact. The Last Days of the Dinosaurs ends up being a fine piece of narrative non-fiction with thoughtful observations on the role of evolution in ecosystem recovery.

Before delving in, a brief word on what is not in the book. Black does not discuss the history of the research that discovered evidence of an asteroid impact, such as the iridium spike and the crater. Nor does she go into the ongoing debate on the relative contributions of the asteroid and Deccan Trap volcanism. Instead, Black’s approach is to imagine a day in the life of the survivors at various time points post-impact: after an hour, a day, a month, a year, a century, all the way up to one million years. She focuses on the Hell Creek formation in western North America as it offers one of the clearest windows into the mass extinction and its aftermath. Most chapters have a short coda that looks at how life was faring elsewhere on the planet. Black’s style of choice is narrative non-fiction: she is resurrecting individual animals and imagining their lives. As she explains in her preface, to allow full immersion, she is not interrupting the flow of her story with notes and references, which are found at the back of the book. An extensive, 58-page(!) chapter-by-chapter appendix reveals her process and discusses what we know, what is hypothetical, and where she has speculated to smooth over the gaps in our knowledge.

Barringer Crater in Arizona. — Barringer Crater by Simon Morris, via flickr.

Now, when this book was announced, just the prospect of dipping into the story of the disaster and the ensuing recovery already had me excited. However, The Last Days of the Dinosaurs surpassed even these expectations for two main reasons.

First, there are plenty of exciting new ideas and scientific findings here. Black’s interpretation of the impact will no doubt ruffle some feathers as it is particularly catastrophic. Forget the often-depicted idea of an asteroid seen streaking across the sky, Black writes, this thing came in fast at some 45,000 miles per hour (~20 km/s). Forget, too, the often-depicted drawn-out hunger winter for the surviving dinosaurs. I had not come across this idea before, but Black writes how a global heat pulse that lasted several hours fried anyone that could not crawl underground or stay submerged underwater. This is based on estimates of the amount of material ejected by the impact that, upon re-entry, heated the atmosphere to several hundreds of degrees centigrade. It would have ignited global wildfires. Finally, the impact injected vast amounts of sulfate aerosols into the atmosphere as the impact site was rich in calcium sulfate. The ensuing acid rain “might have effectively erased some of the slowly forming fossil record” (p. 256), explaining why fossils are hard to find in the layers around the K–Pg boundary.

Fossil of dinosaur jaw full of sharp teeth. — Fossil of dinosaur jaw full of sharp teeth by Ivan Radic, via flickr.

Regarding the survivors, Black has plenty of interesting ideas too. As seen at other times and other places, there was a fern spike. A rapid initial proliferation of ferns is frequently seen in devastated ecosystems where plants have died. And why did birds survive? One novel idea is that the survival of beaked, but not toothed birds is part of the answer. “Maintaining a mouth of sharp teeth comes with a reliance on animal food. […] A consumer that feeds on other consumers has very little to survive on now. But beaked birds do not face the same constraints” (p. 117). With the extinction of toothed birds and pterosaurs, the beaked birds were poised for an evolutionary radiation. Something similar happened with the mammals. Black prominently mentions the idea that Elsa Panciroli promoted in Beasts Before Us, that “it was competition between mammals that limited the number of different forms and niches Mesozoic mammals evolved into” (p. 158). With the extinction of more archaic mammaliaformes, the placental and marsupial mammals would flourish.

The second reason the book surpassed my expectations is Black’s reflections on the process of evolution and its role in ecological recovery. This is where her prose sings in places. One thousand years post-impact “[…] there is no script for what’s about to unfold, no cast of characters that inevitably must be filled” (p. 142). One million years post-impact a reptilian resurgence seems unlikely, but “the rise of the mammals is anything but assured […] When a global disaster ends one evolutionary dance, shifting the tempo, another begins, with no certainty as to who will lead” (p. 182). She poignantly notes how the fossil record “is not in any way a complete record of life on Earth. It is a record of fortuitous burials” (p. 254). And on the process of evolution, she writes how variation and happenstance provide “the raw material for natural selection and other evolutionary forces to shunt down different pathways. Not that there is any intent to this. It’s a passive state, a constantly running routine that is merely part of existence itself” (p. 196). This is music to my ears and Black’s writing is one of the highlights of this book.

Fossil of a dinosaur hand in a museum in sand. — Fossil of a dinosaur hand in a museum by Ivan Radic, via flickr.

Writing about such an iconic event carries the risk of intense scrutiny. No doubt, some experts and other palaeo-nerds will disagree with some of the details presented here. I think her appendix is sufficiently explicit about where she speculates and where she has chosen not to hedge her bets on different explanations. I was willing to read the book in this spirit, as one possible interpretation of how things might have unfolded, though one that Black carefully backs up with scientific evidence. My quibbles are rather minor instead. One is that the book has no index, the other is that there are no notes to the appendix. Relegating the discussion of the underlying science to the appendix is a defensible choice. But not properly referencing the studies mentioned here is, to me, a minor blemish on an otherwise excellent book.

