104-426: A deer ( pl. : deer) or true deer is a hoofed ruminant ungulate of the family Cervidae (informally the deer family ). Cervidae is divided into subfamilies Cervinae (which includes, among others, muntjac , elk (wapiti), red deer , and fallow deer ) and Capreolinae (which includes, among others reindeer (caribou), white-tailed deer , roe deer , and moose ). Male deer of almost all species (except
208-685: A clade sister to Cervidae . According to the study, Cervidae diverged from the Bovidae-Moschidae clade 27 to 28 million years ago. The following cladogram is based on a large-scale genome ruminant genome sequence study from 2019: Tragulidae [REDACTED] Antilocapridae [REDACTED] Giraffidae [REDACTED] Cervidae [REDACTED] Bovidae [REDACTED] Moschidae [REDACTED] Hofmann and Stewart divided ruminants into three major categories based on their feed type and feeding habits: concentrate selectors, intermediate types, and grass/roughage eaters, with
312-444: A clade sister to Cervidae. According to the study, Cervidae diverged from the Bovidae-Moschidae clade 27 to 28 million years ago. The following cladogram is based on the 2003 study. Tragulidae [REDACTED] Antilocapridae [REDACTED] Giraffidae [REDACTED] Cervidae [REDACTED] Bovidae [REDACTED] Ruminant Ruminants are herbivorous grazing or browsing artiodactyls belonging to
416-447: A global warming potential of 86 compared to CO 2 over a 20-year period. As a by-product of consuming cellulose, cattle belch out methane, there-by returning that carbon sequestered by plants back into the atmosphere. After about 10 to 12 years, that methane is broken down and converted back to CO 2 . Once converted to CO 2 , plants can again perform photosynthesis and fix that carbon back into cellulose. From here, cattle can eat
520-405: A broad central portion), white-tailed deer antlers include a series of tines sprouting upward from a forward-curving main beam, and those of the pudú are mere spikes. Antler development begins from the pedicel, a bony structure that appears on the top of the skull by the time the animal is a year old. The pedicel gives rise to a spiky antler the following year, that is replaced by a branched antler in
624-487: A cow. The role of saliva is to provide ample fluid for rumen fermentation and to act as a buffering agent. Rumen fermentation produces large amounts of organic acids, thus maintaining the appropriate pH of rumen fluids is a critical factor in rumen fermentation. After digesta passes through the rumen, the omasum absorbs excess fluid so that digestive enzymes and acid in the abomasum are not diluted. Tannins are phenolic compounds that are commonly found in plants. Found in
728-454: A disease which in the UK in 2005 cost £90 million in attempts to eradicate. In New Zealand, deer are thought to be important as vectors picking up M. bovis in areas where brushtail possums Trichosurus vulpecula are infected, and transferring it to previously uninfected possums when their carcasses are scavenged elsewhere. The white-tailed deer Odocoileus virginianus has been confirmed as
832-506: A four-chambered stomach. Some deer, such as those on the island of Rùm , do consume meat when it is available. Nearly all deer have a facial gland in front of each eye. The gland contains a strongly scented pheromone , used to mark its home range. Bucks of a wide range of species open these glands wide when angry or excited. All deer have a liver without a gallbladder . Deer also have a tapetum lucidum , which gives them sufficiently good night vision . All male deer have antlers , with
936-553: A nearly complete skeleton of Diacodexis discovered in 1982 gave rise to speculation that this ancestor could be closer to the non-ruminants than the ruminants. Andromeryx is another prominent prehistoric ruminant, but appears to be closer to the tragulids . The formation of the Himalayas and the Alps brought about significant geographic changes. This was the chief reason behind the extensive diversification of deer-like forms and
1040-542: A result of acclimatisation society releases in the 19th century, Australia has six introduced species of deer that have established sustainable wild populations. They are fallow deer, red deer, sambar, hog deer, rusa , and chital. Red deer were introduced into New Zealand in 1851 from English and Scottish stock. Many have been domesticated in deer farms since the late 1960s and are common farm animals there now. Seven other species of deer were introduced into New Zealand but none are as widespread as red deer. Deer constitute
