IELTS READING S25AT2
What Do Whales Feel?
An examination of the functioning of the senses in cetaceans, the group of mammals comprising whales, dolphins, and porpoises
Some of the senses that we and other terrestrial mammals take for granted are either reduced or absent in cetaceans or fail to function well in water. For example, it appears from their brain structure that toothed species are unable to smell. Baleen species, on the other hand, appear to have some related brain structures but it is not known whether these are functional. It has been speculated that, as the blowholes evolved and migrated to the top of the head, the neural pathways serving sense of smell may have been nearly all sacrificed. Similarly, although at least some cetaceans have Q15 taste buds, the nerves serving these have degenerated or are rudimentary.