If you have any interest whatsoever in dinosaurs and their extinction, this book comes highly recommended. Her take on the topic, dipping into the extinction and recovery at various moments post-impact, is novel. I am not familiar with other books attempting this. As a bonus, I expect that many readers will come away with a better understanding of the process of evolution.

The Last Days of the Dinosaurs is available from our online bookstore.

Book Review: Dinosaur Behaviour

**** Handsomely illustrated and accessible

Reconstructing how dinosaurs behaved from just their fossilised bones might seem like science fiction but is very much science fact. In Dinosaur Behavior: An Illustrated Guide, veteran palaeontology professor Michael J. Benton joins forces with palaeoartist Bob Nicholls to do what it says on the tin: write a richly illustrated introductory book on dinosaur behaviour that is well-suited for novices.

In Dinosaur Behaviour, Benton takes the reader through five main topics: physiology (which sets the pace for everything else), locomotion, senses and intelligence, feeding, and social behaviour (which includes courtship, reproduction, parental care, and communication). One or several ‘forensics’ boxes in each chapter introduce the basic gist of certain methods.

Reading through this book, it becomes abundantly clear that our understanding of dinosaur behaviour relies on two approaches. Though Benton does not mention it as explicitly as in his previous book The Dinosaurs Rediscovered, the first of these is new high-tech toys and tools. Examples include computed tomography (CT) scanners, normally used in hospitals, to make detailed X-ray scans of fossilised brains (so-called endocasts) and so determine brain anatomy. Or finite element analysis normally used in engineering to model forces and stresses on jaws and teeth and so determine e.g. bite force. The second approach is ‘old-fashioned’ comparative anatomy and ethology: it pays to have a good knowledge of natural history when you are a palaeontologist. One example is the histological study of fossil dinosaur bones. Cutting thin bone sections and examining these under a microscope shows that some dinosaurs closely resemble mammals and birds, supporting the idea that smaller species were endotherms (‘warm-blooded’, i.e. generating their own body heat). Or take the microscopic study of melanosomes (pigment-containing organelles) in fossil feathers to determine colour in life. A final example is the comparison of footprints made by modern running birds with fossil tracks to determine things such as gait and running speed.

If you are well-versed in (popular) palaeontology, much of what is presented here will be familiar. Even so, I picked up interesting titbits. One example is a recent study of Psittacosaurus that describes a cloaca, the multipurpose orifice also seen in birds where the digestive, urinary, and reproductive tracts all open to the outside world. This suggests that dinosaur sex, for at least some species, was a matter of the appropriately named ‘cloacal kiss’ rather than the brandishing of reptilian genitals. Other insights fell into the embarrassing ‘I should have known this’ category. We tend to think of walking on two legs as something advanced because our mammalian ancestors walked on all fours, but for dinosaurs, it was the reverse; they started out bipedal and quadrupedality only evolved later in e.g. the large sauropods. Particularly interesting is the study by Kat Schroeder and colleagues who looked at fossil communities of theropods and noticed a so-called carnivore gap: there is a lack of medium-sized ones in the fossil record, even though there are medium-sized herbivores. One explanation could be that dinosaur eggs had an upper size limit, meaning that young carnivores hatched small and had an awful lot of growing to do. As they did, ‘they passed through a whole range of feeding modes, each step along the way acting like a different species’ (p. 137), effectively plugging the ecological niche of medium-sized carnivores.

Despite the broad range of topics, there are some curious omissions. The chapter on feeding e.g. discusses jaws, teeth, and the use of isotopes to determine diet, but not microwear analysis of teeth. What I found most surprising is that Benton does not introduce the concept of trace fossils or ichnology, their study. Yet, examples such as trackways (some possibly showing long-distance migrations), coprolites (fossil poop), and nests are all discussed here. Another surprising omission is that the two-page bibliography does not include most studies mentioned in the text, even though it references other technical articles.

Dinosaur Behavior is mostly very suitable for readers with little to no background in palaeontology. Benton explains even basic terminology (physiology, cannibalism) as he goes, though there is the occasional curveball. One example is the morphospace diagram showing a principal component analysis on page 131, which, I hope those with a background in statistics will agree, is a rather abstract way of visualizing data that requires a bit more explanation than is given here. Though the book is published by Princeton University Press, it has been produced by UniPress Books who can be considered the spiritual successor to popular science publisher Ivy Press. What this means is that information is accessibly presented in bite-sized sections on one or several page spreads, with long sections further divided using subheadings. The downside is that this restricts how thoroughly topics can be explored. Leafing through e.g. Naish & Barrett’s Dinosaurs: How They Lived and Evolved shows more nuance in its chapter on behaviour.

