Evolution is often characterised rather one-sidedly in terms of a struggle for existence, “red in tooth and claw”, and selfish genes. And yet, as evolutionary biologist Jonathan Silvertown shows here, cooperation in biology is both widespread and ancient. In his entertaining Dinner with Darwin which I reviewed way back in 2018, he briefly touched on food sharing in humans as one example of cooperation; in Selfish Genes to Social Beings, he gives the topic at large the book-length treatment it deserves. Silvertown here writes for a broad audience, explicitly including those without a formal background in biology. With nary an equation in sight, he relies on a potent combination of human-interest stories, wit, and ingenious metaphors to convince you that cooperation is an important component driving evolution.

Selfish Genes to Social Beings: A Cooperative History of Life, written by Jonathan Silvertown, published by Oxford University Press in April 2024 (hardback, 288 pages)

Cooperation initially flummoxed biologists, yet, Silvertown contends, a few straightforward conditions are sufficient for its appearance. I might just as well hit you over the head with his take-home messages now. Two conditions are required for cooperation to evolve. First, the benefits to the individuals involved have to outweigh the costs. Attentive biologists might immediately pipe up that that simple statement hides important technicalities, while others will undoubtedly exclaim: “Yes, but what about…?— bear with me, I will get to this. Second, there has to be a way for cheaters to be detected and excluded, or otherwise. the system will buckle under their exploitation.

Silvertown tackles his subject in 16 chapters that are divided over four parts, working his way down from groups to individuals, to cells, to genes. This approach has two advantages. First, it allows him to open the book with human interest stories that reel you in. Take the often-ignored aspect of trench warfare in World War I, particularly the numerous smaller skirmishes that saw infantry on both sides communicate and cooperate to minimise casualties in a live-and-let-live honour system. It was artillery and high command, both operating at a distance, that undermined these attempts and created the horrors for which this war is remembered. Or take the remarkable cooperation on , where the captain was democratically elected, the ship was owned by the whole crew, and plunder was shared^[1].

“A personal lightbulb moment was the insight that bacteria may be single-celled, but they are not solitary; there is a lot of communication happening.”

The second advantage of starting at the level of groups and individuals is that the examples speak to your everyday experience. It is relatively easy to imagine what sociality in insects, such as honeybees, or cooperative breeding in birds looks like. Somewhat less familiar are lichens, symbiotic organisms composed of a fungus and an algae or a cyanobacterium. I did not appreciate just how fascinating lichen biology is. Take the fact that this symbiosis has evolved numerous times independently and that different species are at different points along the continuum of becoming partially to fully integrated organisms. As the book progresses down to cells and genes, the subject matter becomes more complicated and abstract, but by then you will have internalized some of the logic. A personal lightbulb moment was the insight that bacteria may be single-celled, but they are not solitary; there is a lot of communication happening. Quorum sensing allows bacteria to check that a sufficient number of cooperators are present before secreting so-called public-good molecules. These include digestive enzymes (bacteria digest externally and absorb the resultant broth), or sticky substances that form a protective biofilm. Similarly fascinating are transposons, the mobile genetic elements that move around within and between individuals and species. They are cheaters that can disrupt cooperation between other genes, though many organisms have found ingenious ways to repurpose them. Insects, for example, “borrow” transposon enzymes to circulate their own antiviral molecules, tolerating transposons to receive protection from the even worse threat of viral infection. “It’s the original protection racket” (p. 183).

Those with a background in biology might notice some omissions. Silvertown weaves in a fair amount of history and biographical sketches. He features Lynn Margulis’s theory of endosymbiosis, but not the earlier work on symbiogenesis by Russian botanist Boris Kozo-Polyansky^[2]. Both offered an explanation for the origin of mitochondria and chloroplasts in terms of symbiosis between different single-celled organisms. Similarly, Silvertown includes J.B.S. Haldane, W.D. Hamilton, and genetical explanations for social behaviour in terms of kin selection and inclusive fitness, but he excludes George Price. Granted, his equation has wider applications, but Price dedicated much of his research to the evolution of altruism. Given the amount of ground Silvertown is trying to cover here, his decision to not give a full history of all players is defensible. Silvertown positions himself in the majority camp of evolutionary biologists who explain social behaviours in terms of benefits to self-interested individuals. He considers group selection a “siren call [that] has in the past led thinking onto intellectual rocks” (pp. 191-192) by arguing traits evolve for the good of the species. Though I have no objection to this viewpoint, it does not acknowledge that there is a debate around the levels of selection, nor explain why group selection is considered so contentious. Again, I imagine this will have been a matter of trying to contain how much ground is covered.

“Given that mitochondria and chloroplasts are hundreds of millions of years old, I always considered endosymbionts to be permanent fixtures once evolved. Not so.”

Silvertown’s writing is accessible, meaning this work is not a technical treatise but introduces theory through plentiful examples. Beyond explaining the logic behind the prisoner’s dilemma and Hamilton’s rule, he avoids equations and diagrams and instead relies on inventive metaphors. For example, given that mitochondria and chloroplasts are hundreds of millions of years old, I always considered endosymbionts to be permanent fixtures once evolved. Not so. The transfer of endosymbiont genes to the host’s genome can proceed so far that “endosymbionts themselves can be lost in this manner, leaving nothing but the grin of a Cheshire cat” (p. 71). When yeast cells float freely in suspension, cheats do well, “like a pickpocket in a crowded bar” (p. 114); when they form budding colonies where they are surrounded by clonal copies, kin selection favours cooperative behaviour, because here a cheat “prospers no better than a thief at a pickpocket’s convention” (p. 114). The metaphor of DNA as a blueprint or instruction manual is not correct given the prevalence of transposons; rather it is “part library and part zoo, with the unruly creatures of the menagerie constantly tearing into the pages, creating mutation and mayhem” (p. 177). The book’s concluding message about what this all means for how we should behave is similarly brief but to the point: we can choose to cooperate or cheat, but “just be warned, cheats rarely prosper or, to be exact, only prosper when rare” (p. 192).

