The belief regarding how modern mammals came about has always been linked with the extinction of the dinosaurs. After the giant lizards were allegedly killed by a meteor crash, theorists claim that mammals smashed into the scene and took over the Earth.

A new study, however, seeks to challenge the established theory by attacking the spatial and chronological integrity of the theory. Scientists at the Texas A&M University and the Pennsylvania State University say that there may actually have been three installments on how everything came about after the monumental reptilian wipeout.

Contrary to popular belief, mammals did not diversify in species as a result of enjoying spatial and food opportunities after the dinosaurs vacated the lot. The researchers say that the fossils found closest in date to dinosaurs were unlikely to be the ancestors of modern furry critters. The mammals of that time were dead-ends in terms of evolution and died out in time like dinosaurs.

What actually happened was that a huge number of mammalian species burst into the scene about 85 million years ago, then some more 55 million years ago, then the most likely ancestors 35 million years ago.

The old theory still holds some water, but rather than one huge burst originally claimed, more and more scientists are realizing that the appearance of species took a serious amount of time. The updated family tree has been raised to 4,510 and paleontologists are working on securing more fossils to verify the new study.

You can read more about this exciting new study by clicking the read URL.