1144-496: A role in mythology , religion, and literature throughout history, as well as in heraldry , such as red deer that appear in the coat of arms of Åland . Their economic importance includes the use of their meat as venison , their skins as soft, strong buckskin , and their antlers as handles for knives. Deer hunting has been a popular activity since the Middle Ages and remains a resource for many families today. The word deer
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#17327719363861248-415: A simple single-chambered stomach. Being hindgut fermenters , these animals ferment cellulose in an enlarged cecum . In smaller hindgut fermenters of the order Lagomorpha (rabbits, hares, and pikas), and Caviomorph rodents ( Guinea pigs , capybaras , etc.), material from the cecum is formed into cecotropes , passed through the large intestine, expelled and subsequently reingested to absorb nutrients in
1352-487: A smaller form, but a combination of anthropogenic and climatic pressures is now thought to be the most likely culprit. Meanwhile, the moose and reindeer radiated into North America from Siberia. Deer constitute the artiodactyl family Cervidae. This family was first described by German zoologist Georg August Goldfuss in Handbuch der Zoologie (1820). Three subfamilies were recognised: Capreolinae (first described by
1456-470: A three-compartment stomach instead of four like ruminants. The Hippopotamidae (comprising hippopotamuses ) are well-known examples. Pseudoruminants, like traditional ruminants, are foregut fermentors and most ruminate or chew cud . However, their anatomy and method of digestion differs significantly from that of a four-chambered ruminant. Monogastric herbivores , such as rhinoceroses , horses , guinea pigs , and rabbits , are not ruminants, as they have
1560-461: A warm, moist, anaerobic environment with a temperature range of 37.7 to 42.2 °C (99.9 to 108.0 °F) and a pH between 6.0 and 6.4. Without the help of microbes, ruminants would not be able to use nutrients from forages. The food is mixed with saliva and separates into layers of solid and liquid material. Solids clump together to form the cud or bolus . The cud is then regurgitated and chewed to completely mix it with saliva and to break down
1664-628: A wide range of climates (from tropic to arctic) and habitats (from open plains to forests). The population of domestic ruminants is greater than 3.5 billion, with cattle, sheep, and goats accounting for about 95% of the total population. Goats were domesticated in the Near East circa 8000 BC. Most other species were domesticated by 2500 BC., either in the Near East or southern Asia. Ruminating animals have various physiological features that enable them to survive in nature. One feature of ruminants
1768-781: A wide variety of vegetation. The teeth of deer are adapted to feeding on vegetation, and like other ruminants, they lack upper incisors , instead having a tough pad at the front of their upper jaw. Deer are browsers , and feed primarily on foliage of grasses , sedges , forbs , shrubs and trees , secondarily on lichens in northern latitudes during winter. They have small, unspecialized stomachs by ruminant standards, and high nutrition requirements. Rather than eating and digesting vast quantities of low-grade fibrous food as, for example, sheep and cattle do, deer select easily digestible shoots, young leaves, fresh grasses, soft twigs, fruit, fungi , and lichens . The low-fibered food, after minimal fermentation and shredding, passes rapidly through
1872-641: Is a havier . A group of any species is a herd . The adjective of relation is cervine ; like the family name Cervidae , this is from Latin : cervus , meaning ' stag ' or ' deer ' . Deer live in a variety of biomes , ranging from tundra to the tropical rainforest . While often associated with forests, many deer are ecotone species that live in transitional areas between forests and thickets (for cover) and prairie and savanna (open space). The majority of large deer species inhabit temperate mixed deciduous forest, mountain mixed coniferous forest, tropical seasonal/dry forest, and savanna habitats around
