May 12, 2023 by Hope Reese
If you think your pet cat has a wild side, you’re not wrong. According to evolutionary biologist Jonathan B. Losos, “housecats aren’t that different from mountain lions.” In his latest book, “The Cat’s Meow: How Cats Evolved from the Savanna to Your Sofa,” Losos guides readers through the evolutionary history of felines, uncovering the ancestral roots of the modern housecat.
Not to worry: This isn’t another cute cat book. Instead, Losos, a professor at Washington University in St. Louis whose specialty is studying a large family of tree-living lizards known as anoles, taps deeply into a wide range of feline research, from digital tracking of nighttime activity to DNA testing, to show how much we’ve learned so far about cats — and how much is still left to discover.
The earliest cats lived about 30 million years ago — the species we now call Proailurus lemanensis — but about 10 million years later, evolution “kicked into gear,” Losos writes, when felines diverged into two groups: the saber-toothed cats, which eventually became extinct, and the conical-toothed group, which evolved into today’s Felis catus. Genetically linked to the North African wildcat Felis silvestris lybica, the first domestic cats appeared about 10,000 years ago. Most researchers believe that living near humans in early agrarian communities, where cats presumably shared food and helped control rodents — a mutually beneficial arrangement — probably led to the domestication of today’s housecats.
While there is a substantial fossil record for the saber-tooth line, the conical-toothed group is much harder to trace back. Today, there are up to 42 species of wild felines derived from the conical branch – including ocelots, bobcats, lions, and cheetahs. “Big cats are the celebrities of the feline world,” Losos writes, but most species are about the size of a housecat and look quite similar. “Quick test: how many cat species can you think of that weigh less than fifty pounds?” he challenges the reader. “Clearly, the little-cat side of the feline family needs a better PR agent.”
The extraordinary diversity of today’s cat breeds “occurred in decades rather than millennia,” Losos notes. And while selective breeding has led to at least 73 breeds of domestic cats — hairless, floppy eared, Siamese, and so on — most are little changed from their wild ancestors. “Look underneath the paint job — the variation in hair length, color, and texture — and most domestic cats are nearly indistinguishable from wildcats,” he writes. “The differences in anatomy, physiology, and behavior that distinguish most domesticated species from their ancestors don’t exist in cats.”
Losos goes on to spend a good chunk of the book explaining the similarities and differences between housecats and their wild ancestors. “Whereas dogs have diverged from wolves in many genes, domestic cats and wildcats differ in only a handful,” Losos writes. “Cats truly are scarcely domesticated.”
In 2014, geneticists at Washington University in St. Louis sequenced an entire genome (of about 20,000 genes, similar to humans) of a cat named Cinnamon. Only 13 genes “showed evidence of having been changed by natural selection during the domestication process,” he writes. In a wolves-to-dogs comparison, meanwhile, there were almost three times as many. In fact, Losos prefers the term “semidomesticated,” since the cat’s evolutionary history is so different from the dog and other domesticated species.
The small fraction of altered genes, plus the high similarity in anatomy and behavior between housecats and wildcats, demonstrates how similar housecats are to their ancestors — even though they are different species, Losos writes. Another telltale sign of how close the two are: the speed with which a domesticated cat will lose its socialization skills and quickly adapt to living in the wild.
That said, today’s housecats exhibit many behaviors that seem to be linked to their relationship with humans. In fact, the very thing that distinguishes them from their ancestors is that they get along with us. Their purring, meowing, kneading, and hunting habits (they don’t hunt in groups, for instance) have all diverged from their African forebears.
Losos is a quirky and engaging writer. His book covers virtually everything cat-related — from research into feral cat populations and how much mileage cats cover in their nighttime wanderings, which can be tracked through special GPS collars, to breeding preferences and why a cat’s tail, when held up straight, is a friendly sign (it’s a signal to strangers from a long distance).
We learn that the neighborhood of Nachlaot in central Jerusalem “boasts the highest concentration of cats ever recorded anywhere in the world,” according to Losos — equivalent to 6,300 per square mile — and is the site of important research into the traits of both domesticated and non-domesticated cats.
Regarding natural selection, Losos reveals that male lions who take control of a new pride often kill the newborns of female lionesses fathered by other males. It’s an adaptation that makes evolutionary sense, he maintains, as the lionesses will more quickly bear cubs fathered by the new males, furthering their genes. Male housecats, on the other hand, don’t work together in lion-like coalitions; they are solitary and tend to move from one female to the next, racking up as many sexual partners as possible. (Though they have been known to occasionally exhibit infanticide.)
Losos himself owns three cats, and often draws on his personal observations to shed light on the nuances of housecat behavior, such as the frequency of cat fighting. “In one survey,” he notes, “45 percent of respondents who live in multicat households reported fighting among their cats at least once a month.”
Along the way, he visits some debates that he prefers not to wade into at length, such as the ethics of breeding, though he says there is one practice about which “there should be no debate: declawing and similar procedures are mutilation and are morally indefensible.”
Losos frequently mentions the shortcomings of current feline research. How did purring evolve, for example, and why do kittens knead? “From topics as disparate as what’s going on in their heads, what impact they have on North American wildlife populations, and where exactly they were domesticated, there’s a lot left for us learn,” he concludes.
But it remains difficult to determine which traits are unique to housecats, since their evolution has been complicated by interbreeding: “Wildcats the world over appear to be interbreeding willy-nilly with domestic cats,” he writes.
Even as many other wild cat species become increasingly endangered, Losos contends that there’s “no doubt” that today’s domestic cats — currently some 600 million — will continue to thrive. Just as the first cat species, 30 million years ago, spawned cheetahs, lions, and more, “time will tell whether Felis catus spawns an equally rich evolutionary lineage,” Losos writes. “I wouldn’t bet against it.”
Hope Reese is a journalist in Budapest, Hungary. Her writing has appeared in The New York Times, The Atlantic, Vox, and other publications.