Making Light only recently learned of the existence of pygmy mammoths, Mammuthus exilis, which stood about four feet tall but were in all other respects just like their larger kin. They lived on the Channel Islands, just off the California coast. At the time, the Pleistocene’s lower sea level made what are now four islands into a single larger island (dubbed Santarosae by paleontologists) only fifty miles or so from the mainland; and mammoths, like all the elephant species, were good swimmers.
Once mammoths were on the island, Foster’s Rule kicked in. This is a rule of island adaptation, first proposed by some guy named Foster in 1964, that says that on islands, large continental mammals become smaller and small continental animals become larger. True to form, Pleistocene Santarosae had gigantic deer mice and pygmy mammoths. As L. D. Agenbroad said in a paper on dwarf mammoths:
In the island survey, a ratio of approximately 1:10 large mammoth remains/small mammoth remains was encountered. All of the Columbian mammoth remains, thus far, have been located in elevated marine terrace remnants. Pygmy mammoth remains have been located in marine terraces, alluvial stream terraces, and stream channels near the island uplands. Approximately 50% of the island of Santa Rosa consists of uplands, with slopes exceeding thirty degrees. Using Columbian mammoths of Hot Springs, South Dakota as a representative continental population (Agenbroad 1994), various metric and morphological comparisons were made with the island mammoths. Calculations based on the center of gravity of large and small mammoths revealed that the pygmy mammoths were able to negotiate slopes that were as much as 10 degrees steeper than Columbian mammoths could travel. This suggests one of the reasons that the diminutive forms became the dominant island mammoth population. It should be noted that pygmy mammoths have not been discovered on the continental coast.Pygmy mammoths: ATVs of the Channel Islands.
In 1977, Paul Sondaar, studying stegodons in Indonesia, concluded there was a shortening of lower limb bones, to allow “low gear locomotion” (akin to 4 wheel drive in modern vehicles) needed in ascending and descending steep slopes. This gave smaller animals access to upland pasturage which may have been crucial to survival in periods of climatic or dietary stress. Bone metric analyses confirm Sondaar’s conclusions for M. exilis, the island adapted mammoth. Analyses of the femora, humerii and dentition reveal additional characteristics. … The humerus takes on the added use, as a braking mechanism for a quadruped descending steep slopes.
They survived there far longer than mammoth mammoths did on the mainland, lasting into the Holocene, when the islands were colonized by the Chumash tribes.
It doesn’t end there. Apparently this business of island-dwelling pygmy mammoth populations surviving long after the disappearance of the continental mammoths is something that happened in several places around the world. For instance, Wrangel Island, in the Arctic Ocean off the coast of Siberia, had a population of pygmy mammoths as late as 2000 BCE. These were woollier and a bit bigger than Mammuthus exilis. The question of whether they were fluorescent has not yet been addressed.
Then there’s the matter of a certain wall painting in Thebes, in the 18th Dynasty tomb of Rekh-mi-Re, advisor to Thutmosis III. It shows a procession of Syrian tributaries bringing gifts to the pharaoh. One of them looks like a very small mammoth. Whatever its species, it can’t be a juvenile specimen, because it has long tusks. This is discussed here, in a paper that’s unfortunately available only as a PDF file, if you want to be able to see the illustrations.
This disputed Syrian proboscid is part of the larger phenomenon known as The endemic dwarf elephants of the ancient Mediterranean. They were, too. Here’s a nifty little skeleton from Sicily.
Miniature elephants of the ancient Mediterranean! I don’t know about you , but they certainly change my imagination of the ancient world. They make it funnier. One cannot but regret their disappearance.
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