That cooperation is an important component driving evolution is most clearly seen when it leads to the formation of a new kind of individual, dubbed a major transition in evolution by John Maynard-Smith and Eörs Szathmáry. Whether it is genes teaming up to form chromosomes, cells teaming up to form multicellular organisms, or individual insects teaming up to form eusocial colonies, this is a two-step process. First, a team is formed where cooperation is favoured through division of labour. Second, the team forms a new entity once its partners become so completely dependent on each other that they cannot reproduce alone. This process offers an answer to two paradoxes. First, if evolution is a gradual process that is not supposed to make large jumps, how do we explain the major discontinuities that we see? “The resolution […] lies in how teams of cooperators are formed and then transformed at major transitions” (p. 188), with new properties emerging that could not have been predicted from the parts. Second is the mistaken belief that evolution has an inherent tendency towards progress. “The appearance of progress is an illusion due to the fact that evolution has produced an accumulation of complexity” (p. 190). Where some have argued that increased complexity over time requires a new biological law, cooperation leading to major transitions offers an alternative explanation.

Selfish Genes to Social Beings is not intended as a formal treatment of cooperation in biology. However, for interested lay readers who are not afraid of a challenge, as well as for biologists coming in from other disciplines, this is a thought-provoking book that holds plenty of surprises.

1. ↑ Youtuber CGP Grey produced a brilliant two-part animated adaptation of the book The Invisible Hook back in 2021.

2. ↑ To his credit, Silvertown instead discusses the to-me unknown history of Paul Portier, who got so close to discovering endosymbiosis already in 1918.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Selfish Genes to Social Beings

Other recommended books mentioned in this review:

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2024 was a year in which I managed to read and review 38 books. What follows is my personal top 5 of the most impactful, most beautiful, and most thought-provoking books I read this year.

1. Jay Matternes: Paleoartist and Wildlife Painter

I instantly fell in love with Jay Matternes’s palaeoart when I encountered it in Visions of Lost Worlds. Science historian Richard Milner spent eight years on this fully authorised career retrospective by Abbeville Press, and it is full of mesmerising palaeo- and wildlife art by an underrecognized master of the genre. Read more…

2. Every Living Thing: The Great and Deadly Race to Know All Life

I read this book as part of a still-ongoing review series. Author Jason Roberts writes an epic history of taxonomy across three centuries that charts the lives, works, and legacy of Linnaeus and Buffon. Published by Riverrun, it quickly became a personal favourite for introducing me to a new intellectual hero. Read more…

3. Eat, Poop, Die: How Animals Make Our World

What a killer title. I was stoked the moment Profile Books announced this one. Fun, fascinating, and always with one eye firmly on the facts, conservation biologist and marine ecologist Joe Roman shows how animals shape ecosystems through their everyday activities. Read more…

4. Playing Possum: How Animals Understand Death

Princeton University Press published this translation from the Spanish original by philosopher Susana Monsó where she provides an exceedingly interesting take on how animals understand death. Playing Possum manages to be both accessible to a general audience and relevant to specialists by showing why comparative thanatology still has a whole lot of growing up to do. Read more…

5. Why Animals Talk: The New Science of Animal Communication

Zoologist Arik Kershenbaum joins Viking Books to deliver Why Animals Talk: a highly stimulating and thought-provoking exercise in decentering the human experience and trying to understand animals on their terms. Read more…

In the category “also-ran”, honorary mention goes to Free Agents: How Evolution Gave Us Free Will and Alfie & Me: What Owls Know, What Humans Believe. I would have loved to include these deeply impressive books as well, except that they were technically published in 2023. If you are looking for more recommendations, do check out my earlier top 5s or browse the archive which lists all reviews.

Finally, some announcements. First, I realise the total number of books read this year is the lowest it has ever been. It is not that I am losing interest, but simply that the same processes of intensification I mentioned last year are still in effect. I am spending more time with each book, taking more notes, doing more background research, drawing on more accumulated knowledge, and writing longer reviews. Second, I intend to continue doing more two- and three-parters and go back to relevant earlier books when touching on certain topics. I hope readers are enjoying the digressions into yesteryear’s books. Once I am finally in control of my to-be-read pile, I hope to feature the occasional classic from decades ago that I keep coming across and have since acquired. Third, you might have noticed that I have abandoned certain social media platforms: their business tactics and management were becoming insufferable. I am really enjoying the crowd on Mastodon, so find me there or sign up here to get email notifications of every new review. I have also opened a Ko-fi account and would like to once again thank the readers who made some very generous donations there: you know who you are. Lastly, I would love to have your feedback! This blog has been running for over seven years now and I am only a few posts away from review #500. I am doing a fair amount of maintenance on older reviews, cleaning up broken links and streamlining the layout I have settled on. I have toyed with ideas such as audio versions of reviews, author interviews, or a newsletter. What would you like to see more or less of?

This is the first of a trio of reviews in which I take a brief detour into ants and collective behaviour more generally. Next up are entomologist Deborah M. Gordon’s 2010 book Ant Encounters and her recent The Ecology of Collective Behavior, but first The Ant Collective. This one grabbed my attention as soon as it was announced. Not a comic or graphic novel, but an A4-format book about ant colonies that is chock-a-block with infographics? Yes, please! Showcasing the best of what science illustration can be and combining it with a genuine outsider’s interest in entomology, The Ant Collective makes for a wonderful graphical introduction that will appeal to a very broad audience of all ages.

The Ant Collective: Inside the World of an Ant Colony, written by Armin Schieb, published by Princeton University Press in May 2024 (hardback, 128 pages)

This book was originally published in German in 2022 as Das Ameisenkollektiv by Kosmos Verlag. It was quickly snapped up for translation into French and Spanish (always a sign of a book’s popularity) before Princeton University Press published it in English in 2024, courtesy of translator Alexandra Bird. Armin Schieb is a freelance science illustrator based in Hamburg, Germany, and this book derives from his master’s thesis in Informative Illustration at the Hamburg University of Applied Sciences. His portfolio shows infographics, 3D models, and cover illustrations for a range of clients, from magazines to newspapers to publishers, but this book represents his first published work to date.

