Human Hunting Evolved as an Adaptated Result of Arboreal Locomotion Model of Two-arm Brachiation

TL;DR

This paper proposes that human hunting behaviors and physical traits evolved primarily as adaptations to two-arm brachiation, enabling effective arboreal locomotion and subsequent hunting strategies.

Contribution

It introduces a novel evolutionary model linking arboreal locomotion to human hunting behaviors and physical adaptations.

Findings

Human body traits are suited for two-arm brachiation.

Adaptive evolution of shoulder bones enhanced arm mobility.

Long thumbs improved hunting accuracy and control.

Abstract

Various fossil evidences show that hunting is one of major means of ancient human to get foods. But the running speed of our ancestors was much slower than quadruped animals, and they did not have sharp claws and canines. So, they have to rely heavily on stone and wooden tools when they hunting or fighting against other predators, which are very different from the hunting behaviors of other carnivores. There are mainly two types of attack and defense action during human hunting, front or side hit with a wooden stick in hands and stone or wooden spears throwing, and throwing had play an important role in human evolution process. But there is almost no work to study the why only human chose to hunting by this way. Here we suppose that ancient human chose two-arm brachiation as main arboreal locomotion mode because of their suitable body weight. Human body traits include slim body, parallel arranged scapulas, long thumb and powerful grip ability are all evolved as results of two arm brachiation. The relevant adaptive evolution of the shoulder bone structure make human arms with a large range of movement and the long thumb makes human activities to be more accurate and controllable. These are two important body structure advantages of ancient human which makes them could get from arboreal life into a whole new hunting and fighting stage.