Allaeochelys, a transitional form between pond turtles and soft-shell turtles.
A 520 million-year-old fossilised nervous system – so well-preserved that individually fossilised nerves are visible – is the most complete and best example yet found, and could help unravel how the nervous system evolved in early animals - Complete specimen of Chengjiangocaris kunmingensis from the early Cambrian Xiaoshiba biota of South China
This inch long bat is the most primitive bat known (Eocene Green River Fm). Claws on each finger of its wings indicate it was probably an agile climber and crawled along and under tree branches searching for insects.
It took only years to kill more than 90 percent of all life on Earth, according to the most precise study yet of the Permian mass extinction, the greatest die-off in the past 540 million years. Trilobites disappeared during this time.