Researchers from Austria and Sweden have found a link between brain size and immunity. However, while such a regularity is observed only in the guppy fish.
Scientists transplanted the alien fish scales from the other fish and watched as foreign tissue is rejected. Together with the speed of rejection, scientists had information about the size of the brain of each fish.
Less the animal had the brain, the stronger the immune system worked. With reduced immunity scales could not be rejected at all.
It is interesting and different. Among males, the rejection of the scales was significantly faster and brighter. While a single scientific explanation for this phenomenon not. Perhaps initially reduced immunity of females is necessary for the formation of eggs.
The obtained data confirm the theory: the immune system animals with the development of the brain is reduced.