Finally, I have to mention the excellent colour and black-and-white artwork by Bob Nicholls that livens up the text. I loved the drawing of courtship in Confusiusornis on pages 168–169. Despite the overlap in topic, this is all-new artwork compared to Locked in Time. Other diagrams have all been carefully designed or redrawn, using colours where appropriate. The only design element that did not work for me was the choice of sans-serif font which made e.g. the letters ‘a’ and ‘o’ hard to tell apart.

Serious palaeontology buffs might find the contents here somewhat superficial, but overall, this is a handsomely illustrated book that offers an accessible introduction suitable for novices and possibly even curious high-school pupils. It would also make for a great gift.

Dinosaur Behaviour: An Illustrated Guide is available from our online bookstore.

Book Review: Blue Machine

***** An engrossing odyssey into oceanography

In a break from many other books about the deep sea that talk about animals, Blue Machine focuses on the ocean itself, revealing a fascinating planetary engine. Equal parts physical oceanography, marine biology, and science history, topped off with human-interest stories, Czerski has written a captivating book that oozes lyricism in places.

Czerski is an accidental oceanographer, stumbling into the discipline from a background in physics. She boasts a long list of science communication credentials as a TV presenter, podcast host, columnist, public speaker, and author. This is a big book with chunky chapters but Czerski keeps the flow going by alternating between scientific explanations, fascinating experiments, and remarkable historical episodes. I find the deep sea endlessly fascinating and have been drawn ever further into oceanography through my reviews, yet something was always missing. This book has finally scratched the oceanographic itch I have long been trying to satisfy. How so, you might ask?

Stormy sea and waves crashing against a stony beach. — Stormy Waters IMG_6958 by Ronnie Robertson, via flickr.

Start with that introduction. If you zoom right out, what sets a planet’s temperature, and with it the potential for life, is the balance between energy input from the sun and energy loss to the universe in the form of heat. From this grand, cosmic perspective, what the ocean with its circulating currents does is intercept some of that incoming energy and prevent it from immediately escaping again, instead “diverting it on to a much slower path through the mechanisms of the Earth: ocean, atmosphere, ice, life and rocks” (p. 5). From an energy point of view, “the Earth is just a cascade of diversions, unable to stop the flood but tapping into it as it trickles past; and the ocean is an engine for converting sunlight into movement and life and complexity, before the universe reclaims the loan” (p. 6). To me, this was such an awe-inspiring, attention-grabbing perspective on life on Earth, expressed so eloquently, that I wondered: is Czerski the new Ed Yong of oceanography? Tell me more, please!

What helps to understand the above perspective is the fact that the ocean is a vast three-dimensional environment that is constantly in motion, creating and maintaining differences at different scales. Heat and salinity create different layers of water that do not readily mix, meaning the ocean is stratified. This results in gigantic underwater conveyor belts and waterfalls. What makes these processes interesting is the shape of the container holding all this water: i.e. the continents and underwater topography. The local gravitational pull of the underlying rocks deforms the water surface, creating domes and holes over very large surface areas, a shape known as the geoid. Many more fundamental features and principles are described though she admits that she cannot squeeze the full complexity of the ocean into one book, treating other topics only briefly or not at all.

Bright blue, large wave tubing with splashes all around it. — The tube by Misty, via flickr.

Admirably, Czerski is equally at home in the marine biology department and she features some wonderful critters here. True, these abound in all good popular science books about the deep sea, but her physics background allows her to show how the physical and biological worlds intertwine. A beautiful example of this is the mesoscale eddies that are spun off by oceanic gyres: large islands of rotating water that become temporary havens for all the plankton and fish that find themselves inside. The formation of these wandering buffets is such a regular phenomenon that large ocean predators such as tuna can make a living by roaming the seas in search of them.

Another captivating element is the many ingenious experiments, both historical and current, that she describes here. We almost developed a method to collect a long-term dataset on the global ocean’s temperature by bouncing sound waves through the seas, but the idea stalled after a successful pilot experiment in 1991. More successful is the Continuous Plankton Recorder Survey which has been running for the last 90 years, deploying mechanical recorders towed behind ships that use elegant internal clockwork to capture plankton on long strips of mesh and have gathered valuable long-term records.

The physical world also entwines with human history. One example is the narrow northern half of the Indian Ocean where gyres do not form but seasonal currents flow eastwards and westwards. The 14th-century Chinese Ming Dynasty used these to send expeditions of large ships laden with valuables up and down the coast of Asia and Arabia, trading goods for political influence and prestige. I was similarly captivated by the poorly known story of the 18th-century Scottish herring lassies: bands of female contractors who travelled south along the English coast each summer, following the southwards moving herring fleet. While the men worked the boats out at sea, the women were ready in ports and at beaches to gut, salt, and pack each day’s landing before the freshly-caught fish could spoil. Hard-working, skilled, and independent, they were decades ahead of most other women in Victorian England.

