Biologists have discovered why octopuses see as well as vertebrates, Current Biology reported.

Traditionally, vertebrates are considered the most developed and evolutionary "advanced" creatures, but on many parameters, such as intelligence and dexterity, octopus and cuttlefish are not inferior to them. They have complex brains and nervous systems, and cephalopod tentacles have their own nervous system.

Christopher Neill of Oregon State University in Eugene and his colleagues bought several young Octopus bimaculoides and monitored the activity of their nervous system-related genes. Primarily, the scientists were interested in the structure of nerve cells related to vision. In total, the researchers obtained data on gene activity in 26,000 cells extracted from different regions. The analysis showed that there are six large subclasses of nerve cells in the optic lobe of the octopus brain, which produces different chemical signals and differ markedly from each other in shape, structure, and level of activity. The nature of the interactions between these cells, as well as the structure of the connections between them, were completely different from the way the visual regions of the human and other mammalian cortexes are arranged.

In addition, the scientists found that approximately one-third of the nerve cells in the visual lobe of the octopus brain are immature. This suggests that the structure of this region of the cephalopod's nervous system is constantly changing and becoming more complex as these neurons mature and grow.

In the future, the researchers want to try to turn off or forcefully activate certain genes and track the effects of these factors on the clams' vision and behavior.