Ancient Miocene infant ape skull

The complete cranium of a Miocene ape from Africa was found in 2017. It lived before the human lineage split off from the common ancestors we share with chimpanzees some 7 million years ago. Scientists in Kenya found the prize: an almost perfectly preserved skull roughly the size of a baseball from an infant. The remarkably complete skull was discovered in the Turkana Basin of northern Kenya.

Researchers measured argon isotopes—which decay at a fixed, predictable rate—within the fossil’s rock layer, revealing that it was about 13 million years old.

3D animation of the Alesi skull computed from the European Synchrotron Radiation Facility (ESRF) microtomographic data. It shows the skull in solid 3D rendering

X-rays fired at the skull turned up such high-res images of its teeth that the infant's age could be determined to within a matter of months. But the scientists were most excited about its ears. The inner ear structure suggests that it would not have had the balance to perform treetop aerial antics.