1976-570: Is a stem-based definition for Ruminantiamorpha, and is more inclusive than the crown group Ruminantia. As a crown group, Ruminantia only includes the last common ancestor of all extant (living) ruminants and their descendants (living or extinct ), whereas Ruminantiamorpha, as a stem group, also includes more basal extinct ruminant ancestors that are more closely related to living ruminants than to other members of Artiodactyla. When considering only living taxa ( neontology ), this makes Ruminantiamorpha and Ruminantia synonymous , and only Ruminantia
2080-531: Is estimated to contain 10–50 billion bacteria and 1 million protozoa, as well as several yeasts and fungi. Since the environment inside a rumen is anaerobic , most of these microbial species are obligate or facultative anaerobes that can decompose complex plant material, such as cellulose , hemicellulose , starch , and proteins . The hydrolysis of cellulose results in sugars, which are further fermented to acetate, lactate, propionate, butyrate, carbon dioxide, and methane . As bacteria conduct fermentation in
2184-445: Is only slightly taller and heavier. Sexual dimorphism is quite pronounced – in most species males tend to be larger than females, and, except for the reindeer, only males have antlers. Coat colour generally varies between red and brown, though it can be as dark as chocolate brown in the tufted deer or have a grayish tinge as in elk. Different species of brocket deer vary from gray to reddish brown in coat colour. Several species such as
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#17327719363862288-412: Is strong enough to walk with its mother. The fawn and its mother stay together for about one year. A male usually leaves and never sees his mother again, but females sometimes come back with their own fawns and form small herds. In some areas of the UK, deer (especially fallow deer due to their gregarious behaviour ) have been implicated as a possible reservoir for transmission of bovine tuberculosis ,
2392-498: Is the moose , which is nearly 2.6 metres (8 ft 6 in) tall and weighs up to 800 kilograms (1,800 lb). The elk stands 1.4–2 metres (4 ft 7 in – 6 ft 7 in) at the shoulder and weighs 240–450 kilograms (530–990 lb). The northern pudu is the smallest deer in the world; it reaches merely 32–35 centimetres ( 12 + 1 ⁄ 2 –14 in) at the shoulder and weighs 3.3–6 kilograms ( 7 + 1 ⁄ 4 – 13 + 1 ⁄ 4 lb). The southern pudu
2496-408: Is the large ruminal storage capacity that gives them the ability to consume feed rapidly and complete the chewing process later. This is known as rumination, which consists of the regurgitation of feed, rechewing, resalivation, and reswallowing. Rumination reduces particle size, which enhances microbial function and allows the digesta to pass more easily through the digestive tract. Vertebrates lack
2600-439: Is their continuously growing teeth. During grazing, the silica content in forage causes abrasion of the teeth. This is compensated for by continuous tooth growth throughout the ruminant's life, as opposed to humans or other nonruminants, whose teeth stop growing after a particular age. Most ruminants do not have upper incisors; instead, they have a thick dental pad to thoroughly chew plant-based food. Another feature of ruminants
2704-938: Is used. Thus, Ruminantiamorpha is only used in the context of paleontology . Accordingly, Spaulding grouped some genera of the extinct family Anthracotheriidae within Ruminantiamorpha (but not in Ruminantia), but placed others within Ruminantiamorpha's sister clade, Cetancodontamorpha . Ruminantia's placement within Artiodactyla can be represented in the following cladogram : Tylopoda (camels) [REDACTED] Suina (pigs) [REDACTED] Tragulidae (mouse deer) [REDACTED] Pecora (horn bearers) [REDACTED] Hippopotamidae (hippopotamuses) [REDACTED] Cetacea (whales) [REDACTED] Within Ruminantia,
2808-456: Is very important because it provides liquid for the microbial population, recirculates nitrogen and minerals, and acts as a buffer for the rumen pH. The type of feed the animal consumes affects the amount of saliva that is produced. Though the rumen and reticulum have different names, they have very similar tissue layers and textures, making it difficult to visually separate them. They also perform similar tasks. Together, these chambers are called
2912-647: The Barbary stag , a subspecies of red deer that is confined to the Atlas Mountains in the northwest of the continent. Another extinct species of deer, Megaceroides algericus , was present in North Africa until 6000 years ago. Fallow deer have been introduced to South Africa . Small species of brocket deer and pudús of Central and South America , and muntjacs of Asia generally occupy dense forests and are less often seen in open spaces, with
