Table 1.
Derived features of the human skeleton with functions adapted for running.
| Feature | Functional role | Earliest evidence |
|---|---|---|
| More balanced head, short snout | Head stabilization | H. habilis |
| Tall, narrow body form | Thermoregulation | H. erectus |
| Forearm shortening, narrow thorax | Counterrotation of trunk | H. erectus |
| Narrow pelvis | Counterrotation of trunk vs. hips | Homo? |
| Stabilized sacroiliac joint | Trunk stabilization | H. erectus |
| Long legs | Stride length | H. erectus |
| Shorter femoral neck | Stress reduction | H. sapiens |
| Long achilles tendon, plantar arch | Energy storage | Homo? |
| Permanently adducted hallux | Stability during plantar flexion | H. habilis |
| Short toes | Stability during plantar flexion | H. habilis |
| Distal mass reduction |