Ice layer dating
One of the richest sources of information about life in the Pleistocene Epoch can be found in the La Brea Tar Pits in Los Angeles, where remains of everything from insects to plant life to animals were preserved, including a partial skeleton of a female human and a nearly complete woolly mammoth.
In addition to the woolly mammoth, mammals such as saber-toothed cats (Smilodon), giant ground sloths (Megatherium) and mastodons roamed the Earth during this period.
Other than a few birds that were classified as dinosaurs, most notably the Titanis, there were no dinosaurs during the Pleistocene Epoch.
They had become extinct at the end of the Cretaceous Period, more than 60 million years before the Pleistocene Epoch began.
Geologists use a dating technique called K-Ar geochronology to find the age of layers of volcanic ash in ice cores. By measuring the ratio of K to Ar in feldspar crystals in volcanic ash, geologists can determine the time of the eruption and, thus, the age of ice in which the ash is found. Heating causes the kernels to begin popping, thereby starting your simulated “radioactive decay clock” and producing popped “daughter” popcorns.Never before has a species on earth farmed crops and lived settled sedentary lives. These are the foundations of modern human civilization. The flightless birds did not fare as well, as they had to compete with mammals and other creatures for limited supplies of food and water, as a good portion of the water was frozen.
Crocodiles, lizards, turtles, pythons and other reptiles also thrived during this period.
During this period, British geologist Edward Forbes aligned the period with other known ice ages.