Researchers have put together some data gathered from the study of a dozen complete skeletons and announced the discovery of a tree-climbing mammal that used elongated fingers and opposable "thumbs" to climb trees and get away from predators.
The skeletons were found nearly twenty years ago in Russia, in a large block of mudstone that dated back to the Late Paleozoic, about 30 million years before dinosaurs took over the planet. The mammal is known as Suminia getmanovi.
The skeletons are those of both boys and men, giving scientists a look at how the Suminia skeleton developed over time. The fact that they were buried together in the one block of stone implies they were social animals.