Pictured above is a recreation of Smilodon fatalis, the species of saber-toothed cat that is the mascot of the Page Museum in Los Angeles. At one time, several species of sabercat roamed North America, but they disappeared along with the other big extinct mammals whose bones are found in the La Brea tar pits. Not fossils -millions of actual bones that have been preserved for thousands of years in asphalt.
Familiar or alien, all these creatures — and many others — disappeared from North America between 50,000 and 8,000 years ago. On a human scale, this seems a long time, but in the fossil record it marks a calamitous, rapid decline. Paleontologists and archaeologists have invoked many possible causes for the catastrophe, from disease and a wayward comet to climate change and hungry, hungry humans. Today, only the latter two mechanisms are taken seriously, but exactly how the dispersal of humans conspired with the onset of a warmer, wetter global climate to drive so many species to extinction is still fiercely debated. Figuring out how the disaster played out is critical to understanding the future of life on Earth. This was not a just a last stand of Ice Age animals against the beginning of the Anthropocene, or age of humans. The extinction of the megamammals is part of a drawn-out process that continues to tatter and imperil what’s left of the planet’s wilderness.
Most scientists have believed that, as the mammoths, horses and bison of the Ice Age disappeared — whether killed by humans in need of meat, by habitat loss, or by a combination of factors — the abundant populations of Smilodon simply ran out of food on the hoof. Jaguars, grey wolves and other carnivores survived, but North America’s last sabercat apparently could not cope with the changes that arrived at the close of the Pleistocene.
Research in the tar pits has shifted from finding the largest and weirdest animals 100 years ago to preserving all the evidence of prehistoric creatures, no matter how small, in order to build a more complete picture of the ancient environment that may give us more clues as to why Smilodon is no longer with us. Aeon magazine has an article about the sabercats and what we know about them, including how our knowledge of them has changed over the past few decades. -via Not Exactly Rocket Science
(Image credit: Sergiodlarosa)