Based on direct observations, sketches, and photos of red wood ants (Formica rufa), Schieb has designed 61 highly detailed computer-generated illustrations showing ants from a bug’s eye perspective that entomologists can only dream of. The eight chapters each contain a mixture of full-page spreads with naturalistic 3D renderings of landscapes full of ants, and pages with numerous smaller infographics that explain how colonies function. Annotations are scattered throughout to provide context to what you are looking at. Neatly, many of the full-page spreads continue overleaf, forming eight-page tableaux. One can only imagine what they would have looked like if the publisher had included them as gatefolds!

Next to obligatory drawings introducing ant anatomy, the focus of this book is on colony-level behaviour, with chapters depicting e.g. nuptial flights, nest establishment and construction, seasonal cycles of nest maintenance, foraging, trail formation, food acquisition and defence, reproduction, nest defence, and the formation of new colonies. The clever use of cutaway illustrations reveals processes that normally play out unseen underground.

“Schieb has designed 61 highly detailed computer-generated illustrations showing ants from a bug’s eye perspective that entomologists can only dream of.”

There are some memorable scenes in here showing e.g. green woodpeckers and boars raiding ant nests. The woodpecker illustration stands out in particular. Red wood ants defend themselves by spraying formic acid and are normally inedible. The birds, though, have turned the tables on the ants twice over, picking them up in their beak and rubbing them on their feathers where the ants discharge the contents of their poison glands. As an added bonus, the formic acid repels feather parasites. This whole story is illustrated by overlaying several semitransparent motion frames of a woodpecker twisting its head and is glorious to behold. Elsewhere, Schieb uses motion blur to good effect to highlight the action-packed nature of spiders and antlions catching hapless ants.

Needless to say, this book is full of fascinating titbits of information. Schieb explains the phenomenon of age polyethism that I first encountered in Ant Architecture. Young ants tend to stay inside or close to the nest, while older ants venture further out to do the dangerous job of foraging (though see my next review of Ant Encounters for some criticism of this idea). Speaking of the next review, Schieb (perhaps unwittingly) offers an excellent illustration of colony behaviour arising through interaction networks when he shows how foraging trails wax and wane as a function of behavioural interactions between ants. There is similarly a deft explanation of the anatomical details of the eyes that allow them to see both polarized and unpolarized light: straight or spiralling stacks of light-sensitive tubules. It is one of those concepts where a picture says more than a thousand words. The only criticism I have of this particular section is that I would have opened it with the otherwise excellent illustration explaining sky polarization. Additionally, I would have added an infographic that explains what polarized light actually is, as it is a surprisingly tricky phenomenon to explain. Michael Land’s book Eyes to See contains a good picture, whereas Schieb basically takes it as a given that readers will understand what he means when writing that “almost all photons in a polarized light ray vibrate in the same plane” (p. 64).

“Over the years, I have reviewed some seriously impressive photographic books on ants […] The Ant Collective rubs shoulders with the greats where visual content is concerned.”

The promotional blurb for the book mentions it draws on the latest science though I was left somewhat confused when I finished it. Schieb is obviously not an entomologist but a graphic artist. There is no mention of the project having benefited from one or several entomologists acting as consultants to give the contents the once-over for scientific accuracy. There is no acknowledgements section where Schieb credits scientists for advice and input. There is not even a list of references or recommended reading included. Or is there? Since I do not have access to the German original I had to resort to some online sleuthing and found a preview on Amazon.de that includes the reference list on p. 126 (shown here). This reveals that, yes, he has consulted books and scientific papers in both English and German, including that evergreen The Ants, an older edition of Insect Physiology and Biochemistry, and both specialist and general German books on forest insects. So, Schieb did his homework, Kosmos referenced it, but for some bizarre reason, Princeton simply omitted it, as the page between 125 and 127 is… blank! Did I just happen to receive a dud to review? Checking eight other copies at the warehouse of the bookseller where I work confirmed that, no, this is a feature, not a bug. Hopefully, if there are future print runs, this is a detail that can be rectified, as it could easily leave readers with the wrong impression.

Over the years, I have reviewed some seriously impressive photographic books on ants, covering amongst others army ants, desert ants, and myrmecophiles. Despite being a slimmer volume written for a general audience, The Ant Collective rubs shoulders with the greats where visual content is concerned. This is a feast for the eyes that will lure newcomers into entomology but should also please seasoned myrmecologists.

A final thing to note is that this book tells the biology of a single species. Wood ants are well-studied as far as ants go, but as the subtitle indicates, this is a look inside the world of a ant colony. It would be a mistake to come away from this book thinking that this is how colonies of all ant species function. As hopefully will become clear in the next two reviews of first Ant Encounters and then The Ecology of Collective Behavior, the world of ants is one of bewildering diversity, though themes and unifying principles are starting to emerge.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

The Ant Collective

Other recommended books mentioned in this review:

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6-minute read
keywords: paleontology

Reconstructing how dinosaurs behaved from just their fossilised bones might seem like science fiction but is very much science fact. Join me for a double review of two recent illustrated books. I will next review An Illustrated Guide to Dinosaur Feeding Biology but first up is Dinosaur Behavior: An Illustrated Guide. Here, 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.

Dinosaur Behavior: An Illustrated Guide, written by Michael J. Benton, illustrated by Bob Nicholls, published by Princeton University Press in October 2023 (hardback, 224 pages)

Dinosaur behaviour has come up previously on this blog. Locked in Time, also illustrated by Bob Nicholls, featured 50 vignettes of famous fossils, while Dinosaurs Without Bones was a chunky pop-science book. In Dinosaur Behavior, 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.

“it becomes abundantly clear that our understanding of dinosaur behaviour relies on two approaches […] new high-tech toys and tools [and] “old-fashioned” comparative anatomy and ethology.”

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 sex for at least some species was a matter of the appropriately named cloacal kiss rather than the brandishing of reptilian genitals.”

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, as I explained in a footnote to another review, 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.

Overall, this is a handsomely illustrated book that offers an accessible introduction suitable for novices and possibly even curious high-school pupils. Since it is December, I will add the words “gift suggestion” to that. Admittedly, serious palaeontology buffs might find the contents here somewhat superficial. So what if you wanted to go deeper on one of these topics, what would that look like? I will next turn to An Illustrated Guide to Dinosaur Feeding Biology to find out. [Edit: As of November 2024, the logical follow-up I would recommend is David Hone’s Uncovering Dinosaur Behavior.]

