Extinct Organisms You Should Know About

Ever since the oceans formed more than 3.8 billion years ago, countless organisms have come and gone since then. In fact, of all the species that ever existed on earth, 99.9 percent are now considered extinct. Some of these organisms were unlike anything that humans have ever seen. In this article, we shall take a closer look at some of the more intriguing organisms to have lived on this planet. 


The thylacine was a large, carnivorous marsupial, once believed to have roamed all over Australia. However, its habitat dwindled and was confined to the island of Tasmania, off the coast of Australia. What makes the thylacine special is that it was the only member of the Thylacinidae family that survived into the modern times. At first glance, the animal’s head looks similar to a dogs, but its body has distinct, dark stripes running from its shoulders to its tail. Like other marsupials, female thylacines had a pouch which was used to carry its young. However, it was a back-opening pouch which was also present on the males. This species was officially declared extinct in 1936, after the last known specimen died at a Zoo in Hobart, Tasmania.

Woolly Mammoth

The woolly mammoth was an elephant-like mammal that lived across Europe, Asia, North America and even Africa. It was also the last in a line of elephants that evolved to have thick hair and long earlobes. In real life, the wooly mammoth would have been a sight to behold – it is thought to have been around 10 feet tall and weighed over 3 tons. Among its various types of teeth, its incisors (also called tusks) are the most impressive. It was more curved than modern elephants and averaged between 7.9–8.9 ft in length. The woolly mammoth went extinct about 10,000 years ago, however, the exact cause of their extinction was unclear. Scientists have speculated many causes – from climate change and viral pathogens to habitat destruction and over-hunting by humans. However, evidence suggests that the extinction of these giants were accelerated by the latter. The woolly mammoths had been hunted for their meat, fur, fat, tusk and bones. This was because food was rather scarce and the only other form of sustenance came from these animals. Parts of the mammoth were also used to make tools, weapons and other artifacts.


Leedsichthys is a genus of giant bony fish from the Jurassic period. It is believed that they were one of the largest, if not the largest, ray-finned fish to ever live. The fish was over 50 feet long and had an estimated weight of 40-45 metric tons. Though it was massive, it was a filter feeder, which fed by swimming through the water with their mouths open, much like today’s basking sharks and whale sharks. However, scientists are not completely sure what this animal looked like because of the fact that many parts of this animal did not fully fossilize. This giant was thought to have become extinct due to climate change and a decrease in the plankton populations.

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