Cats and People: Children of the Ice Age

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Just how far back do people and the ancestors of domestic cats go? All the way back to Plio-Pleistocene times, when the ice ages began.

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Black Cats and Black Panthers


Black house cats and black panthers (leopards) have a couple things in common. Beautiful, beautiful things.


(Here’s how they filmed that and other slow-motion cat videos.)

Domestic cats and leopards are both felids, i.e., they both belong to the cat family Felidae. They also show melanism (the technical name for black fur).

And that’s about it for the similarities between these two species. Size, of course, is a big difference. Where they hang out matters, too.

Black house cats cluster in urban centers around the world, while other melanistic cats are usually found in humid tropical environments.

Different genes are also involved in the mutation, including ASIP changes in the domestic cat and MC1R changes in some other melanistic felids.

Since the natural mammal fur pattern fur is agouti–a brindled appearance caused by alternating light and dark bands of color on each hair–scientists are fascinated by feline melanism. They study it with techniques ranging from mapping populations in the field to the latest molecular biology lab tools.

We don’t have to get into that much depth here, but some of their findings are very interesting.

Domestic black cats

Mapping and archaeological studies suggest that the fur mutation that turns domestic cats black is ancient. It probably happened around 2,500 years ago, somewhere in the eastern Mediterranean. (Todd) All of the cats shown in Ancient Egyptian artwork are tabbies, like their African wildcat ancestor, so this probably didn’t happen in the Land of the Pharaohs.

Black cats then spread west together with various Mediterranean commercial nations, including the Phoenicians. Today, despite being a target during the bad old days of witch hunting in Europe, black cats are very common in the UK, along the northwestern coast of Africa, and in a natural trading corridor along the Seine and Rhône river valleys that once saw heavy traffic as a barge shortcut between Britain and the Mediterranean. (Todd)

You can also find lots of black cats in urban settings like Utrecht (Netherlands), Chiang Mai (Thailand), Denton (Texas) and some other US cities, and Morocco. (Bradshaw)

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It’s not always one big happy family. Ryusuke. CC BY 2.0.

No one really knows why this mutation has worked out so well for domestic cats. Whatever the secret, humans probably are involved because other black cat species have a very different story.

Black panthers and other wild cats

Black leopards and jaguars are very popular cultural icons, but more than a third of the cat family shows melanism in some individuals. (da Silva and others)

These include, but aren’t limited to:

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I could only find a gray Asian golden cat (black with some other genetic things going on) online. Umeshsrinivasan. CC BY-SA 3.0.

Yes, the cat family is so beautiful and varied that it will take a separate ebook in this planned series to do its many members justice.

In case you’re wondering about the other three big-cat superstars, all-black lions and cheetahs have been reported (Sunquist and Sunquist) but not confirmed. Tigers are a special case.

It’s probably not coincidence that these black cats live in the tropics, but moisture rather than lush vegetation seems to be the deciding factor.

For instance, on the very wet southern part of the Thai/Malaysian Kra Isthmus, almost all leopards are black. Not so in the slightly drier northern section, where there is a mix of melanistic and mainstream spotted leopards, although the plants are exactly the same. (da Silva and others)

Why? No one knows. Proposed explanations run the gamut from camouflage to body temperature regulation and antibacterial effects.

Evolutionary advantages

All that is literally worlds away from the domestic black cat, which seems to do well around people no matter what the relative humidity may be. Nevertheless, black apparently gives cats some kind of advantage in life.

Non-agouti domestic cats–those that lack the alternate light/dark color bands that most mammal fur has–tend to be black, though other solid colors are possible. I’m not sure why, though I have read that the light brown background color on a tabby cat is an optical illusion caused by alternating bands of light color and black, with a light-colored band just under the hair tip. (Lyons) (Other mutations are involved in a true brown color in cats.)

Black may just be a very common pigment in the African wildcat/domestic cat’s color palette.