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Dinosaur Behavior

Other recommended books mentioned in this review:

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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.

What an Owl Knows: The New Science of the World’s Most Enigmatic Birds, written by Jennifer Ackerman, published in Europe by Oneworld Publications in July 2023 (hardback, 342 pages)

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 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).

“A red thread that has been subtly woven through this book is the importance of understanding animals on their terms.”

The same question motivates research on owl vocalizations 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 criticizes 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)? In the just-reviewed If Nietzsche Were a Narwhal, Gregg also mentioned how some scientists do not think it is a useful test paradigm.

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 internalizing 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).

“Ackerman relies on the input of numerous scientists and volunteers. As such, this is as much a book about the people who study owls.”

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 analyzing owl calls. Suddenly, she had a new career and a new group of appreciative ecologist colleagues: “[I] realized 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 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.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

What an Owl Knows

Other recommended books mentioned in this review:

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8-minute read
keywords: crime, reportage, wildlife conservation

This review is a case of coming late to the party. The Wolf (published in the USA as American Wolf) by Texas journalist Nate Blakeslee was published back in 2017, two years before wolf watcher Rick McIntyre’s series of books on famous wolves in Yellowstone National Park was published. I imagine most people will have read Blakeslee’s book first, but for me it was the other way around. Having just reviewed McIntyre’s The Alpha Female Wolf, which tells of the life and death of arguably the park’s most famous wolf, wolf 06, I was left with many questions regarding the hunting of wolves around Yellowstone. Blakeslee’s book turned out to be an excellent companion.

The Wolf: A True Story of Survival and Obsession in the West, written by Nate Blakeslee, published in Europe by Oneworld Publications in October 2018 (paperback, 320 pages)

Let me back up for a moment in case you are new to this topic. The reintroduction of wolves to Yellowstone National Park in 1995 is widely considered a success story in wildlife conservation and they have since been intensively studied by biologists. Their daily lives have been scrutinized by a small cadre of dedicated wolf watchers, most notably Rick McIntyre who has written four books so far based on a lifetime spent in the park. From the start, however, hunters and ranchers in Wyoming, Montana, and Idaho fiercely opposed the project, fearing the loss of quarry and livestock to wolves. As a compromise, the US Fish and Wildlife Service promised that the wolf would be taken off the endangered species list once the population had sufficiently recovered, allowing each state to draw up its own wildlife management strategy. Amidst many political and legal battles, this came to pass in 2009, meaning wolves could be legally hunted again. Against this backdrop, the Yellowstone wolves go about their daily lives, watched and admired by thousands of park visitors, with wolf 06 becoming a legend. When a hunter kills her in December 2012, it sets off a national furore. To Blakeslee falls the unenviable task to weave together all these threads into a coherent whole.

Having reviewed and enjoyed all four of McIntyre’s books, the storyline of the lives of the wolves in the park was familiar to me. Blakeslee has the advantage of having access to other dedicated wolf watchers and their notes, allowing him to present some of the highlights of this multigenerational wolf saga. The Druid Peak pack and wolves 21 and 42 feature, as well as the star of this book, their granddaughter 06. If you are completely new to this topic, the flurry of numerical designations and pack names might be somewhat confusing: the pedigree at the start of the book only shows 06’s lineage. Nevertheless, the narrative Blakeslee pieces together makes it clear why people get hooked on watching wolves.

“[…] the narrative Blakeslee pieces together makes it clear why people get hooked on watching wolves.”

Specifically of interest to me was the biographical sketch of McIntyre, as he barely talks about himself in his books. In my review of The Rise of Wolf 8, I mentioned his passion borders on the obsessive and Blakeslee confirms and fills out that picture for me. A sweet man possessed of a nearly child-like innocence, he is socially awkward and prefers his own company. The same compulsion that drove him to get the perfect shot in his previous career as a wildlife photographer, with some pictures published in National Geographic, now drives him into the park, at times risking his life to see wolves every single day. The thought of writing and promoting books, and thus leaving behind his daily routine in Yellowstone, makes him uncomfortable. And thus he keeps religiously recording everything he observes until it becomes an end unto itself. Fortunately for us, he eventually breaks that addiction, but not until two decades have passed.

The polar opposite of those who watch wolves are those who want them dead. Though, as Blakeslee shows, attitudes amongst hunters and ranchers are a bit more nuanced than that. Some, including wildlife biologists, argue pragmatically that predator populations need managing to protect livestock. Others, such as the man who killed wolf 10, will ride their horse down the local high street during Independence Day, proudly sporting a t-shirt that reads “Northern Rockies Wolf Reduction Project”. What many share is an aversion to outsiders, both out-of-state hunters and the wolf groupies flocking to the park. But I think Blakeslee captures the heart of the conflict when he writes that this is about federal overreach: “wolves were just the latest flashpoint […] the real struggle was over [management of] public land” (pp. 127–128).

And then there is the hunter who shot 06. A friend is willing to pass on Blakeslee’s contact details and the man, here pseudonymized as Steven Turnbull to protect his identity, reaches out to tell his story. An outdoorsman besotted with big-game hunting, he is unrepentant, boasting he would do it again. He is genuinely mystified by the enthusiasm of wolf watchers and maintains that he has done nothing wrong. I think Blakeslee gives a fair portrayal of Turnbull, allowing him to unload his story without judging him, although there are details he is not impressed with. To me, the whole concept of trophy hunting is just… alien, and coming to any sort of mutual understanding seems impossible. Blakeslee seems to feel the same when Turnbull shows him 06’s pelt and invites him to stand next to it to marvel at its size: “it felt profane, though I had no idea how to explain to my host why” (p. 261). Perhaps surprisingly, to me, Turnbull does not emerge as the book’s antihero.