3016-495: The Caucasus Mountains have forest areas that are not only home to sizable deer populations but also other animals that were once abundant such as the wisent, Eurasian lynx , Iberian lynx , wolves , and brown bears . The highest concentration of large deer species in temperate Asia occurs in the mixed deciduous forests, mountain coniferous forests, and taiga bordering North Korea, Manchuria (Northeastern China), and
3120-633: The Pleistocene have been excavated in China and the Himalayas. While Cervus and Dama appeared nearly 3 Mya, Axis emerged during the late Pliocene–Pleistocene. The tribes Capreolini and Rangiferini appeared around 4–7 Mya. Around 5 Mya, the rangiferina † Bretzia and † Eocoileus were the first cervids to reach North America. This implies the Bering Strait could be crossed during
3224-957: The Sami people of Finland and Scandinavia, the Tungusic peoples, Mongolians, and Turkic peoples of Southern Siberia, Northern Mongolia, and the Ussuri Region have also taken to raising semi-domesticated herds of Asian caribou. The highest concentration of large deer species in the tropics occurs in Southern Asia in India's Indo-Gangetic Plain Region and Nepal 's Terai Region. These fertile plains consist of tropical seasonal moist deciduous, dry deciduous forests, and both dry and wet savannas that are home to chital , hog deer , barasingha , Indian sambar , and Indian muntjac . Grazing species such as
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3328-530: The Tethys Ocean disappeared to give way to vast stretches of grassland; these provided the deer with abundant protein-rich vegetation that led to the development of ornamental antlers and allowed populations to flourish and colonise areas. As antlers had become pronounced, the canines were either lost or became poorly represented (as in elk), probably because diet was no longer browse -dominated and antlers were better display organs. In muntjac and tufted deer,
3432-556: The Tragulidae (mouse deer) are considered the most basal family, with the remaining ruminants classified as belonging to the infraorder Pecora . Until the beginning of the 21st century it was understood that the family Moschidae (musk deer) was sister to Cervidae . However, a 2003 phylogenetic study by Alexandre Hassanin (of National Museum of Natural History, France ) and colleagues, based on mitochondrial and nuclear analyses, revealed that Moschidae and Bovidae form
3536-524: The forest canopy without penetrating it to any great extent, but above the forest floor . Only a small percentage of light penetrates the canopy so understory vegetation is generally shade-tolerant . The understory typically consists of trees stunted through lack of light, other small trees with low light requirements, saplings, shrubs, vines and undergrowth. Small trees such as holly and dogwood are understory specialists. In temperate deciduous forests , many understory plants start into growth earlier in
3640-489: The merycodontines eventually gave rise to the modern pronghorn. The Cervinae emerged as the first group of extant cervids around 7–9 Mya, during the late Miocene in central Asia. The tribe Muntiacini made its appearance as † Muntiacus leilaoensis around 7–8 Mya; The early muntjacs varied in size–as small as hares or as large as fallow deer. They had tusks for fighting and antlers for defence. Capreolinae followed soon after; Alceini appeared 6.4–8.4 Mya. Around this period,
3744-430: The suborder Ruminantia that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microbial actions. The process, which takes place in the front part of the digestive system and therefore is called foregut fermentation , typically requires the fermented ingesta (known as cud ) to be regurgitated and chewed again. The process of rechewing
3848-499: The water deer ), as well as female reindeer, grow and shed new antlers each year. These antlers are bony extensions of the skull and are often used for combat between males. The musk deer ( Moschidae ) of Asia and chevrotains ( Tragulidae ) of tropical African and Asian forests are separate families that are also in the ruminant clade Ruminantia ; they are not especially closely related to Cervidae. Deer appear in art from Paleolithic cave paintings onwards, and they have played
