GOOD MORNING!
Today's paper is an old one (for neuro, at least) hailing from 1979. The authors explored the visual system in the brains of echolocating and non-echolocating bats-- if you didn't know that some bats don't echolocate, now you do.
They tried a couple different methods, including removing one eye and looking for the destruction of downstream neurons and injecting the eye with an early form of anterograde tracers (psst: these are just chemicals that travel down neurons the same way information does, depositing chemical along the way, so you can see what neurons are connected).
They found that, generally, the echolocating bats had a "less developed" visual processing pathway. Some areas were smaller, some seemed less connected to the eye, and some didn't have the cellular complexity of the same areas in non-echolocating bats. This all makes sense: a bat that navigates more with sound doesn't need to process visual information as thoroughly. Better to leave more of the brain for hearing.
Just for fun, here is one of the echolocating bats (Myotis lucifugus, or little brown bat, photo from Bat Conservation International):
And here is one of the non-echolocating bats (in the paper it is called Pteropus giganteus, but the modern nomenclature is Pteropus medius; regardless, it's an Indian flying fox and I got this photo from Wikipedia):
Thanks for appreciating bats with me today!
Cotter, J.R., & Pentney, R.J.P. (1979). Retinofugal projections of nonecholocating (Pteropus giganteus) and echolocating (Myotis lucifugus) bats. J. Comp. Neuro. 184: 381-400.












