Which of the following features is common in all primates according to anthropological studies?

The common feature noted in all primates is their adaptation for climbing. This evolutionary trait is significant because primates, including both prosimians (like lemurs), monkeys, and apes, have adaptations such as flexible limbs, grasping hands and feet, and enhanced balance for navigating arboreal environments. These physical characteristics have enabled them to thrive in trees, where many primates primarily live and find food.

This inherently arboreal lifestyle has shaped various physiological traits across the primate lineage, even among species that may not primarily inhabit trees today. For example, the flexible shoulder joint allows for a wide range of motion, critical for climbing. While some other features mentioned could be present in specific groups of primates, adaptation for climbing is a distinguishing characteristic that all primates share.