3952-410: The (one's) cud' is to reflect or meditate. In psychology, "rumination" refers to a pattern of thinking, and is unrelated to digestive physiology. Methane is produced by a type of archaea , called methanogens , as described above within the rumen, and this methane is released to the atmosphere. The rumen is the major site of methane production in ruminants. Methane is a strong greenhouse gas with
4056-549: The British Columbia side, and Banff National Park , Jasper National Park , and Glacier National Park (U.S.) on the Alberta and Montana sides. Mountain slope habitats vary from moist coniferous/mixed forested habitats to dry subalpine/pine forests with alpine meadows higher up. The foothills and river valleys between the mountain ranges provide a mosaic of cropland and deciduous parklands. The rare woodland caribou have
4160-508: The Cervidae, are believed to have evolved from Diacodexis , the earliest known artiodactyl (even-toed ungulate), 50–55 Mya in the Eocene. Diacodexis , nearly the size of a rabbit , featured the talus bone characteristic of all modern even-toed ungulates . This ancestor and its relatives occurred throughout North America and Eurasia, but were on the decline by at least 46 Mya. Analysis of
4264-462: The English zoologist Joshua Brookes in 1828), Cervinae (described by Goldfuss) and Hydropotinae (first described by French zoologist Édouard Louis Trouessart in 1898). Other attempts at the classification of deer have been based on morphological and genetic differences. The Anglo-Irish naturalist Victor Brooke suggested in 1878 that deer could be bifurcated into two classes on the according to
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4368-770: The European Dremotherium ; these sabre-toothed animals are believed to have been the direct ancestors of all modern antlered deer, though they themselves lacked antlers. Another contemporaneous form was the four-horned protoceratid Protoceras , that was replaced by Syndyoceras in the Miocene; these animals were unique in having a horn on the nose. Late Eocene fossils dated approximately 35 million years ago, which were found in North America, show that Syndyoceras had bony skull outgrowths that resembled non-deciduous antlers. Fossil evidence suggests that
4472-747: The Ice Ages, but afterwards became restricted primarily to the Anatolian Peninsula, in present-day Turkey. Present-day fallow deer populations in Europe are a result of historic man-made introductions of this species, first to the Mediterranean regions of Europe, then eventually to the rest of Europe. They were initially park animals that later escaped and reestablished themselves in the wild. Historically, Europe's deer species shared their deciduous forest habitat with other herbivores, such as
4576-636: The Indian Subcontinent) boasts the most species of deer in the world, with most species being found in Asia. Europe, in comparison, has lower diversity in plant and animal species. Many national parks and protected reserves in Europe have populations of red deer, roe deer , and fallow deer. These species have long been associated with the continent of Europe, but also inhabit Asia Minor , the Caucasus Mountains , and Northwestern Iran . "European" fallow deer historically lived over much of Europe during
4680-401: The U.S., and 22% of the total U.S. methane emissions . The meat from domestically raised ruminants has a higher carbon equivalent footprint than other meats or vegetarian sources of protein based on a global meta-analysis of lifecycle assessment studies. Methane production by meat animals, principally ruminants, is estimated 15–20% global production of methane, unless the animals were hunted in
4784-547: The Ussuri Region (Russia). These are among some of the richest deciduous and coniferous forests in the world where one can find Siberian roe deer , sika deer , elk, and moose. Asian caribou occupy the northern fringes of this region along the Sino-Russian border. Deer such as the sika deer, Thorold's deer , Central Asian red deer , and elk have historically been farmed for their antlers by Han Chinese , Turkic peoples , Tungusic peoples , Mongolians , and Koreans . Like
4888-442: The ability to hydrolyse the beta [1–4] glycosidic bond of plant cellulose due to the lack of the enzyme cellulase . Thus, ruminants completely depend on the microbial flora, present in the rumen or hindgut, to digest cellulose. Digestion of food in the rumen is primarily carried out by the rumen microflora, which contains dense populations of several species of bacteria , protozoa , sometimes yeasts and other fungi – 1 ml of rumen
