Even though humans are genetically similar to chimpanzees and bonobos, there are evident differences regarding behavior and cognitive functions. What makes us human and how our brains evolved to rich to this point? To these questions, among others, the researchers from the Salk Institute and the anthropology department at UC San Diego tried to answer. To do that, they shed more light on the brain evolution in humans and the early development of human neurons in comparison with those in primates.
“This study provides insights into the developmental organization of the brain and lays the groundwork for further comparative analyses between humans and nonhuman primates,” explained Rusty Gage, the leading author of the study and the President of Salk Institute.
According to scientists, there are two crucial processes in brain development – neurons maturation and neurons migration. The first one refers to the growth of neural cells and the increase in the connections between neurons for better communication between each other. Neurons migration for its part involves the movement of neural cells in specific regions of the brain during its development.
Scientists Shed More Light On The Brain Evolution In Humans
To find out more about the brain evolutions in humans, the scientists decided to compare both neurons maturation and migration processes in humans with those in primates.
“This is a novel strategy to study human evolution. We are happy to share these primate cell lines with the scientific community so that researchers from around the world can examine primate brain development without the use of tissue samples. We anticipate this will lead to numerous new findings over the next few years about the brain’s evolution,” said Carol Marchetto from the Salk Institute.
The researchers identified 52 genes involved in neurons migration. Chimpanzees and bonobos showed rapid periods of neural cells migration, while humans presented much slower neurons movements. On the other hand, neurons in the human brain reach a higher length in comparison to neural cells in chimpanzees and bonobos. That, along with the slower neurons migration, might have had a significant role in the brain evolution in humans and in making us what we are today since that may have allowed us to reach many milestones in our evolutionary path.
“We have limited knowledge about the evolution of the brain, especially when it comes to differences in cellular development between species. We’re excited about the tremendous possibilities this work opens up for the field of neuroscience and brain evolution,” concluded Marchetto.