Megabat evolved early in the lineage of chiropterans. Although echolocation was later lost in family Pteropodidae, bats in the genus "Rousettus" are capable of primitive echolocation through clicking their tongues, and some species have been shown to create clicks similar to those of echolocating bats using their wings. Both echolocation and flight are energetically expensive processes. The nature of the flight and echolocation mechanism of bats allows for creation of echolocation pulses with minimal energy use. Energetic coupling of these two processes is thought to have allowed for both energetically expensive processes to evolve in bats. The loss of echolocation may
What Is it Like to Be a Bat? is connected with a "single point of view", making it unfeasible to consider any conscious experience as "objective". Nagel uses the metaphor of bats to clarify the distinction between subjective and objective concepts. Bats are mammals, so they are assumed to have conscious experience. Nagel used bats for his argument because of their highly evolved and active use of a biological sensory apparatus that is significantly different from that of many other organisms. Bats use echolocation to navigate and perceive objects. This method of perception is similar to the human sense of vision. Both sonar and vision are regarded as