4992-419: The abomasum. This is the gastric compartment of the ruminant stomach. The abomasum is the direct equivalent of the monogastric stomach, and digesta is digested here in much the same way. This compartment releases acids and enzymes that further digest the material passing through. This is also where the ruminant digests the microbes produced in the rumen. Digesta is finally moved into the small intestine , where
5096-516: The absorption of nutrients by reducing the populations of proteolytic rumen bacteria. Very high levels of tannin intake can produce toxicity that can even cause death. Animals that normally consume tannin-rich plants can develop defensive mechanisms against tannins, such as the strategic deployment of lipids and extracellular polysaccharides that have a high affinity to binding to tannins. Some ruminants (goats, deer, elk, moose) are able to consume food high in tannins (leaves, twigs, bark) due to
5200-405: The alimentary canal. The deer require a large amount of minerals such as calcium and phosphate in order to support antler growth, and this further necessitates a nutrient-rich diet. There are some reports of deer engaging in carnivorous activity, such as eating dead alewives along lakeshores or depredating the nests of northern bobwhites . Nearly all cervids are so-called uniparental species:
5304-614: The antlers as well as the canines are small. The tragulids have long canines to this day. With the onset of the Pliocene , the global climate became cooler. A fall in the sea-level led to massive glaciation; consequently, grasslands abounded in nutritious forage. Thus a new spurt in deer populations ensued. The oldest member of Cervini, † Cervocerus novorossiae , appeared around the transition from Miocene to Pliocene (4.2–6 Mya) in Eurasia; cervine fossils from early Pliocene to as late as
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#17327719363865408-869: The antlers create grooves that allow another male's antlers to lock into place. This allows the males to wrestle without risking injury to the face. Antlers are correlated to an individual's position in the social hierarchy and its behaviour. For instance, the heavier the antlers, the higher the individual's status in the social hierarchy, and the greater the delay in shedding the antlers; males with larger antlers tend to be more aggressive and dominant over others. Antlers can be an honest signal of genetic quality; males with larger antlers relative to body size tend to have increased resistance to pathogens and higher reproductive capacity. In elk in Yellowstone National Park , antlers also provide protection against predation by wolves . Homology of tines, that is,
5512-463: The assumption that feeding habits in ruminants cause morphological differences in their digestive systems, including salivary glands, rumen size, and rumen papillae. However, Woodall found that there is little correlation between the fiber content of a ruminant's diet and morphological characteristics, meaning that the categorical divisions of ruminants by Hofmann and Stewart warrant further research. Also, some mammals are pseudoruminants , which have
5616-500: The basis of diploid number of chromosomes in the late 20th century has been flawed by several inconsistencies. In 1987, the zoologists Colin Groves and Peter Grubb identified three subfamilies: Cervinae, Hydropotinae and Odocoileinae; they noted that the hydropotines lack antlers, and the other two subfamilies differ in their skeletal morphology. They reverted from this classification in 2000. Molecular phylogenetic analyses since
5720-687: The branching structure of antlers among species, have been discussed before the 1900s. Recently, a new method to describe the branching structure of antlers and determining homology of tines was developed. Most deer bear 32 teeth; the corresponding dental formula is: 0.0.3.3 3.1.3.3 . The elk and the reindeer may be exceptions, as they may retain their upper canines and thus have 34 teeth (dental formula: 0.1.3.3 3.1.3.3 ). The Chinese water deer, tufted deer, and muntjac have enlarged upper canine teeth forming sharp tusks, while other species often lack upper canines altogether. The cheek teeth of deer have crescent ridges of enamel, which enable them to grind
5824-405: The canopy, and the shaded ground does not vary in temperature as much as open ground. This causes a proliferation of ferns , mosses , and fungi and encourages nutrient recycling , which provides favorable habitats for many animals and plants. The understory is the underlying layer of vegetation in a forest or wooded area, especially the trees and shrubs growing between the forest canopy and