Genes can have more than one effect, and maybe black cats have been so successful because they are a little better at interacting with humans than other domestic cats. Their appearance is certainly striking; perhaps we just tend to choose black cats over others.

That’s all artificial selection, according to evolutionists. It’s human-mediated.

Natural selection may be at work, too. Since street lighting is a relatively recent invention, it’s possible that black fur may have given cats a better ability to hide at night as they roamed the urban streets. They lived longer and had more kittens.

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Street lighting also works, by throwing shadows that black cats can use while hunting or hiding from predators. the2me at Pixabay. Public domain.

Zoologists get a little more technical. They know that most wild mammals have the agouti pattern and most domesticated mammals are non-agouti. However, overall the domestic cat population is about half agouti and half non-agouti.

This equilibrium makes some researchers suspect they have what is called a heterozygote advantage (Todd)–the non-agouti gene is recessive, meaning it can stay hidden for a long time, until more favorable circumstances arrive.

The bottom line may simply be that cats are only about halfway through the domestication process. They still have one paw in the wild world. Whatever is going on in evolutionary terms, history shows that black cats and people have been through some tough times together, but the bonds of love and friendship between us are still strong, even if we don’t understand what gives these little felines their lovely and very dramatic look.


Featured image: Pedro Ribeiro Simōes. CC BY 2.0.



Sources:
Arendt, J., and Reznick, D. 2008. Convergence and parallelism reconsidered: what have we learned about the genetics of adaptation? Trends in Ecology and Evolution. 23(1): 26-32.

Bashir, T.; Bhattacharya, T.; Poudyal, K.; and Sathyakumar, S. 2011. Notable observations on the melanistic Asiatic Golden cat (Pardofelis temminckii) of Sikkim, India. NeBIO. 2(1): 2-4.

Bradshaw, J. 2013. Cat Sense: How the New Feline Science Can Make You A Better Friend to Your Pet. New York: Basic Books. Retrieved from https://play.google.com/store/books/details?id=iU8PAAAAQBAJ

da Silva, L. G.; Kawanishi, K.; Henschel, P.; Kittle, A.; and others. 2017. Mapping black panthers: Macroecological modeling of melanism in leopards (Panthera pardus). PLOS ONE. 12(4): e0170378. https://doi.org/10.1371/journal.pone.0170378.

Eizirik, E.; Yuhki, N.; Johnson, W. E.; Menotti-Raymond, M.; Hannah, S. S.; and O’Brien, S. J. 2003. Molecular genetics and evolution of melanism in the cat family. Current Biology. 13:448-453.

Graipel, M. E.; Oliveira-Santos, L. G. R.; Goulart, F. V. B.; Tortato, M. A.; and others. 2014. The role of melanism in oncillas on the temporal segregation of nocturnal activity. Brazilian Journal of Biology. 74(3): S142-S145.

Kawanishi, K.; Sunquist, M. E.; Eizirik, E.; Lynam, A. J.; and others. 2010. Near fixation of melanism in leopards of the Malay Peninsula. (Abstract only) Journal of Zoology. 282(3): 201-206.

Kinnear, J. 1983. Feline genetics, in Felis domesticus: A Manual of Feline Health 1982-1983, 121-134. Ithaca: Cornell Feline Health Center.

Lyons, L. 2015. DNA mutations of the cat: The good, the bad and the ugly. Journal of Feline Medicine and Surgery. 17(3):203-219.

Schneider, A.; Henegar, C.; Day, K.; Absher, D.; and others. 2015. Recurrent evolution of melanism in South American felids. PLoS genetics. 11(2): e1004892.

Sunquist, M. and Sunquist, F. 2002. Wild Cats of the World. Chicago and London: University of Chicago Press. Retrieved from https://play.google.com/store/books/details?id=IF8nDwAAQBAJ

Todd, N. B. 1977. Cats and Commerce. Scientific American. 237:100-107.