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
Hourglass dolphin dolphin does not have a dorsal fin, so the two species are easily distinguished. The fin considerably varies across individuals. It is generally tall and curved, and the curve may be particularly pronounced in older animals. A fully grown adult is about length and weighs . Males are thought to be slightly smaller and lighter than females, although the small number of specimens does not permit a firm conclusion. Like all species of dolphin, they use echolocation to find food and communicate with other members of the their pod. The range is circumpolar from close to the Antarctic ice pack