Excerpts:
“A bird with a 10-gram brain is doing pretty much the same as a chimp with a 400-gram brain,” said Onur Güntürkün (opens a new tab), who studies brain structures at Ruhr University Bochum in Germany. “How is it possible?”
In mammals, brain development follows an intuitive path: The cells in the embryo’s amygdala region at the start of development end up in the adult amygdala. The cells in the embryo’s cortex region end up in the adult cortex. But in birds, “there is a fantastic reorganization of the forebrain,” Güntürkün said, that is “nothing that we had expected.”
Taken together, the studies (Evolutionary convergence of sensory circuits in the pallium of amniotes on the one hand, Constrained roads to complex brains and Developmental origins and evolution of pallial cell types and structures in birds on the other hand, Ed.) provide the clearest evidence yet that birds and mammals independently evolved brain regions for complex cognition. They also echo previous research from Tosches’ lab, which found that the mammalian neocortex evolved independently from the reptile DVR (dorsal ventricular ridge).
Still, it seems likely there was some inheritance from a common ancestor. In a third study that used deep learning, Kempynck and his co-author Nikolai Hecker found that mice, chickens and humans share some stretches of DNA (opens a new tab) that influence the development of the neocortex or DVR, suggesting that similar genetic tools are at work in both types of animals. And as previous studies had suggested, the research groups found that inhibitory neurons, or those that silence and modulate neural signals, were conserved across birds and mammals.
Such findings could eventually reveal shared features of various intelligences, Zaremba said. What are the building blocks of a brain that can think critically, use tools or form abstract ideas? That understanding could help in the search for extraterrestrial intelligence — and help improve our artificial intelligence. For example, the way we currently think about using insights from evolution to improve AI is very anthropocentric. “I would be really curious to see if we can build like artificial intelligence from a bird perspective,” Kempynck said. “How does a bird think? Can we mimic that?”