What is the oldest animal species in the world?

Earth is an exciting and ever-changing place, and everything from the temperature of the oceans to the amount of oxygen in the atmosphere is constantly changing. And in this world of change Which animal survived the longest?

In November 2010, Guinness World Records awarded the title “oldest living creature” a Triops cancriformis, or tadpole shrimp. Fossils show that these armored shrimp-like crustaceans have existed since the Triassic period (251.9 to 201.3 million years ago).

Tadpole shrimp have paddle-like bodies, perfect for burrowing at the bottom of the temporary pools they inhabit. The design works so well that they have maintained it for hundreds of millions of years.

However, Although they look the same as they always have, DNA research published since 2010 reveals that tadpoles have never stopped evolving beneath its armor, creating differences between species over time that human eyes can’t always detect.

The tadpole shrimp: an antecedent of millennial life

The shrimp tadpole T. cancriformis is simply a descendant of similar-looking Triassic ancestors and is actually no more than 25 million years old, according to a 2013 study published in the journal PeerJ, and could be up to 2.6 million years old, according to a 2012 study published in the journal PLOS One.

However, there are several species alive today that, like tadpoles, appear to have remained unchanged for many millions of years. Perhaps the most famous of the so-called “living fossils” is a group of deep-sea fish called coelacanths.

Researchers discovered coelacanth fossils in the 19th century and thought they were extinct at the end of the Cretaceous, 66 million years ago. But in 1938, fishermen found a live coelacanth off the coast of South Africa. These ancient fish date back more than 400 million years, but they have a trick.

The coelacanth species that swim in the oceans today are not the same fossilized coelacanth species, which actually went extinct.. A 2010 study published in the journal Marine Biology suggests that living species arose within the last 20-30 million years.

The same can be said for the equally ancient lineage of the horseshoe crab, dating back some 480 million years. According to a 2012 study published in the journal Molecular Phylogenetics and Evolution, the oldest group of Asian horseshoe crabs, called Tachypleus, appeared about 25 million years ago, despite their resemblance to fossils hundreds of millions of years old.

the oldest creatures

Biologists aren’t done deciphering the evolutionary history of all living animals yet, and there won’t be a definitive answer to this mystery until they do. Yet tadpoles, coelacanths and horseshoe crabs tell us that even the seemingly most stable organisms are constantly changing.

“I don’t think there is any evidence that a single species has existed for more than a few million years.said Africa Gomez, an evolutionary biologist at the University of Hull and lead author of the 2013 tadpole shrimp study.

Studies of the fossil record suggest that species typically last between 500,000 and 3 million years before succumbing to extinction or being replaced by a descendant.according to an article in American Scientist magazine.