5928-447: The cecotropes. The primary difference between ruminants and nonruminants is that ruminants' stomachs have four compartments: The first two chambers are the rumen and the reticulum. These two compartments make up the fermentation vat and are the major site of microbial activity. Fermentation is crucial to digestion because it breaks down complex carbohydrates, such as cellulose, and enables the animal to use them. Microbes function best in
6032-512: The chital, the fallow deer and the sika deer feature white spots on a brown coat. Coat of reindeer shows notable geographical variation. Deer undergo two moults in a year; for instance, in red deer the red, thin-haired summer coat is gradually replaced by the dense, greyish brown winter coat in autumn, which in turn gives way to the summer coat in the following spring. Moulting is affected by the photoperiod . Deer are also excellent jumpers and swimmers. Deer are ruminants , or cud-chewers, and have
6136-538: The course of the year. As a rule forest understories also experience higher humidity than exposed areas. The forest canopy reduces solar radiation, so the ground does not heat up or cool down as rapidly as open ground. Consequently, the understory dries out more slowly than more exposed areas do. The greater humidity encourages epiphytes such as ferns and mosses, and allows fungi and other decomposers to flourish. This drives nutrient cycling , and provides favorable microclimates for many animals and plants , such as
6240-579: The cud to further break down plant matter and stimulate digestion is called rumination . The word "ruminant" comes from the Latin ruminare , which means "to chew over again". The roughly 200 species of ruminants include both domestic and wild species. Ruminating mammals include cattle , all domesticated and wild bovines , goats , sheep , giraffes , deer , gazelles , and antelopes . It has also been suggested that notoungulates also relied on rumination, as opposed to other atlantogenatans that rely on
6344-400: The digestion and absorption of nutrients occurs. The small intestine is the main site of nutrient absorption. The surface area of the digesta is greatly increased here because of the villi that are in the small intestine. This increased surface area allows for greater nutrient absorption. Microbes produced in the reticulorumen are also digested in the small intestine. After the small intestine is
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#17327719363866448-413: The earliest members of the superfamily Cervoidea appeared in Eurasia in the Miocene. Dicrocerus , Euprox and Heteroprox were probably the first antlered cervids. Dicrocerus featured single-forked antlers that were shed regularly. Stephanocemas had more developed and diffuse ("crowned") antlers. Procervulus ( Palaeomerycidae ) also had antlers that were not shed. Contemporary forms such as
6552-646: The early Eocene , and gradually developed into the first antlered cervoids (the superfamily of cervids and related extinct families) in the Miocene . Eventually, with the development of antlers, the tusks as well as the upper incisors disappeared. Thus, evolution of deer took nearly 30 million years. Biologist Valerius Geist suggests evolution to have occurred in stages. There are not many prominent fossils to trace this evolution, but only fragments of skeletons and antlers that might be easily confused with false antlers of non-cervid species. The ruminants , ancestors of
6656-484: The early Miocene . Ruminantia is a crown group of ruminants within the order Artiodactyla , cladistically defined by Spaulding et al. as "the least inclusive clade that includes Bos taurus (cow) and Tragulus napu (mouse deer)". Ruminantiamorpha is a higher-level clade of artiodactyls, cladistically defined by Spaulding et al. as "Ruminantia plus all extinct taxa more closely related to extant members of Ruminantia than to any other living species." This
6760-687: The early Pleistocene, probably as a result of abundant resources to drive evolution. The early Pleistocene cervid † Eucladoceros was comparable in size to the modern elk. † Megaloceros (Pliocene–Pleistocene) featured the Irish elk ( M. giganteus ), one of the largest known cervids . The Irish elk reached 2 metres ( 6 + 1 ⁄ 2 ft) at the shoulder and had heavy antlers that spanned 3.6 metres (11 ft 10 in) from tip to tip. These large animals were traditionally thought to have faced extinction due to conflict between sexual selection for large antlers and body and natural selection for
