Channel Islands Dwarf Mammoth

To be absolutely clear: the Channel Islands Dwarf Mammoth has not lived and died on the European Channel Islands, situated between England en France in the English Channel or la Manche, depending on which coast you're standing.
The Channel Islands (or ArchipiƩlago del Norte) we're talking about is an archipelago consisting of eight islands in the Pacific Ocean, off the coast of Southern California. On some of these islands (Santa Cruz, Santa Rosa and San Miguel) remains have been found since 1856 of the Channel Islands Dwarf Mammoth (Mammuthus exilis). It is thought that this species of dwarf elephant descended from its larger family member, the Columbian Mammoth (Mammuthus columbi) of mainland North America[1].

The Channel Islands Dwarf Mammoth became extinct during the Quaternary extinction event (of still largely uncertain causes) in which many megafauna species disappeared from the face of the earth due to changing conditions to which these species could not sufficiently adapt.

From a recent analysis in 2010 it was determined that the Channel Islands Dwarf Mammoth was on average, 1.70 meters tall at the shoulders and weighed around 750 kilograms.

The Channel Islands Dwarf Mammoth appears to have survived on the islands until the arrival of the humans around 13,000 years ago as the last known mammoth occurrence was around the same time.

Since modern elephants are excellent swimmers, the ancestors of the Channel Islands Dwarf Mammoth could probably swim the six kilometers from the coast to the island of Santa Rosa. As the population of mammoths increased, the lack of large predators and the loss of habitat caused by the rise of sea levels at the end of the ice age. As a result, Santa Rosae split into four islands favoured smaller animals. Because of this, the Dwarf Mammoth began to evolve through generations as a survival mechanism to stay alive on the ever-shrinking Santa Rosa Island; their body size became smaller because it required less food and resources to remain energized and alive. The mammoth had become a distinct species, the Channel Islands Dwarf Mammoth.

[1] Agenbroad, Morris: Giant Island/Pigmy Mammoths: The Late Pleistocene History of Channel Islands National Park. See here.

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