Compared to other primates, human beings are very skilled with the use of their hands. This does not come easy, however. Humans take a much longer time to learn dexterous skills. Babies take up to five months to learn to grip an object. It takes even a longer time or five to six years to learn complicated skills like using a fork or knife. On the other hand, other primates reach this age when they have offspring.
Primate species acquire dexterity at different rates
To better understand how dexterity occurs in primates, Sandra Heldstab, an evolutionary biologist in the Department of Anthropology at the University of Zurich, together with her collogues Carel van Schaik, Caroline Schuppli, and Karin Isler observed 36 primate species for over seven years to determine why human beings take long to learn fine motor skills compared to other primates.
During the study, 128 young animals were observed in 13 European zoos. The primates were observed from birth until the age when they reached adult-level dexterity. The study found that all species followed a specific order when learning their respective manual skills.
“Our results show that the neural development follows extremely rigid patterns—even in primate species that differ greatly in other respects,” says Heldstab.
Large brains needed for high dexterity
The study discovered that there are big differences in the specific fine motor skills of adults from different primates. It was also discovered that the level of dexterity depended on the level of brain of respective primates. The larger the brain, the easier it is to solve complex tasks using hands. This is why chimpanzees, gorillas, and macaques can use their hand more easily than marmosets and lemurs. Human can use their hands on even more complex tasks thanks to their developed brain capacity.
It is not easy to achieve dexterity. For instance, in human beings with large brains, infants take a longer time to learn very simple hand and finger movements. According to Heldstab, this is attributed to the fact that human beings take a longer time to start these skills. They concluded that although humans have larger brains at adult age, their brains are less well developed at birth.