KNM-KP 29285

KNM-KP 29285
Exhibit item
Kanapoi, Kenya
Date of discovery: 
Discovered by: 
Kamoya Kimeu
About 4.1 million years old

Walking upright on shorter legs

This 4.1 million year old upper tibia (shin bone) fossil, KNM-KP 29285 from Kanapoi, Kenya, comes from an early human species that lived near open areas and dense woods; Australopithecus anamensis. Their bodies had evolved in ways that enabled them to walk upright most of the time, but still climb trees. As a result, they could take advantage of both habitats. The top part of the tibia where the lower leg meets the knee is concave, or depressed from stress. This shows that the individual often put weight on the bone—evidence of standing upright. The lower part of the tibia where the lower leg meets the ankle is wider or thicker—evidence that it acted as a type of shock absorber as this individual walked .



Image of KNM-KP 29285, tibia