Study: Bat Brains Are Structured for Echolocation and Flying

The minds of Egyptian fruit bats are specialized for echolocation and flying, according to a recent research, with motor parts of the cerebral cortex dedicated to sonar generation and wing movement.

Researchers from UC Davis and UC Berkeley published their findings in the journal Current Biology on May 25.

Professor Leah Krubitzer's team at the University of California, Davis Center for Neuroscience investigated how evolution causes diversity in brain architecture in a wide range of animals, including opossums, tree shrews, rodents, and primates.

This cognitive neurobiology method demonstrates how evolution and development both affect brain structure.

Echolocation and flight of Egyptian fruit bats

(Photo : ALEX MITA/AFP via Getty Images)

Despite accounting for a quarter of all extant mammalian species, this is the first time the whole motor cortex of any bat has been mapped, according to first author Andrew Halley, a postdoctoral researcher in Krubitzer's group.

The researchers stimulated different sections of the motor cortex in anesthetized bats with electrodes to determine muscle and limb movements induced by stimulation, as per ScienceDaily.

While traditional theories of motor cortex structure believe that specific muscles are represented in the motor cortex, the current study discovered evidence for complicated motions spanning several body areas.

A bat's wing is made up of membranes that span over its forelimb's "fingers" and back to its hindlimb and tail.

Any of these body elements moving can modify the form of the wing and alter the flight direction.

The researchers discovered that only a few sections of the motor cortex reflected forelimb movement.

The great majority of the cortex, on the other hand, showed synergistic shoulder and hindlimb motions.

This reflects the fact that when these bats fly, shoulder muscles provide the force for wing movement, while synchronized movements of shoulder and hindlimb muscles provide the precise adjustments required for flying.

While forelimb motions were frequently associated with hindlimb movements, other regions of cortex did produce hindlimb muscle movements alone.

These are most likely engaged in the bats' locomotor habits, which include their "walking" about in trees by grabbing branches with their hindlimbs.

According to Krubitzer, studying brain structure in a wide range of animals helps us better comprehend our own brains.

Also Read: Bats Decoded: Fruit Bat Chatter is More Advanced Than You Think

What are Egyptian fruit bats?

Egyptian rousettes are medium-sized bats with dark brown to light gray dorsal fur.

Ventral pelage is many shades lighter than dorsal coloring in both genders, with a collar of pale yellow or orange fur frequently found around the neck, as per Animal Diversity.

There is no color difference between genders. Nonetheless, males have more pronounced stiff hairs down the neck than females.

With the exception of the forehead, where the hair is somewhat longer, short fur covers the entire head almost to the end of the nose.

When compared to the dorsal pelage, ears are around the length of the nose, with blunt points and black color. Egyptian fruit bats have big eyes that are well suited to twilight and night vision.

Egyptian rousettes live in groups varying in size from tiny colonies of 20 to 40 individuals to enormous colonies of 9,000.

Although tiny colonies have been spotted roosting on trees, these colonies prefer to rest throughout the day in dark, slightly damp habitats like cave systems and ruins.

Males and females separate during breeding seasons, with males establishing bachelor groups and females creating maternity colonies.

To lessen the impact of temperature variations, Egyptian rousettes roost in close proximity to other members of the colony.

Close touch among colony members also helps them to communicate with one another throughout the day when roosting.

Egyptian rousettes are more active late in the afternoon and early in the evening when grooming is more frequent.

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