A behavioural framework for the evolution of feeding in predatory aquatic mammals

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 284; no. 1850; p. 20162750
• Main Authors: Hocking, David P., Marx, Felix G., Park, Travis, Fitzgerald, Erich M. G., Evans, Alistair R.
• Format: Journal Article
• Language: English
• Published: England The Royal Society 15.03.2017; The Royal Society Publishing
• Edition: Royal Society (Great Britain)
• Subjects: Animals; Aquatic ecosystems; Aquatic mammals; Biological Evolution; Caniformia - physiology; Cetacea; Ecosystem; Evolution; Feeding; Feeding Behavior; Foraging; Mammals; Marine Mammal; Pinnipedia; Predators; Predatory Behavior; Prey; Prey Handling; Processing; Review; Secondarily Aquatic; Swallowing; Water Removal; Whales - physiology; foraging; processing; secondarily aquatic; prey handling; marine mammal; water removal
• ISSN: 0962-8452; 1471-2954; 1471-2954
• DOI: 10.1098/rspb.2016.2750

Extant aquatic mammals are a key component of aquatic ecosystems. Their morphology, ecological role and behaviour are, to a large extent, shaped by their feeding ecology. Nevertheless, the nature of this crucial aspect of their biology is often oversimplified and, consequently, misinterpreted. Here, we introduce a new framework that categorizes the feeding cycle of predatory aquatic mammals into four distinct functional stages (prey capture, manipulation and processing, water removal and swallowing), and details the feeding behaviours that can be employed at each stage. Based on this comprehensive scheme, we propose that the feeding strategies of living aquatic mammals form an evolutionary sequence that recalls the land-to-water transition of their ancestors. Our new conception helps to explain and predict the origin of particular feeding styles, such as baleen-assisted filter feeding in whales and raptorial ‘pierce’ feeding in pinnipeds, and informs the structure of present and past ecosystems.