Octopus brains show surprising similarities with humans | Science

What characterizes the development of human brain cells is that it does not happen where they do their job. Brain cells develop from brain stem cells that, when they grow into functional brain cells, must make another journey to their last place in the brain.

“This particular phenomenon is visible in the brains of vertebrates like humans, but we had no idea if this migration process was important for complex brain formation in general,” says Yves Sentges, professor of evolutionary biology at KU Leuven. “To answer this question, you have to look for an animal with an equally complex brain that is evolutionarily as far from ourselves as possible. Only when there are similarities between animals with a completely different evolutionary starting point does this suggest that this way of brain development is not a coincidence. “.

The eight-armed octopus turns out to be the answer to that question. They have a complex brain structure that they also use usefully. Octopuses are able to play, dream, use things, and even plan ahead. These invertebrates have an entirely different evolutionary starting point that somehow led to the behavior we recognize as humans.

“In the lab, we built an ideal environment in which octopus eggs can develop. Since the eggs are transparent, we were able to closely monitor each stage of development,” says postdoctoral researcher Astrid Dereker. “To our great surprise, brain cells in octopuses exhibit the same migration behavior as human brain cells. This proves that brain cell migration is fundamental to the formation of complex brains.”

Seuntjens concludes that “in the next stage, we’ll try to figure out how you can go from this ingenious structure to effective brain activity and how this then leads to certain behaviors.”