
The zebra finch is one of the clever birds analysed in the study.
Scientists studied the number of neurons held in the brains of small birds and discovered that actually there are many clever birds out there. The size of the brain was compensated by local connections and smaller neuron size.
There were more than 20 birds involved in the study, including the zebra finch, the macaw, and the emu. Scientists were interested in how such a small brain as the one of a bird can perform complex cognitive behaviors.
The results showed that in general, birds have more neurons than mammals. However, parrots and songbirds can have twice the number of neurons that can be found in primate brains.
Researchers used an isotropic fractionator to measure the number of neurons in certain areas of the brain. When comparing the data with previous similar studies in mammals, they discovered that avian birds have a higher density of neurons in their brains than the mammalian ones.
Corvids and parrots have even more neurons in the pallial telencephalon, a brain area that is responsible for emotions, hearing, and vision. The authors believe that this concentration of neurons is the foundation for avian intelligence.
Scientists say that nature has two available possibilities when designing brains. On one hand there is the size and the number of neurons, and on the other hand there is the distribution of neurons in the brain centers.
The neurons could help birds have better motor skills and sensory abilities. However, there is no proof that a higher percentage of neurons can support functions like reasoning or planning.
The connection between the number of neurons and intelligence has not been scientifically proven. The classical theory said that having a large brain could foster knowledge. This is not the case with the tiny bird brains that are loaded with neurons and can perform actions related to complex behaviors.
The birds’ neurons are smaller in size, and many of them are connected locally. Only a limited number of neurons are allowed to grow and to get connected on long distances.
The present study shows that brains can have different structures which may be allowing even small-sized creatures to be very smart.
Scientists even wonder if there is a connection between the large number of neurons, the flight activity and the amount of food needed by such clever birds. The small size of the body could be explained by the fact that a lot of the food intake is used by the brain. Moreover, the complexity of the flight consumes another vast amount of calories.
Image Source: Pixabay