Around 13,000 years ago, giant animals such as mastodons, mammoths, saber-toothed cats and ground sloths disappeared from the Earth. Scientists have found evidence in sediment cores to support a controversial theory that an asteroid or a comet slammed into Earth and helped lead to this extinction of ice age animals and cooling of the globe.
It's called the Younger Dryas Impact Hypothesis and was first suggested in 2007. The hypothesis included the idea that an extraterrestrial body impacted Earth 12,800 years ago. This led to an extreme cooling of the environment, which in turn helped cause more than 35 species of large animals to go extinct.
At the same time, human populations declined. The impact also has been suggested as the cause of large, raging wildfires that created enough smoke to block the sun and created an "impact winter," in which cold weather lasts longer than expected after Earth is impacted.
[...] Today, evidence of such an impact can be found in platinum spikes. Platinum can be found in asteroids, comets and meteorites. Researchers found them in sediment cores collected from White Pond in Elgin, South Carolina.
Sediment Cores from White Pond, South Carolina, contain a Platinum Anomaly, Pyrogenic Carbon Peak, and Coprophilous Spore Decline at 12.8 ka (open, DOI: 10.1038/s41598-019-51552-8) (DX)
(Score: 2) by ChrisMaple on Thursday October 31 2019, @05:29AM
Smilodon (saber tooth cat) went extinct 10,000 years ago. The woolly mammoth went extinct 4000 years ago.
The largest smilodon was probably a bit smaller than the largest modern wild tiger, and so doesn't qualify as "giant".