Wave Breaking on rocks at Asilomer State Beach. — Wave Breaking Asilomer State Beach by Charlie Day, via flickr.

All of this is backed up by an attitude that, coming from a scientist, is refreshingly clued in to social issues. This becomes explicit in the final chapter where she addresses the environmental issues she has so far avoided. Though a popular mantra in politics is that we need to follow the science, she opposes this “for the simple reason that science does not lead. Where leadership comes from is a clear statement of values” (p. 381). Science can inform these, yes, but we have to decide what we care about for ourselves and our communities. Going down this path involves hard questions without simple answers, and nuance rather than binary “I am right, you are wrong” categories. It also means breaking with our perception of “the ocean as the end of a one-way pipe” (p. 289). There is no “away” on this planet for our trash. And it means breaking with a culture of infinite growth on a finite planet. Her thinking here is influenced by her contact with Polynesian cultures that value cooperation, openness, and teamwork, in contrast to the Western mindset of ownership and power play.

If I need to sound a critical note it is the lack of illustrations. Though the UK version features nice endpapers and a stunning cover, there are only two maps and two illustrations in the rest of the book. Especially some of the physical oceanography principles would have benefited from explanatory diagrams.

Blue Machine is an engrossing odyssey into oceanography. Czerski brings her substantial experience in science communication to bear on this topic and has written a transformative book. She brings to life the watery fabric of the ocean itself in ways I have not encountered before.

Book review: The Mind of a Bee

***** Fascinating and information dense
Leon Vlieger, NHBS Catalogue Editor

It is tough being a social insect. When people are not trying to exterminate you, they might marvel at the collectives you form, but does anybody think much of you, the individual? Leave it to Lars Chittka, a professor in sensory and behavioural ecology, to change your views. The Mind of a Bee is a richly illustrated, information-dense book that explores a large body of scientific research, both old and new.

Chittka is very focused in his approach and The Mind of a Bee effectively summarises a large number of experimental studies in narrative form, with very few diversions. He cleverly avoids overheating your brain by having chapters flow logically into each other, but especially by dividing each chapter into short, headed sections. Each of these takes a particular question and discusses a few relevant studies in anywhere from one-half to three pages. Some of these are his own work but he ranges far and wide and includes both classic and recent research. The book is furthermore illustrated with numerous diagrams and photos that helpfully clarify experimental protocols and results. Honey bees are unsurprisingly the most intensively studied but Chittka discusses informative studies across a range of bee species and sometimes other insects as well. The book roughly covers three biological disciplines: sensory and neurobiology, ethology, and psychology.

Justifiably, the book opens with sensory biology. Before we understand what is in the mind of any organism, Chittka argues, we first need to understand the gateways, the sense organs, through which information from the outside world is filtered. These are shaped by both evolutionary history and daily life (i.e. what information matters on a day-to-day basis and what can be safely ignored). Chapter 2 deals with the historical research that showed that bees do have colour vision and furthermore can perceive ultraviolet (UV) light. Chapter 3 bundles together research on numerous other senses, including ones familiar (smell, taste, and hearing) and unfamiliar to us (perception of polarised light, Earth’s magnetic field, and electric fields). The antennae of bees, in particular, are marvels; Chittka likens them to a biological Swiss army knife, packing numerous different sense organs into two small appendages. Tightly connected to sensory biology is how this incoming information is processed in the brain, though Chittka postpones discussing neurobiology to chapter 9. He describes the discovery and function of different brain areas and highlights the work of Frederick Kenyon who would inspire the better-remembered Santiago Ramón y Cajal. Thanks to them, we now understand that brains consist of numerous specialised nerve cells. Though the bee brain is small, Chittka argues that size is a poor predictor of cognitive skills; it is the wiring of neurons that matters. Rather than be surprised that small-brained insects such as bees can do so many clever things, Chittka instead tickles the reader with the opposite question: “Why does any animal need as large a brain as a bee’s?” (p. 153).

What clever things do bees do, you ask? That is the subject of the preceding five chapters where Chittka surveys a large body of behavioural research. Honey bees are famous for their waggle dance by which they communicate the location of flowers but also, this was news to me, the location of potential nest sites when the swarm relocates. But Chittka discusses more, much more: how bees navigate space using landmarks, show a rudimentary form of counting, solve the travelling salesman problem, learn to extract nectar from complex flowers, learn when to exploit certain flowers (and when to ignore them), and learn new tricks by observing other bees. But what about instinct, something most behaviours were traditionally ascribed to? He has some insightful comments on this: “even the most elemental behavior routines need to be refined by learning: instinct provides little more than a rough template” (p. 50). What really made me fall off my chair is that bees have long been outsmarting researchers in choice experiments. Many behavioural experiments take the form of choice tests, where bees need to pick between two locations or objects that differ in e.g. colour or shape with one option containing a sugary solution as a reward. Bumblebees would simply be lazy and check out both options in random order. Until, that is, protocols were modified by adding a bitter-tasting solution to the wrong choice as a penalty.

