Miocene

According to the researchers, who discovered a skull of the beast in a Peruvian desert, the creature lived 13 million years ago and preyed and dined on other whales.

Going further back, it turns out we share a common ancestor with all large primates about 13 million years ago. Even further back is found a common ancestor with all placental mammals about 60 million to 80 million years ago.

We learn the Pleistocene began 13 million years ago (reality 1.8.5 MYR).

So when the water of the Miocene Sea, in southern Poland, evaporated just over 13 million years ago, the salt it left behind was a treasure that eventually provided a succession of the country's kings with a third of their income in the Middle Ages.

Although they first appeared in Eurasia some 13 million years ago, the animals we know as elk first entered North America by crossing the Bering land bridge between Asia and Alaska about 120,000 years ago.

After analyzing crystals excavated from an ancient South American streambed, researchers report in the April 10 Science that this continental connection must have taken place before 13 million years ago. Although not all experts are convinced, the researchers argue that the unearthed crystals originated in Panama and flowed down a river that straddled both continents.

Around 5 to 13 million years ago, oceans were warmer than they are today -- even though atmospheric carbon dioxide concentrations were considerably low.

If the human and chimp mutation rates remained constant throughout evolutionary history, the species would have shared their most recent common ancestor about 13 million years ago.

He said that the result also explains the lack of fossil record for the echidna before 13 million years ago.

coli lost that trait more than 13 million years ago, so when bacteria in one flask--designated Ara-3 (shown below)--started gorging on the chemical, scientists were fascinated.