Genes for learning and memory originated 650 million years ago: Study

New Delhi: Genes required for learning, memory, aggression and other complex behaviours originated around 650 million years ago, according to a study published in the journal Nature Communications.

Researchers have known for a long time that monoamines like serotonin, dopamine and adrenaline act as neurotranmitters in the nervous system.

These chemical compounds play a role in complex behavior and functions like learning and memory, as well as processes such as sleep and feeding.

However, the origin of the genes required for the production, detection, and degradation of monoamines is less certain.

"Using the computational methods, we reconstructed the evolutionary history of these genes and show that most of the genes involved in monoamine production, modulation, and reception originated in the bilaterian stem group ," said Roberto Feuda, from the University of Leicester in the UK.

Bilateriaans are a group of animals with bilateral symmetry as an embryo i.e. having a left and a right side that are mirror images of each other.

"This finding has profound implications on the evolutionary origin of complex behaviors such as those modulated by monoamines we observe in humans and other animals," Feuda, who led the study, said in a statement.

This discovery suggests that the monoaminergic system evolved to the Cryogenian/Ediacaran boundary, about 650-600 million years ago, the researchers said.

The researchers suggest that this new way to modulate neuronal circuits might have played a role in the Cambrian Explosion—known as the Big Bang—which gave rise to the largest diversification of life for most major animal groups alive today by providing flexibility of the neural circuits to facilitate the interaction with the environment.

Cambrian explosion, the unparalleled emergence of organisms between 541 and 530 million years ago was characterised by the appearance of many of the major class of organisms (between 20 and 35) that make up modern animal life.

"This discovery will open new important research avenues that will clarify the origin of complex behaviors and if the same neurons modulate reward, addiction, aggression, feeding, and sleep," Feuda added.