The final two chapters explore bee psychology. One chapter shows how, in a hive full of bees, the members are not anonymous and interchangeable. Rather, they show individual differences in e.g. their preferred order in which to visit flowers during foraging or how fast they learn to solve problems. The final chapter makes the case that bees have a form of consciousness, though Chittka clarifies he is not arguing it is as rich and detailed as that of humans. That said, they show a slew of behaviours that scientists will label as evidence for consciousness when exhibited by bigger-brained vertebrates. Chittka is happy to play devil’s advocate: sure, theoretically, all the behaviours described in this book could be replicated by an unconscious algorithm. However, the required list of specific instructions is growing long and, increasingly, the more likely answer seems to be that bees possess “a consciousness-based general intelligence system” (p. 208).

As mentioned above, this book is focused. If you enjoy reading about the facts and the study system with minimal (autobiographical) diversions, Chittka has got you covered. The only digression he allows himself is to include biographical details of older generations of scientists. This includes inspiring tales such as Karl von Frisch who described the honey bee waggle dance and later barely escaped being dismissed from his post by the Nazis. And look out for repeat appearances of Charles Turner, a now largely forgotten African American scientist who published pioneering work despite having been denied a professorship based on his ethnicity. But there are also tragic stories such as Kenyon’s, who snapped under pressure of not securing a permanent job and was incarcerated in a lunatic asylum where he died more than 40 years later, alone and forgotten. Chittka includes occasional quotations from historical literature to show that “many seemingly contemporary ideas about the minds of bees had already been expressed, in some form, over a century ago” (p. 15).

The Mind of a Bee makes for fascinating reading, convincingly showing that bees are anything but little automatons. The tight structure and numerous illustrations make it accessible, though be prepared for an information-dense book.

Book review: The Rise and Reign of the Mammals

***** Epic in scope and majestic in execution
Leon Vlieger, NHBS Catalogue Editor

Imagine being a successful dinosaur palaeontologist and landing a professorship before you are 40, authoring a leading dinosaur textbook and a New York Times bestseller on dinosaurs. Imagine achieving all that and then saying: “You know what really floats my boat? Mammals.” After the runaway success of his 2018 book The Rise and Fall of the Dinosaurs, palaeontologist Stephen Brusatte shifted his attention and now presents you with the follow-up, The Rise and Reign of the Mammals. Taking in the full sweep of mammal evolution from the late Carboniferous to today, this book is as epic in scope as it is majestic in execution.

Mammals shared our planet with the dinosaurs throughout their long reign, from the initial split of our amniote common ancestor into synapsids (us) and diapsids (them), to their extinction at the end of the Cretaceous. Over the course of some 100 million years, a parade of lineages evolved—archaic mammals all—piecemeal developing the traits we recognise as mammalian today: pelycosaurs, therapsids, cynodonts, mammaliaformes, docodonts and gliding haramiyidans, multituberculates, and therians who gave rise to today’s placentals, marsupials, and monotremes. However, the above must not be mistaken for a linear march of progress. “[M]ammals were a still unrealised concept, which evolution had yet to assemble” (p. 20). Simultaneously, it does not behove us to call these now-extinct groups evolutionary dead ends. “In their time and place, these mammals were anything but obsolete” (p. 88).

With the extinction of the dinosaurs, the rise of mammals turned into a reign. Isolated on various land masses after the supercontinent Pangaea had fragmented, they were poised for a slow-motion taxonomic starburst that would play out over the next 66 million years. In the northern hemisphere, placental mammals replaced multituberculates and metatherians and rapidly evolved into primates and the odd- and even-toed ungulates. The latter two evolved giants: brontotheres, chalicotheres, and cetaceans.

Brusatte’s strength is to bring to life the above flurry of names. What kind of creatures were they? And how can we deduce this from fossil evidence? Somewhere between chapters 6 and 7, I became awestruck by his narrative as the enormity of the mammalian evolutionary trajectory started to come into full view: bats, elephants, South American native ungulates (origins: uncertain), metatherians migrating to Australia and spawning a spectacular marsupial radiation, grazers diversified as grasses went global, and somewhere at the end, hominins evolving and repeatedly spilling out of Africa, contributing significantly to recent megafauna extinction. What a wild ride!

