Megabat long, thus smaller than some microbats, for example, the Mauritian tomb bat. The largest attain a wingspan of , and weigh as much as . Most fruit bats have large eyes, allowing them to orient themselves visually in twilight and inside caves and forests. Their sense of smell is excellent. In contrast to the microbats, the fruit bats do not use echolocation (with one exception, the Egyptian fruit bat "Rousettus egyptiacus", which uses high-pitched tongue clicks to navigate in caves). Megabats make up the only family (Pteropodidae) in order Chiroptera that is not capable of laryngeal echolocation. Echolocation and flight
Lazzaro Spallanzani with frogs, and an artificial insemination, using a dog. Spallanzani showed that some animals, especially newts, can regenerate some parts of their body if injured or surgically removed. Spallanzani is also credited with the classification of tardigrades, which are one of the most durable extremophiles still to this day. (See Binomial Nomenclature) Spallanzani is also famous for extensive experiments on the navigation in complete darkness by bats, where he concluded that bats do not use their eyes for navigation in total darkness, but some other sense (see animal echolocation). He was the pioneer of the original study of echolocation, though