The specialized language used to describe animal families often includes unique terms for their young. While many people associate the word “calf” primarily with young domestic cattle, this term is applied across a much broader range of species. The application of “calf” generally signals specific biological characteristics shared by the offspring of certain large mammals. This article explores the zoological context of the term and identifies the terrestrial and marine animals whose young are designated as calves.
The Defining Characteristics of a Calf
The use of the term “calf” in zoology extends beyond bovine species to describe the young of various large, mostly herbivorous mammals. A defining characteristic of these young animals is their precocial nature, meaning they are relatively mature and mobile from the moment of birth. This high degree of development allows a calf to stand and often walk shortly after delivery, a necessity for survival in herd animals that must quickly evade predators.
The term is typically reserved for the offspring of species whose adult females are often referred to as “cows,” and adult males as “bulls.” This naming convention is applied to both ungulates, or hoofed mammals, and certain large non-ungulate species. This ability to stand within minutes to hours after birth contrasts sharply with the altricial young of other mammals, which are born helpless and require extended parental care.
Terrestrial Animals Called Calves
The most recognized use of the term is for the young of domestic cattle (Bos taurus), which can weigh between 25 and 45 kilograms at birth and stand within their first hour of life. This naming convention extends to other members of the Bovidae family, including bison, yaks, and water buffalo, all of which produce precocial calves.
The term is also used for the young of the largest terrestrial mammals, the pachyderms. An elephant calf is born weighing over 100 kilograms and remains dependent on its mother and herd for years. Similarly, the young of rhinoceroses and hippopotamuses are called calves, reflecting their massive size and the cow/bull designation of their parents. Other large grazing or browsing animals, such as moose, elk, and various species of deer, also have young referred to as calves, as do members of the camelid family, including camels and llamas.
Marine Animals Called Calves
The naming convention extends to a wide array of marine mammals, particularly those of great size. The young of all cetaceans, which include both the large baleen whales and the toothed whales like orcas, dolphins, and porpoises, are consistently known as calves. A newborn blue whale calf is impressively large, sometimes weighing over 2,000 kilograms, and must be able to swim immediately upon entering the water.
Marine calves rely on milk that is extremely rich in fat, which is necessary to fuel their rapid growth and to develop the blubber layer required for insulation in cold waters. The mother-calf bond in these aquatic species is often prolonged, with the calf swimming closely alongside its mother. Sirenians, the herbivorous marine mammals including manatees and dugongs, also refer to their young as calves.
Other Uses and Common Misnomers
While the term “calf” is primarily associated with large, precocial mammals, its usage can occasionally be found in less common contexts. For example, some species of sharks, though not mammals, have been anecdotally referred to as having calves, though this is not standard zoological terminology.
It is helpful to distinguish the term “calf” from other specialized names for young animals to avoid confusion. For instance, the young of horses, zebras, and donkeys are called foals, while the young of canids like wolves and foxes, or bears, are known as cubs or pups. Additionally, the young of seals and sea lions are generally referred to as pups, differentiating them from the calves of larger marine mammals.