“If there are villains here, they would have to be the governors and senators for who the wolves are just pawns in political power games. “

If there are villains here, they would have to be the governors and senators for who the wolves are just pawns in political power games. The wolf is delisted, declared protected, and then delisted again as various interest groups thwart each other through court cases and political shenanigans. This includes a very brazen overturning of a court ruling protecting the wolves via a last-minute provision snuck into a must-pass federal budget bill, a so-called rider. This was exactly the backstory that McIntyre, as a former National Park Service employee, carefully avoided commenting on in The Alpha Female Wolf. What also becomes painfully clear is that federal agencies, e.g. the US Fish and Wildlife Service, and various state agencies primarily serve the interests of hunters and ranchers. Wildlife protection is a happy coincidence if it happens to align with e.g. maintaining population levels of game.

Despite providing much sought-after context to the complicated situation around wolf reintroduction, the book did feel slightly uneven in places. Montana has always been a swing state in national elections, and in 2010 its Democratic senator is up against a Republican candidate who is making populist anti-wolf noises that are winning him votes. Admittedly, I’m not well-versed in US politics, but it seems a bit far-fetched when Blakeslee writes that “if Democrats were going to keep a toehold on power in Congress—if Obamacare was going to live past its infancy—wolves needed to start dying in Montana, in large numbers, and soon” (p. 158). Can national politics really be reduced to wolves? Similarly, when he covers the 2010 lawsuit that sought to return wolves to the endangered species list, the arguments from lawyers arguing in favour are given the most space, while the arguments from those against are described in a mere two pages. Furthermore, Blakeslee does not talk to any ranchers who lose livestock to predators, something Philippa Forrester did in her recent book on Yellowstone wolves. Finally, Blakeslee’s discussion of trophic cascades in the park as a result of wolf reintroduction tends towards a simplistic portrayal of wolves as some sort of canine fairy dust that you can sprinkle on broken ecosystems to fix them. Only in the source notes does he briefly mention that e.g. wolf biologist David Mech has warned against simplistic interpretations, something I also touched on in my review of Yellowstone Wolves.

This criticism notwithstanding, overall The Wolf succeeds in bringing together many disparate strands and weaving them into a captivating book. I found it a very useful companion to McIntyre’s writing but it also shines as a standalone book that tells of the fascinating lives of wolves in Yellowstone and the passions stirred by their reintroduction.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

The Wolf

Other recommended books mentioned in this review:

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One has to wonder whether the horror writer H.P. Lovecraft had the star-nosed mole in mind when he created the Cthulhu Mythos. Fortunately for us mortals, this little mammal is harmless—though it is not without some extraordinary powers of its own. I first came across the work of biologist Kenneth Catania in the recently reviewed Sentient and had to dig deeper. Great Adaptations is a personal and entertaining account of his almost-five decades career investigating the biological mysteries of the star-nosed mole and other creatures.

Great Adaptations: Star-Nosed Moles, Electric Eels and Other Tales of Evolution’s Mysteries Solved, written by Kenneth Catania, published by Princeton University Press in October 2020 (hardback, 199 pages)

Why does the star-nosed mole have a crown of tentacles front-and-centre of its face? A young and enthusiastic Catania got the chance to delve into their world when the head curator of the National Zoo in Washington, DC told Catania’s father he was looking for a volunteer to care for them, and maybe do some research. Starting with the idea that it might be for electroreception (it is not), Catania takes you down the research rabbit hole. He examines noses under the electron microscope to reveal Eimer’s organs and other specialised touch sensors. He enlists the help of a neurobiologist to show how the neocortex contains a literal sensory map of the nose. Curiously, the smallest pair of the 22 tentacles takes up most neocortical real estate. Examining embryos reveals not only that this pair of tentacles develops first and is the most sensitive, but also that the crown forms quite unlike any other appendage. Not by extrusion of tissue, nor by trimming excess tissue via programmed cell death, but as backwards-facing tubes that detach and bend forward during development. But what is this curious organ for? The use of high-speed video cameras shows the mole to be extremely fast at detecting, recognizing, and consuming invertebrate prey, taking on average just 230 milliseconds to do so.

There are some nice biology lessons hidden in this whirlwind of observations and remarkable experiments. Why is so much of the neocortex devoted to the smallest pair of tentacles? Catania draws a comparison to our eyes where we focus the image on a small, well-innervated area of the retina called the fovea. The smallest pair of tentacles act as a touch fovea: “instead of making the sensor […] high-resolution throughout, requiring vast neocortical territory for all the sensory processing, a single small area is analyzed in detail, and moved around a bit like a sensory flashlight” (p. 40). Why does the mole’s nose develop in such an odd fashion? He reminds the reader that the process of evolution has to tinker with what is available and cannot start from scratch, a recurrent theme in evolutionary biology. There is good reason to think that the mole’s ancestor had a nose with a proto-star. And why such a sensitive nose? Catania draws on foraging theory to argue that the mole is exploiting an unlikely niche space: by minimising prey handling time it can eat small prey that would normally not be energetically profitable for a warm-blooded mammal of its size.

“Great Adaptations is a personal and entertaining account of [Catania’s] almost-five decades career investigating the biological mysteries of the star-nosed mole and other creatures.”

Catania brings in an interesting idea, the “rare enemy effect”, when discussing the next two animals he has studied: the tentacled snake and human worm grunters. The snake hunts fish underwater and sports two tentacles on its snout that, as Catania shows through careful observation, are motion sensors. By exploiting the fish’s hard-wired escape response, the snake tricks fish to swim into its gaping mouth. Worm grunting is an old practice that humans use to collect earthworms for fish bait. By sticking a wooden rod into the ground and rubbing it with a piece of metal, the grunter creates subterranean vibrations that cause earthworms to emerge on the surface. Charles Darwin already suggested that earthworms might be fleeing the vibrations caused by their usual nemesis: moles burrowing in the soil. With the help of an experienced grunter, Catania confirms this idea and mentions other observations on animals such as gulls that also exploit this trick to bring food to the surface. In both cases, the question is why the fish and worms have not evolved a response. He invokes what Richard Dawkins calls the rare enemy effect: “A rare predator may have such a small impact on the large prey population that no counteradaptation ever evolves” (p. 75). The predators are getting away with trickery.