The macroevolutionary story is fascinating in itself, yet Brusatte makes it even better with some interesting observations of his own. We usually think of the dinosaurs as dominating the mammals, but, he suggests, this went two ways: “While it is true that dinosaurs kept mammals from getting big, mammals did the opposite, which was equally impressive: they kept dinosaurs from becoming small” (p. 95). Furthermore, DNA studies suggest that many modern mammal lineages originated back in the Cretaceous. But where are the fossils? Could some of the poorly understood archaic placentals such as condylarchs, taeniodonts, and pantodonts be the missing fossils that we have not yet been able to link to modern groups because of the lack of signature anatomical features? Excitingly, Brusatte is part of a research consortium that is building a master family tree based on both anatomy and DNA.

As in his last book, Brusatte excels at explaining complex research methods and scientific concepts. One example is Tom Kemp’s concept of correlated progression. Several times during early mammal evolution, a whole suite of anatomical, behavioural, and functional traits were changing together, making it hard to unravel what was driving what. For instance when cynodonts shrunk in size and changed their growth, metabolism, diet, and feeding styles. Then there is the revision of the mammal family tree based on DNA sequencing. The classic tree, championed by zoologist George Gaylord Simpson in 1945, was based on anatomical features. By the early 2000s, DNA-based genealogies suggested that many supposed relationships were actually cases of convergent evolution, resulting in a new classification that reflected geographical patterns rather than anatomy. The new groupings came with some tongue-twisting names: Afrotheria, Xenarthra, Laurasiatheria, and Eurarchontoglires. A final example is tooth morphology, an important diagnostic trait in this story.

What helps with these explanations are some excellent illustrations. B/w photos show amazing fossils, Todd Marshall contributes both decorative chapter headings and explanatory artwork, and Brusatte’s former student Sarah Shelley adds b/w diagrams, illustrating for instance the remarkable changes in jaw bones and how some of these were repurposed to become our inner ear bones! Woven throughout are stories of the people behind the research. Brusatte introduces both young scientists and many past scientists that are not widely known.

In what is surely a hallmark of his love and enthusiasm for the field, Brusatte’s bibliography has again been written as a narrative. It is like a chatty literature review in which he recommends books and papers, indicates where literature has become outdated, adds more technical details or clarifications, discusses where there is active debate and disagreement, and shortly touches on topics that he had to omit from the main narrative. Yes, this takes up more space than a regular reference section, and I am sure it is more time-consuming to write, but it is ever so useful. You could not wish for a better starting point if you wanted to read deeper into the technical literature.

Finally, you might be left wondering how this book compares to Elsa Panciroli’s Beasts Before Us which covered early mammal evolution up to the K–Pg extinction. There is overlap here in more than one way; Brusatte co-supervised her PhD project describing the docodont Borealestes from a Scottish fossil. I was therefore mildly surprised that he does not mention her book. There is some inevitable overlap as both books walk through the same groups, though Brusatte provides a fuller picture by covering mammal evolution up to today. Panciroli’s book stands out for its fantastic writing, though, so you cannot go wrong by reading them both.

The Rise and Reign of the Mammals is a more-than-worthy successor to The Rise and Fall of the Dinosaurs. Brusatte convincingly shows that the evolutionary story of mammals is just as fascinating—if not more so—as that of the dinosaurs.

Book review: What an Owl Knows

***** A hoot of a book
Leon Vlieger, NHBS Catalogue Editor

Owls are one of the most enigmatic groups of raptors, in part because there is so much we still do not understand about them compared to other birds. Nature writer Jennifer Ackerman previously wrote the critically acclaimed The Genius of Birds. In What an Owl Knows, she reveals the creature that hides under that puffy exterior, peeling back the feathers layer by layer to show our current scientific understanding of owls. She has interviewed scores of scientists and owl aficionados as part of her background research, making this as much a book about owls as about the people who study and love them. A captivating and in places touching science narrative, this book is a hoot from beginning to end.

Owls are everywhere in the human imagination and, Ackerman argues, have always been: “We evolved in their presence; lived for tens of thousands of years elbow to wing in the same woods, open lands, caves, and rock shelters; came into our own self-awareness surrounded by them; and wove them into our stories and art” (p. 235). For all that, their nocturnal lifestyle makes them hard to study and they have long been—and in many places still are—wrapped in superstition. Ackerman dedicates a chapter to such beliefs and the harms that frequently flow from them. Fortunately, the tide is turning. Thanks to the tireless efforts of a dedicated cadre of scientists, conservationists, and numerous volunteers, a far more fascinating creature emerges from the contradictory tangle of ideas that humans have held about owls.

A red thread that has been subtly woven through this book is the importance of understanding animals on their terms. Ed Yong’s An Immense World is one recent example of this welcome trend amongst science writers and Ackerman appropriately starts with a chapter on owl sensory biology. What is it like to be an owl? Though this question can never be fully answered, that should not stop us from trying our hardest. Vision and hearing are obviously important to owls but the book has plenty of surprises up its sleeve once you start digging into the details: from the magnificent facial disk that acts somewhat like a parabolic reflector to gather sound, a hearing system that does not seem to age, to the fact that owls can see ultraviolet light. At night. With rod rather than cone cells (like pretty much every other bird).

