A graminivore is a herbivorous animal that feeds primarily on grass, specifically "true" grasses, plants of the family

Poaceae Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and species cultivate ...

(also known as Graminae). Graminivory is a form of

grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to free range (roam around) and consume wild vegetations in order to feed conversion ratio, convert the otherwise indigestible (by human diges ...

. These herbivorous animals have digestive systems that are adapted to digest large amounts of

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

, which is abundant in fibrous plant matter and more difficult to break down for many other animals. As such, they have specialized

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s to aid in digestion and in some cases symbiotic bacteria that live in their digestive track and "assist" with the digestive process through fermentation as the matter travels through the intestines. Graminivores not only consume grasses, but also sedges. Grasses and sedges are both graminoids. Sedges are a part of the

Cyperaceae The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as wikt:sedge, sedges. The family (biology), family is large; botanists have species description, described some 5,500 known species in about 90 ...

family. Grasses are hollow with stems jointed and nodes, and typically have a round cross-section. Sedges are either round or triangular in cross section and not hollow.

Horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 mi ...

cattle Cattle (''Bos taurus'') are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus '' Bos''. Mature female cattle are calle ...

, geese, guinea pigs, hippopotamuses, capybara and giant pandas are examples of

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

graminivores. Some carnivorous vertebrates, such as dogs and cats, are known to eat grass occasionally. Grass consumption in dogs can be a way to rid their intestinal tract of parasites that may be threatening to the carnivore's health. Various

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s also have graminivorous diets. Many grasshoppers, such as individuals from the family Acrididae, have diets consisting primarily of plants from the family Poaceae. Although humans are not graminivores, we do get much of our nutrition from a type of grass called

cereal A cereal is a grass cultivated for its edible grain. Cereals are the world's largest crops, and are therefore staple foods. They include rice, wheat, rye, oats, barley, millet, and maize ( Corn). Edible grains from other plant families, ...

, and especially from the fruit of that grass which is called

grain A grain is a small, hard, dry fruit (caryopsis) – with or without an attached husk, hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and ...

. Graminivores generally exhibit a preference on which species of grass they choose to consume. For example, according to a study done on North American

bison A bison (: bison) is a large bovine in the genus ''Bison'' (from Greek, meaning 'wild ox') within the tribe Bovini. Two extant taxon, extant and numerous extinction, extinct species are recognised. Of the two surviving species, the American ...

feeding on shortgrass plains in north-eastern

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

, the cattle consumed a total of thirty-six different species of plant. Of that thirty-six, five grass species were favoured and consumed the most pervasively. The average consumption of these five species comprised about 80% of their diet. A few of these species include '' Aristida longiseta'', '' Muhlenbergia'' species, and '' Bouteloua gracilis''. Graminivores have morphological adaptations to feed on grass. The ''Theropithecus gelada'' (the gelada monkey, the only primate graminivore) has evolved with smaller incisors and larger molars for chewing, as well as strong thumbs and smaller second fingers to harvest graminoids. Some species are graminivores as larvae but not as adults, for example the Moroccan locust ( ''Dociostaurus maroccanus'').Benfekih, Leila, et al. "Do graminivores Caelifera consume the Poaceae according to their relative abundance?." File:Kangur.rudy.drs.jpg, Red kangaroo eating grass File:Horses.london.750pix.jpg,

s grazing in a field Image:Capybara Hattiesburg Zoo (70909b-42) 2560x1600.jpg, A capybara grazing at Hattiesburg Zoo

References

Ethology Herbivory {{ecology-stub