Similarly fascinating is Catania’s work on electric eels and predatory wasps. The former have an important place in the history of scientific discovery of electricity, inspiring no less than Alessandro Volta when he designed his batteries. Using ingenious experimental setups, Catania figures out how eels stun their prey (somewhat like a taser) and what the function is of shorter double bursts of electric discharge (blowing the cover of any edible prey in hiding when they involuntarily twitch). Meanwhile, the story of predatory wasps that turn cockroaches into zombified hosts for their offspring makes for engaging popular science. Catania’s contribution is to figure out the exact sequence of events by which the wasp overcomes the cockroach’s defences and violently subdues it. Though, as he shows, a prepared cockroach can hold its own and deliver some mighty kicks with its barbed hindlegs.

“It is […] easy to communicate [this sort of research] to a general audience as it does not require prior knowledge. [This research], and by extension this book, is a gateway drug to biology.”

Next to entertaining science experiments, Catania wrote this book to tell the stories that never make it into the published literature. Of the friendships with the people whose permission you seek to collect moles on their land, or the worm grunter who happily helps you out gathering data. The book is peppered with some genuinely entertaining anecdotes and personal interest stories. Catania has furthermore included photos, still frames from video clips, and diagrams to illustrate his work. As many of his experiments involved filming behaviour with high-speed cameras, some figure legends cleverly include QR codes that will take you to short clips on YouTube^[1].

Above all, Catania wrote this book to convey the sense of wonder that accompanies scientific discovery. The main reason I thoroughly enjoyed Great Adaptations is that it spoke to me on a very personal level. This is the sort of research that attracted me to biology in the first place (and which I have had the fortune to do myself). It is also easy to communicate to a general audience as it does not require prior knowledge of, say, genetics or ecological theories. All it needs is for you to observe animal behaviour with a healthy dose of curiosity and start asking questions. This kind of research, and by extension this book, is a gateway drug to biology. If I could go back in time 20 years I would be that student sitting in the front row during Catania’s lectures, and beseeching him afterwards about doing a research project in his group. Lacking a time machine, this book is the next best thing.

1. ↑ For those readers without a smartphone, there is, unfortunately, no separate list of URLs but you can find the channel here.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Great Adaptations

Other recommended books mentioned in this review:

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Despite, or perhaps because of, the ongoing pandemic, 2021 was a phenomenal year for publishing. Though I did not get to nearly as many books as I would have liked, I read and reviewed 67 books this year. 

What follows is my personal top 5 of the most impactful, most beautiful, and most thought-provoking books I read during 2021.

1. Islands of Abandonment: Life in the Post-Human Landscape

Cat Flyn’s debut with HarperCollins is a poetic and spellbinding travelogue to dystopia that is surprisingly rich in ecological and biological detail. Islands of Abandonment explores how nature rushes back in when humans abandon places. It haunted me long after I finished it. Read more…

2. Life’s Edge: The Search for What It Means to Be Alive

A new book by Carl Zimmer is always reason to be excited. Life’s Edge is a fascinating exploration of the borderlands between the living and non-living world, showing how hard it is to answer the question of what life is.  It also cements Zimmer’s reputation as one of today’s finest science writers. Read more…

3. Beasts Before Us: The Untold Story of Mammal Origins and Evolution

Even though mammals have a long and rich evolutionary history that predates the dinosaurs, their early evolution is somewhat neglected in popular writing. Beasts Before Us tells their story. This spectacular debut of Scottish palaeontologist Elsa Panciroli shows her to have a fine way with words. Read more…

4. Ant Architecture: The Wonder, Beauty, and Science of Underground Nests

More ants this year! Ant Architecture shows how you can do groundbreaking research on a shoestring budget. Entomologist Walter R. Tschinkel has been making three-dimensional casts of ant nests for decades and discusses the fascinating scientific questions this throws up. Beautifully illustrated and phenomenally written, this is unlike any other book on insects you have seen before. Read more…

5. Plagues upon the Earth: Disease and the Course of Human History

A whopper of a book at almost 700 pages, Plagues Upon the Earth is a magnificent environmental history of infectious disease that stands out for its nuance and readability. Much more than a potted history of “celebrity” diseases, historian Kyle Harper revisits existing narratives in light of new data and methods. My recommendation of the year for background reading on the COVID-19 pandemic. Read more…

If you are looking for more recommendations, do check out my top 5s for 2020 and 2019. I have also recently added a single-page archive listing all reviews.

You would think that after centuries of studying spider webs we have a pretty good grasp of them. Yet a thorough, book-length review of their construction, function, and evolution has been missing. Emeritus Professor William Eberhard has taken on that colossal task, based on his nearly 50 years of observing spiders and their webs. Some works go on to define their discipline. Spider Webs has all the trappings of becoming the arachnological benchmark for many years to come.

Spider Webs: Behavior, Function, and Evolution, written by William G Eberhard, published by the University of Chicago Press in August 2020 (hardback, 658 pages)

Spider Webs is big. Really big. This arachno-tome intimidates as much as it edifies. Some stats: A 21 × 28 cm, 658-page hardback containing ten chapters sprawling over 581 pages, 39 pages of references, and a 36-page index. A 12-page table of contents revealing the book’s highly nested structure, many sections going down 4–6 levels (you may find yourself reading section 3.3.4.2.2.5 on the importance of UV reflectance of silk stabilimenta). Almost 300 black-and-white photos and drawings of webs, often of species not included in previous literature. And if that was not enough, a 91-page online supplement with small print containing additional observations, tables, and musings. What makes these numbers mildly terrifying is that Eberhard almost apologetically mentions he avoids so much detail as to overwhelm the reader, and that “a truly thorough summary of our current knowledge would be crushingly dull” (p. 10). Yes, 750 pages is what Eberhard holding back on his encyclopedic knowledge looks like.