The same question motivates research on owl vocalisations as “a hoot is not just a hoot” (p. 81). Owls utter a profusion of yaps, squawks and warbles and Ackerman paints a lively portrait in words. Barn owls have “a raspy hiss that sounds like a fan belt going out on your car” (p. 82), while the tiny Flammulated Owl breaks the link between body size and vocal pitch, sounding like “a big bird trapped in a small body” (p. 82, quoting ornithologist Brian Linkhart). These sounds can reveal an awful lot about the individual owl and its relationship with other owls in the landscape. Ackerman criticises some of the research on owl intelligence. They cannot pass the string-pulling test, a common test in ethological research in which an animal has to pull on a rope to reel in food that is out of reach. The idea is that it tests an animal’s understanding of cause and effect. But is this a fair test or does it “point to the limitations of our definitions and measures of intelligence” (p. 261)?

The most intimate insights have come from rescued owls that can no longer be returned to the wild. Many researchers have ended up caring for an individual and becoming intimately familiar with them. Gail Buhl, a leading authority on training rehabilitated captive owls, here explains five important things that she has learned. One particularly poignant observation is that owls might appear calm and stoic around humans, but having paid close attention to their body language, Buhl concludes that “they’re experiencing the same stress as other raptors, but they’re internalising it” (p. 228). This has major consequences for how even well-intended trainers and rehabbers ought to behave around owls. “We need to treat them not as mini-humans in feathers, but as their own entity” (p. 231), Ackerman writes, before throwing in a beautiful quote from naturalist Henry Beston. In his words, wild animals “are not brethren, they are not underlings; they are other nations, caught with ourselves in the net of life and time” (pp. 231–232).

Following on directly from her last book on bird behaviour, there are fascinating chapters here on the behaviour of owls: their courtship and breeding, their parental behaviour, their roosting, and their migration. Yes, many owls are migratory and some species can cover surprising distances. Ackerman makes a fantastic case for the value of long-term monitoring programmes to establish reliable population estimates. This is vital data for conservation efforts and is often missing. And sometimes what we think we know is wrong, as in the case of the Snowy Owl. Where initial estimates put the global population at some 200,000 birds, satellite tracking has revealed that they are actually a single population moving around the whole Arctic Circle, resulting in duplicate counts. Revised estimates now put the figure at a mere 30,000 birds.

Ackerman relies on the input of numerous scientists and volunteers. As such, this is as much a book about the people who study owls. I was delighted to hear more from Jonathan Slaght (his book Owls of the Eastern Ice is magnificent). Other stories tug on the heartstrings and none more so than that of Marjon Savelsberg. A Dutch musician trained in baroque music, her dreams came crashing down when she was diagnosed with a heart condition that consigned her to a mobility scooter. When she stumbled on the website of the Dutch Little Owl Working Group, she quickly became one of their most active volunteers, revealing a skilled ear for analysing owl calls. Suddenly, she had a new career and a new group of appreciative ecologist colleagues: “[I] realised I was still a musician. All the skills that I learned, all the talent I have, I can still use, just in a different way” (p. 105). It is a powerful story of redemption-by-owl.

Ackerman carefully balances these two facets: the scientific insights that she has carefully distilled from research papers and interviews, and the personal stories of those who study and love owls. As a result, What an Owl Knows is compulsively readable and readily accessible for those who lack a scientific background in ornithology.

You might also be interested in reading our Q&A with Jennifer Ackerman in which we discuss owls’ reputation for wisdom, the incredible research that is shedding more light on their lives, and the mysteries that still remain.

Book review: Otherlands

***** A spine-tingling debut
Leon Vlieger, NHBS Catalogue Editor

Our planet has been many different worlds over its 4.5-billion-year history. Imagining what they were like is hard – with our limited lifespan, deep time eludes us by its very nature. Otherlands, the debut of Scottish palaeontologist Thomas Halliday, presents you with a series of past worlds. Though this is a non-fiction book thoroughly grounded in fact, it is the quality of the narrative that stands out. Beyond imaginative metaphors to describe extinct lifeforms, some of his reflections on deep time, taxonomy, and evolution are simply spine-tingling.

The 16 chapters in Otherlands, each accompanied by a gorgeous illustration from Beth Zaiken, step back in time by millions or even tens of millions of years to visit a place on Earth and describe its ecosystems and organisms. Halliday includes well-known sites such as end-Cretaceous Hell Creek (66 million years ago, or mya) or Lagerstätten such as the Cambrian Chengjiang biota in China (520 mya). Far more interesting are the little-known eras and places such as the Italian promontory of Gargano during the Miocene Messinian Salinity Crisis (5.3 mya), the sweltering warmth of Seymour Island in Antarctica during the Palaeocene-Eocene Thermal Maximum (41 mya), or the underwater life around the Silurian Yaman-Kasy vent in Russia (435 mya).

