Prosimians turned to the foliage cover of dense forests to seek protection from predators and occasional flooding. Europolemur kelleri, which was about as big as a domestic cat, used all four of its extremities to climb and jump among the trees. Other species of prosimians found at Messel only reached half that size. Contrary to the prehistoric horses, nothing is known about the prosimians’ reproductive biology; however, it can be assumed that they produced one to two offspring a year, similar to the modern-day lemurs.