So, what is in the book? Eberhard includes much older literature often skipped over in review papers, and has included numerous of his own unpublished observations. He starts with a chapter on the spider’s hardware (silk glands, spinnerets, and legs) and ends with two chapters on evolution. The construction and function of webs in chapters 3–8 forms the core of the book, though the order in which topics are discussed is not necessarily how a spider proceeds. Thus, Eberhard begins with an extended chapter on the function of orb webs, including 45 pages discussing incorrect and unsupported ideas, followed by a chapter on the many trade-offs between different properties and parts of a web, e.g. tensions on lines or the number and spacing of radii and spirals of sticky silk. Having discussed function, Eberhard then turns to how webs are constructed and what cues spiders use. For non-orb weavers our knowledge is so fragmented that a short chapter summarises “scattered bits and pieces of information” (p. 273). Orb weavers have been much better studied, and the descriptions of building behaviour (how a spider moves its legs and body to make an orb web) and the cues used to decide where to lay and attach lines span 120 pages in two chapters. And thus the first step in the process, how a spider decides where and whether to build a web, is discussed last. The properties of spider silk are only discussed briefly, and I refer readers wanting more details to two books by Catherine Craig.

“[…] published descriptions of webs and spider behaviour make it appear as if there are only a few ways of doing things, but that is a limitation of our language, not a reflection of reality.”

Spider Webs is not a particularly difficult book. Eberhard wanted it to be accessible to the general reader and has by and large succeeded, I think. Any reader serious about tackling a book this size is probably already familiar with the terminology and conventions used here. If not, no harm can become the spider novice from first reading e.g. Biology of Spiders. Spider Webs is, however, particularly rich in detail and minutiae. This is where the highly nested chapter structure comes into its own. I found it useful to bookmark the contents and refer to them while reading to keep my bearings. Throughout, there are summaries in subsections and summaries at the end of chapters, and summaries of summaries. The take-home messages are spelt out clearly, and I will highlight a few prominent ones.

Eberhard warns against typology: published descriptions of webs and spider behaviour make it appear as if there are only a few ways of doing things, but that is a limitation of our language, not a reflection of reality. “The” web does not exist: there is much variation on the level of families, genera, species, and even individuals in the details of web construction, much of it poorly documented. There are fascinating variations on the theme (the elongated ladder webs to catch moths are but one of many examples included here). And this is before you even consider the material here on non-orb weavers. Tying in with that, the idea that spiders are little web-spinning automatons is mistaken. True, freshly hatched spiderlings succeed at their first attempt, and there is little indication that spiders improve with practice, but they combine information from a wide variety of cues (environmental and otherwise) during web construction and can modify their behaviour as needed. Eberhard discusses 10–16 cues, depending on how you count and which ones you consider independent of each other.

“A particular sticking point is ecological realism. Much data that is collected […] is flawed or of questionable relevance to spiders.”

Orb webs are not optimum structures: “[…] there is a veritable minefield of variables that can affect the chances that a web will capture prey” (p. 78). Despite claims to the contrary, demonstrating optimality is very hard and, Eberhard believes, has never been done empirically. Nor are orb webs the pinnacle of evolution. Despite the higher-level phylogeny of spiders not being fully resolved, there is little doubt that orbs have evolved and secondarily been lost again multiple times. The large-scale evolutionary pattern is one of both high diversity and frequent convergence, resulting from “an especially ancient and thorough exploration of the adaptive space associated with webs” (p. 479). In other words, given hundreds of millions of years of evolution, is there anything spiders have not tried? (Actually, yes, as shown here by some interesting comparisons with other silk-producing insects.)

Next to everything we know, Spider Webs is as much a book about what we do not know. Eberhard reviews the many suggested functions of web traits, only to point out that, bar preliminary results or casual observations, we often lack empirical data to decide one way or another. He concludes an extended discussion on the possible functions of silk stabilimenta with the admission that it sounds like a “litany of frustration” (p. 180). I had not heard of them before, but they will have even seasoned arachnologists pull out their hair. A particular sticking point is ecological realism. Much data that is collected (on e.g. number of prey available in the environment or their nutritional value) is flawed or of questionable relevance to spiders: “the cues that are used by spiders are not necessarily the same as the variables that are commonly measured by researchers” (p. 435). And we must not forget that spiders evolved in habitats undisturbed by humans until recently. Most data is now gathered in environments that spiders did not evolve in. He admits this might seem like: “nihilistic surrenders to hopeless ignorance” (p. 87).

“Spider Webs is one of those rare books that sets a discipline’s research agenda for decades to come and cannot be ignored.”

Eberhard berates fellow arachnologists throughout, e.g. for not documenting variation in construction behaviour and design within species, or the lax use of the word “sheet” when describing webs. But he is equally critical of his own failures and owes up to his changes of mind. For instance, his enthusiasm for using models to determine the advantages of different web designs has vanished, and he is no longer the proponent he was of using artificial webs to estimate prey availability. Table 9.4 lists beautiful ideas slain by ugly facts and “gives a sampler of disappointments (with my own failures perhaps over-emphasized)” p. 480. As a bonus, there is a 15-page table in the supplement with hundreds of unanswered questions for future students and researchers to pursue. One might think Eberhard a curmudgeon, but that would ignore the fact that nature is complex and does not readily yield to the order that we wish to impose upon it. Here is someone who has studied spiders intensely and I must agree with his outlook that “intellectual rigor is useful; little is gained (and much is lost) by ignoring the limitations of data to support or discard particular conclusions” (p. 87).

Spider Webs is one of those rare books that sets a discipline’s research agenda for decades to come and cannot be ignored. This book has set the bar and has set it high. For professional arachnologists this is a vital and invaluable reference work. For serious spider enthusiasts it is an absolute treasure trove. Beyond the spider community, however, there is much here of interest to ethologists and evolutionary biologists. Readers interested in more spider talk might also want to check out my Q&A with Eberhard published over at the NHBS Conservation Hub.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Spider Webs

Other recommended books mentioned in this review:

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The reintroduction of wolves to Yellowstone National Park is one of the best-known examples of wildlife conservation. To celebrate its 25th anniversary and summarise the many lessons learned, Yellowstone Wolf Project leaders Douglas W. Smith and Daniel R. Stahler, together with wildlife ecologist Daniel R. MacNulty, bring together research from over 70 colleagues in this large, edited collection. The combination of academic content, excellent photography, guest essays, and an online bonus documentary with interviews make this the go-to reference work for anyone wanting to go beyond the headlines on this reintroduction project.

