Whales are diverse marine mammals inhabiting the world’s oceans, exhibiting a wide range of sizes, behaviors, and adaptations. One notable distinction among whale species lies in their feeding apparatus. Some whales possess teeth for capturing prey, while others have specialized structures for filter feeding.
Toothed Whales
The suborder Odontoceti encompasses all whales that possess teeth, including dolphins, porpoises, and larger whales. Over sixty species exist within this diverse suborder, ranging from the small vaquita to the enormous sperm whale. All members use their teeth primarily for catching and holding prey, rather than for chewing.
The number, size, and shape of teeth vary significantly among toothed whale species, reflecting their varied diets. For instance, dolphins typically have 72 to 104 sharp, pointed teeth used to snatch fish, crabs, shrimp, and squid, which they usually swallow whole. Orcas, also known as killer whales, possess 40 to 56 robust, conical teeth, each up to 4 inches long, that interlock and are designed for gripping and tearing prey. Sperm whales, the largest toothed whales, have 36 to 60 conical teeth located primarily on their lower jaw, which fit into sockets in their upper jaw.
Baleen Whales
In contrast to toothed whales, the suborder Mysticeti, known as baleen whales, do not possess teeth. Instead, these whales have baleen plates: large, flexible, keratinous structures that hang from their upper jaws. Baleen is made from the same protein found in human fingernails and hair. These plates function as a filter-feeding system, allowing baleen whales to strain vast quantities of small organisms from the water.
To feed, a baleen whale takes in a massive mouthful of water and prey, then pushes the water out through the baleen plates, trapping food inside. Prominent examples of baleen whales include the blue whale, the largest animal on Earth, humpback whales, and gray whales. There are 16 recognized species of baleen whales, which generally tend to be larger than toothed whales.
Dental Adaptations and Feeding Strategies
The presence or absence of teeth dictates vastly different feeding strategies among whale species. Toothed whales are generally predators that actively hunt individual prey items. Their teeth are adapted for capturing a range of prey, from fish and squid to marine mammals. For example, the conical, interlocking teeth of orcas are highly effective for grasping and tearing the flesh of seals, other marine mammals, and fish.
Sperm whales, which primarily consume deep-sea squid, utilize their teeth to grip and hold their prey, often swallowing it whole. In contrast, baleen whales are obligate filter feeders, relying on their baleen to strain small organisms like krill, copepods, and zooplankton from seawater. Different baleen whale species employ distinct filter-feeding methods, such as gulp feeding, where they engulf large volumes of water and prey, or skim feeding, where they swim with open mouths through dense patches of food. Gray whales, for instance, are known to be bottom feeders, sifting through sand to filter out benthic creatures.