Most of the animals shown here existed during the Pleistocene, otherwise known as Ice Age era, which lasted from around 2.58 million to 11m7 thousand years ago. As the term Ice Age signifies, it was a glacial period where most of the northern hemisphere was covered in, you guessed it, ice. The glaciations happened on and off in steady cycles which lasted from 41,000 to 100,000 years.

As you probably know by now, all of the ancestor species shown here are extinct. Almost all, if not all of these species went extinct in the so-called Quaternary period (2.58 million years before the present) in the Late Pleistocene. This period is marked by numerous megafaunal and other extinctions. This pulse extinction is characterized by the fact that there was a widespread absence of ecological successors, which caused a major shift in faunal habitats and relationships.

Fact: life on Earth has suffered 5 major extinction events, and is going through one so-called Holocene extinction event right now. An extinction event is a widespread and rapid decrease in biodiversity. The greatest extinction event killed 90 to 96 per cent of all species. Scientists argue over the exact number of extinction events life has gone through, ranging from five to as many as twenty. The current extinction event is different from others because human activity plays a huge hand in it.

Let's hope you learned something new today. If you didn't, or if you're up to learn even more cool stuff, Bored Panda is here to help you satisfy this thirst for knowledge. Here's our latest edition of "Today I Learned" posts that our community loves. Too general, want to learn something more animal-centric? No problem. Want to know more about silly bird names that ornithologists came up with? Or perhaps you want to know what insects really look like when they're flying? Let's not end this post about extinct species with a sad note: here's a story about reappeared elephant shrew species that we thought went extinct 50 years ago.

Roman shared: "My favorite animal is the one I’m drawing right now. So every time I get a new favorite. Can you imagine that ancient rodents were the size of a rhinoceros, and extinct rhinos led the life of giraffes and were the tallest animals in the world?!"

"My wife and business partner Alexandra Antonova (Uchytel) is a great writer. She has so many cool ideas. Now we’re working on one idea—Prehistories (a series of prehistoric fairy tales). Now all we have to do is find a publisher."