Yellowstone Wolves: Science and Discovery in the World’s First National Park, edited by Douglas W. Smith, Daniel R. Stahler, and Daniel R. MacNulty, published by the University of Chicago Press in December 2020 (hardback, 339 pages)

The first thing that struck me about Yellowstone Wolves is how well-organised the book is. Six parts contain nineteen chapters, none going beyond twenty pages, and most include a clearly signposted conclusion. To give equal airtime to so many different studies and opinions is remarkable—the six years the editors spent on this book have borne fruit. The second thing is how readable the book is. To do justice to the subtleties and complexities of real-world ecosystems means digging into scientific research. Thus, it discusses methodologies and research results and provides graphs galore, but without bogging the reader down with excessive jargon or complex statistics. Only occasionally, when the discussion turned to species interactions or ecosystem ecology, did I feel that I was reading an academic paper.

So, what have we learned from 25 years of having wolves back in Yellowstone? This book covers a wide range of topics, more than I can hope to discuss here. Sensibly, it opens with a short history of the park, wolf extermination, and the reintroduction—a dramatic story complete with last-minute lawsuits that almost scuppered the whole operation.

“The first thing that struck me about Yellowstone Wolves is how well-organised the book is. […] To give equal airtime to so many different studies and opinions is remarkable”

After some basic wolf biology, the bulk of the book discusses long-term research. This covers pathogens and parasites, the genetic studies that inform wolf pedigrees and explain why you see both black and grey wolves in the park, and, notably, the different aspects of wolf packs. How they form, how long they last, how they defend territories and compete with one another, and how they change over time. This introduces some of the legendary wolves from Rick McIntyre‘s Alpha Wolves of Yellowstone series, or the very popular female O-Six, but also reveals the value of older wolves to their pack, or the surprisingly high mortality due to intraspecific (i.e. wolf-wolf) conflict when wolves are not constantly hunted by humans.

My impression, however, is that the seven chapters across parts 4 and 5 will be the most relevant to many readers. Why? First, because the chapters on community ecology (particularly wolf-prey interactions) touch both on the concerns of the hunters and ranchers who opposed wolf reintroduction, and on the challenges faced by generations of park managers. Second, because the topic of ecosystem ecology (the effects of wolves on ecosystems) catapulted the park to internet fame.

We are going to need some history here.

Woven throughout this book is the story of how predator removal at the beginning of the 20th century saw elk populations boom, leading to concerns of too many elk overgrazing and trampling the park and surrounding farmland. From 1920 to 1968 park management and hunters culled and relocated tens of thousands of elk, leading to concerns of too few elk and, from 1969 onwards, new policies that let nature take its course. Predictably, without predators, there was a new elk boom. This is the context in which wolf reintroduction was finally put on the table.

“Of course, wolves eat elk, but the devil is in the details […] these chapters seek to correct misconceptions [as] wolves are not the ungulate killing machines some imagine”

Elk numbers have since declined again, causing—you cannot please everyone—renewed consternation. This time, though, wolves get the blame. Of course, wolves eat elk, but the devil is in the details: “what is in doubt is the size and timing of [their] contribution” (p. 187). So, these chapters seek to correct misconceptions. Though wolves are formidable pack hunters capable of taking down large prey, failure is frequent and the risk of injury high. Lacking the powerful bite and retractable claws of big cats or the muscular forelimbs of bears, wolves are not the ungulate killing machines some imagine, instead preying on young, old, and sick elk, or scavenging e.g. bison carcasses. Furthermore, elk decline started months before the wolves returned to Yellowstone in 1995. In subsequent years other predators such as cougars, bears, and coyotes also flourished, while hunters continued to shoot substantial numbers of elk just outside the park. Guest contributors weigh in here with lessons learned from other long-term wolf studies in national parks such as the island of Isle Royale, Banff, and Denali.

The other controversial topic tackled is ecosystem effects: the idea that the impact of predators on prey affects the prey’s food base, rippling down the food web and influencing a whole ecosystem. Now, such trophic cascades do occur in nature, but in Yellowstone’s case, the narrative has been hijacked by that one viral video clip, How Wolves Change Rivers. It presents a straightforward story of wolves killing elk, which reduced elk overgrazing of trees, in turn stabilising river banks and leading to the return of numerous animals. Broken ecosystem? Just add Wolves! Obviously, I am being facetious. In her contribution to Effective Conservation Science, Emma Marris examined the clip, the accusations of oversimplification, and the power of a good story. Ben Goldfarb, in his book Eager, noted that it downplays the effect of beaver reintroductions.

“the topic of ecosystem ecology […] catapulted the park to internet fame […] trophic cascades do occur in nature, but in Yellowstone’s case, the narrative has been hijacked by that one viral video clip”

Given this background, I was very curious to see how this book dealt with the matter. In one word: circumspect. The clip is only hinted at: “Some videos on the topic have garnered online audiences of millions. Although scientists have discredited some of these works as romantically simplistic […]” (p. 257). One chapter has a research group present the argument in favour of trophic cascades. They admit that indirect effects on vegetation have not been observed everywhere in the park where wolves now roam and add that players such as beavers, bison, wildfire, and disease complicate the picture. The next chapter has another research group consider more complex networks of interactions between wolves, other predators such as bears and cougars, scavengers, and herbivore prey. They open by writing that: “the preceding chapter considered […] processes in a single oversimplified food chain (i.e. wolves-elk-aspen/willow) in Yellowstone. Here, we discuss a broader set of food web relations that are too often ignored in the push to explain the links between wolves, elk, and vegetation” (p. 223). And so the discussion rumbles on.

The book ends with very relevant chapters on park management that explain the rationale behind visitor rules, celebrate dedicated wolf watchers, and hash out a framework for the perenially controversial topic of transboundary wolf management. That last one, in layman’s terms, gives recommendations for wildlife agencies on dealing with predators that cross the borders we draw on maps and come into conflict with stakeholders such as ranchers or hunters living near national parks.

As noted elsewhere, Yellowstone’s wildlife is subject to continuous change. By reintroducing wolves, scientists have had the unique opportunity to study the complexities of living, breathing ecosystems. Written by the very people who spent decades in the field doing the research, Yellowstone Wolves is a formidable achievement that presents a wide range of scientific topics in a well-organised, readable, and beautifully illustrated book.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Yellowstone Wolves

Other recommended books mentioned in this review:

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