Stylistically, Otherlands is a narrative non-fiction book. What that means is that, though everything is grounded in fact, Halliday does not get lost in the details. Where competing hypotheses exist he picks one and runs with it, rather than detailing the academic debates and different schools of thought. It is a stylistic choice that I can get behind given the quality of the writing that follows.

Because make no mistake, Halliday knows how to craft captivating prose. He won the Hugh Miller Writing Competition in 2018 and the John C. Marsden Medal from the Linnean Society for the best doctoral thesis in biology in 2016. Reading Otherlands, it is easy to see why. I do not know what they feed Scottish palaeontologists, but I was reminded of Elsa Panciroli’s Beasts Before Us. Let me back up my enthusiasm with some quotes that can only touch on a fraction of what is on offer.

There are the obvious imaginative metaphors to describe animals. The Triassic gliding reptile Sharovipteryx mirabilis (225 mya) is imagined looking rather inelegant once landed “with its membrane retracting and limbs thrown all directions like a collapsing deckchair” (p. 159), while the Ediacaran sedentary animal Dorothy’s Rope (550 mya) resembles upright towers “composed of bulges like knotted rope, as if Gaudi had designed an industrial town” (p. 277). Other descriptions are more poetic. Basilosaurids, the first fully aquatic whale ancestors in the Eocene (41 mya), have yet to evolve the melon organ. They “can listen to the music of the oceans, but they have not yet learned to sing” (p. 86).

Particularly powerful are his reflections on deep time. A recurrent theme in this book is that of impermanence: “gatherings of species in time and space may give the illusion of stability, but these communities can only last as long as the conditions that help to create them persist” (p. 18). Some ecosystems never return. The long-lived Jurassic crinoid colonies (155 mya) that made a home on floating logs blown into the sea during storms disappeared when the evolution of shipworms made “this way of life impossible, something that can and will never be replicated in quite the same way again; wood just doesn’t float for as long as it used to” (p. 151). And while the world feels old in our day, it is easy to forget the world was already old in the deep past. The mountains of the Triassic (225 mya) “are built from the deep sea”, within which can be seen “the coils and shapes of the long-extinct creatures of the Carboniferous seas, well over 100 million years old even now” (p. 158).

What made my hair stand on end were Halliday’s reflections on phylogenetics, the evolutionary relationships between animals. I love how he drowns scientific concepts in poetic language. Take the Paleocene Baioconodon (66 mya). Beyond one of the earliest placental mammals, we do not really know what it was. “Their anatomy is too non-committal, too similar to and yet too distinct from too many living orders to be placed with confidence. […] They are an unspecialised, Platonic placental, a lump of living clay from which all others are stretched, pinched and pulled into shape” (p. 105). We cannot even describe its young as kits or calves: “it does not yet make sense to talk of cattle or dogs, of monkeys or horses. None of these groups exist yet […] names lose tangibility in the depths of the past, and our language has no description for the young of common ancestors” (p. 104). You start to see why Halliday wrote his way backwards from the present. He makes a similar observation about the Ediacaran biota. Alien to us, “they are aberrant only from a modern perspective” (p. 282). Our confusion is partially because “we are trying to define them the only way we can: on the basis of those few survivors to have found paths to the present”, while the dead-end branches “by the simple fact of having not survived, forfeit a common name” (p. 283).

Similarly spine-tingling are his explanations of evolutionary processes. Species names are artificial designations for a continuous phenomenon. The way palaeontologists deal with this can be compared to rivers. Just as a river can split and its two branches be called by two names from that point in space forward, so can a species that spatially separates be called by two names from that point in time forward. And why did so many higher taxa appear during the Cambrian explosion? One idea is that, once in place, fundamentals cannot be changed easily: “evolution today can only be played within the constraints set by the past”. Another idea is that “there is nothing intrinsically impossible about a new body plan developing today, were it not for the existence of others”. Gould wrote of filling the ecological barrel and Halliday puts it thus: “establishing the basic roles within an ecosystem is like adding large rocks into a barrel […] evolutionary processes […] adding in finer and finer divisions of ecological processes, pebbles and sand falling into the barrel between the gaps left by the larger stones, structures built on other structures” (p. 258). Not only does this ring true, but it is also truly beautiful language.

Otherlands is an exceptional debut that can be savoured like a fine wine. I found myself reciting passages to anyone within earshot. Beyond a fascinating tour of extinct lifeforms, Halliday’s carefully crafted yet poetic descriptions of scientific concepts are a masterclass in spellbinding science communication.

You might also be interested in our Q&A with Otherlands author Thomas Halliday where we discuss the book and the process of writing it, our endless fascination with dinosaurs and the lessons we might learn from studies of deep time.