While “cow” often brings to mind a single farm animal, the scientific classification of these animals, known as bovines, is more intricate. The question of how many “species of cows” exist delves into a diverse world, encompassing both domesticated animals and their wild relatives.
Defining “Cow” and “Species”
A species is generally defined as a group of organisms that can interbreed naturally and produce fertile offspring. This reproductive isolation is a key differentiator from a “breed,” which is a subgroup within a species that humans have developed through selective breeding for specific traits, such as different types of dogs. While “cow” colloquially refers to any domesticated bovine, particularly the female, in scientific terms, it primarily points to domesticated cattle within the genus Bos.
The Core Domesticated Cattle Species
The animals most commonly referred to as “cows” belong to two primary domesticated species: Bos taurus and Bos indicus.
Bos taurus, or European cattle, are typically humpless and originated from the Near East approximately 10,500 years ago. These cattle spread across Europe, Africa, and parts of Asia, adapting to temperate climates.
Bos indicus, known as Zebu or humped cattle, developed in the Indus Valley of South Asia around 8,000 to 9,000 years ago. They possess a characteristic fatty hump on their shoulders, loose skin, and are well-suited to hot, humid, and tropical environments due to their improved heat and parasite resistance.
Both Bos taurus and Bos indicus trace their ancestry to the extinct wild aurochs (Bos primigenius). While these two domesticated types are generally recognized as distinct species or subspecies, they can interbreed and produce fertile offspring, which sometimes leads to debate regarding their precise taxonomic status.
Wild Bovine Relatives and Their Connection to Domesticated Cattle
Beyond the familiar domesticated cattle, the genus Bos includes several other species.
The wild yak (Bos mutus) and its domesticated form (Bos grunniens) are robust bovines native to the Himalayan region of Central Asia. Gaurs (Bos gaurus), the largest wild cattle species, inhabit forested areas across South and Southeast Asia and are characterized by their massive, muscular build and impressive horns.
The gayal (Bos frontalis), also known as mithun, is a domesticated form of the gaur found in the Eastern Himalayas and parts of Southeast Asia, often recognized by its stocky body and thick horns. Bantengs (Bos javanicus) are another species within the Bos genus, native to Southeast Asia, with both wild and domesticated populations (Bali cattle). These bovines typically have a reddish-brown coat and white “stockings” on their legs.
Their existence highlights the considerable diversity within the direct lineage of what most people consider “cows.”
Beyond Domesticated Cattle: Other Bovine Animals Often Called “Cows”
Many other large, hoofed animals are colloquially referred to as “cows” or “buffalo” but belong to different genera within the larger Bovidae family. This family encompasses a wide range of ruminant mammals, including cattle, bison, buffalo, antelopes, sheep, and goats.
American bison (Bison bison) and European bison (Bison bonasus) are often called “buffalo” in North America but are distinct from true buffalo species. While traditionally placed in their own genus, Bison, genetic evidence suggests a close relationship with the Bos genus, sometimes leading to their classification as Bos bison.
Water buffalo (Bubalus bubalis) and African buffalo (Syncerus caffer) are also part of the Bovidae family but belong to separate genera, Bubalus and Syncerus, respectively. Water buffalo are widely domesticated for milk, meat, and draft power, particularly in Asia. African buffalo are wild, formidable animals found in various habitats across sub-Saharan Africa.
These animals, despite similarities, have followed unique evolutionary paths distinct from the Bos genus, underscoring the broad diversity within the Bovidae.