Research shows that the wild horses living in North America were most likely wiped out by early humans. Toward the end of the Pleistocene era, the extinction of North American horses, mammoths and other large mammals coincided with the Ice Age. These horses, ancestors of modern donkeys, went extinct in North America, but somehow survived in Africa and Eurasia.
Mastodons are distant relatives of the woolly mammoth. They migrated to North America via the Bering Strait land bridge roughly 15 million years ago. These creatures were prominent in North and Central America until they went extinct 10,500 years ago due to overharvesting by Clovis hunters.
Known as Smilodon, the saber-toothed tiger most commonly lived in North, South and Central America during the Pleistocene epoch. These animals are notable for their large canine teeth that extend from their mouth. The teeth were used to capture and kill prey quickly and could be as long as 1 foot.
Related to modern dragonflies, the Meganeura is the biggest predatory flying insect ever discovered. Its wingspan reaches from 25 to 28 inches. This terrifying insect lived on Earth roughly 300 million years ago. Higher oxygen concentrations in prehistoric times made it possible for this bug to breathe enough to support its size. Luckily, we don’t have to worry about encountering these bugs that are one quarter the size of a human!
