Mess with My Cows and You Will Meet The Crazy Heifer Shirt

Get a Britannica Premium subscription and gain access to exclusive contentSubscribe NowCows are well adapted for grazing (feeding on grass), with a wide mouth and specialized teeth for eating tough vegetation. Adults have 32 teeth but lack upper incisors and canines—they have a gummy pad instead that is used to help rip up grass. The molars have moon-shaped ridges that run parallel to the tongue, and thus chewing must be done with a circular motion to be effective.The most specialized adaptation that cows (and other ruminants) have is their massive four-chambered stomach, which acts as a fermentation vat. Inside the rumen, the largest chamber of the stomach, bacteria and other microorganisms digest tough plant fibres (cellulose). To aid in this process, cows regurgitate and re-chew food multiple times before it passes on to the rest of the digestive system via the other stomach chambers. This process, called “chewing the cud,” helps sort the digesta (the material being digested) and absorb nutrients. By taking time to re-chew their food later, cows avoid the need to chew well when they eat. This enables them to quickly ingest large quantities of grass while in the vulnerable head-down position required for grazing.

Mess with My Cows and You Will Meet The Crazy Heifer Shirt

The most specialized adaptation that cows (Bos taurus) and other ruminants have is their massive four-chambered stomach, which acts as a fermentation vat. Thechicken (Gallus gallus), however, has a three-chambered stomach, which includes an organ called the gizzard that is especially modified for grinding food.Encyclopædia Britannica, Inc.Domestication and economic productionCows are currently the most common domesticated ungulate (hoofed mammal), and they are found wherever humans live. Global stocks of cows were estimated at nearly one billion animals in 2016, with India, Brazil, and China having the largest populations (together maintaining approximately one-third of all cows).Skeleton of an aurochs (Bos primigenius), an extinct wild ox of Europe.AdstockRCows were first domesticated between 8,000 and 10,000 years ago from the aurochs (B. taurus primigenius), a wild species of cattle that once ranged across Eurasia. The wild aurochs became extinct in the early 1600s, the result of overhunting and loss of habitat due to the spread of agriculture (and domestic herds). Today, there are two broadly recognized forms of cow: the zebu or humped cattle from eastern Asia (B. taurus indicus) and cattle without humps (B. taurus taurus) from western Eurasia, although the two forms readily interbreed. Genetic studies suggest that both forms descend from the aurochs, but they are the products of independent domestication events.