Ultrasonic propagation properties of mammalian testes.

Unfortunately, only a limited amount of information exists regarding this sensory capability in other marine mammals. Evans, n in a review of the literature, reports comparative discrimination performance, in an echolocation task, for the Bottlenose porpoise (T•rsiops trueearns) and for the Amazon-River dolphin (lnia geoffrenisis) using submerged targets of varying reflective signal strengths. Inspection of this data suggests that both delphinids could detect (at 70% correct responses) a reflective signal difference of about 1.0 dB. One should expect both Tursiops and Inia to exhibit a smaller DL for intensity than the sea lion since both species are known to possess a sophisticated echolocation system.