Cetacean Brain Evolution
Cetaceans (whales, dolphins and porpoises) are a group of aquatic mammals consisting of baleen whales and toothed whales. While the brain size relative to body size of the earliest cetaceans was not particularly large, this significantly increased in toothed whales around 34 million years ago. The i...
| Main Author: | |
|---|---|
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
University of Liverpool
2022
|
| Subjects: | |
| Online Access: | http://livrepository.liverpool.ac.uk/3150607/ https://static1.squarespace.com/static/5ab572d9ec4eb7e76ad1eabd/t/6287c653fa2c595831231317/1653065302598/II_Issue5_Warren.pdf http://livrepository.liverpool.ac.uk/3150607/1/II_Issue5_Warren.pdf |
| Summary: | Cetaceans (whales, dolphins and porpoises) are a group of aquatic mammals consisting of baleen whales and toothed whales. While the brain size relative to body size of the earliest cetaceans was not particularly large, this significantly increased in toothed whales around 34 million years ago. The increase in relative brain size involved a considerable decrease in body size and a more modest increase in absolute brain size. Nowadays, the relative brain size of cetaceans is exceptionally large; in some toothed whales this is second only to humans. A significant amount of energy is required to grow and maintain such large brains, so why have they evolved? This question has sparked considerable debate among researchers. Several drivers of cetacean brain enlargement have been suggested, including a need to cope with social and/or environmental challenges. Other researchers suggest that a global decline in oceanic temperatures during cetacean evolution drove their brain expansion. However, this hypothesis has received considerable criticism. As well as the drivers of their brain enlargement, fascination surrounds the cognitive abilities and behaviours such brains may engender for cetaceans, among both researchers and the general public. Studying such behaviours has wider implications for how intelligent these animals are perceived to be, which has challenged traditional views of the intellectual status of non-human animals. |
|---|