6864-664: The ecological niches of the ibex and wild goat , with the fawns behaving more like goat kids. The highest concentration of large deer species in temperate North America lies in the Canadian Rocky Mountain and Columbia Mountain regions between Alberta and British Columbia where all five North American deer species ( white-tailed deer , mule deer , caribou , elk , and moose ) can be found. This region has several clusters of national parks including Mount Revelstoke National Park , Glacier National Park (Canada) , Yoho National Park , and Kootenay National Park on
6968-765: The emergence of cervids from the Oligocene to the early Pliocene . The latter half of the Oligocene (28–34 Mya) saw the appearance of the European Eumeryx and the North American Leptomeryx . The latter resembled modern-day bovids and cervids in dental morphology (for instance, it had brachyodont molars), while the former was more advanced . Other deer-like forms included the North American Blastomeryx and
7072-425: The end of the leafless season, understory plants take advantage of the shelter of the still leafless canopy plants to "leaf out" before the canopy trees do. This is important because it provides the understory plants with a window in which to photosynthesize without the canopy shading them. This brief period (usually 1–2 weeks) is often a crucial period in which the plant can maintain a net positive carbon balance over
7176-408: The end of their first winter. In the first twenty minutes of a fawn's life, the fawn begins to take its first steps. Its mother licks it clean until it is almost free of scent, so predators will not find it. Its mother leaves often to graze, and the fawn does not like to be left behind. Sometimes its mother must gently push it down with her foot. The fawn stays hidden in the grass for one week until it
7280-750: The endangered barasingha and very common chital are gregarious and live in large herds. Indian sambar can be gregarious but are usually solitary or live in smaller herds. Hog deer are solitary and have lower densities than Indian muntjac. Deer can be seen in several national parks in India, Nepal, and Sri Lanka of which Kanha National Park , Dudhwa National Park , and Chitwan National Park are most famous. Sri Lanka's Wilpattu National Park and Yala National Park have large herds of Indian sambar and chital. The Indian sambar are more gregarious in Sri Lanka than other parts of their range and tend to form larger herds than elsewhere. The Chao Praya River Valley of Thailand
7384-558: The exception of the water deer , in which males have long tusk-like canines that reach below the lower jaw. Females generally lack antlers, though female reindeer bear antlers smaller and less branched than those of the males. Occasionally females in other species may develop antlers, especially in telemetacarpal deer such as European roe deer, red deer, white-tailed deer and mule deer and less often in plesiometacarpal deer. A study of antlered female white-tailed deer noted that antlers tend to be small and malformed, and are shed frequently around
7488-1000: The extinct tarpan (forest horse), extinct aurochs (forest ox), and the endangered wisent (European bison). Good places to see deer in Europe include the Scottish Highlands , the Austrian Alps , the wetlands between Austria , Hungary , and the Czech Republic , and some National Parks, including Doñana National Park in Spain , the Veluwe in the Netherlands , the Ardennes in Belgium , and Białowieża National Park in Poland . Spain , Eastern Europe , and
7592-416: The features of the second and fifth metacarpal bones of their forelimbs: Plesiometacarpalia (most Old World deer) and Telemetacarpalia (most New World deer). He treated the musk deer as a cervid, placing it under Telemetacarpalia. While the telemetacarpal deer showed only those elements located far from the joint, the plesiometacarpal deer retained the elements closer to the joint as well. Differentiation on
7696-531: The foothills and river valley bottoms of the Canadian Rockies owing to conversion of land to cropland and the clearing of coniferous forests allowing more deciduous vegetation to grow up the mountain slopes. They also live in the aspen parklands north of Calgary and Edmonton, where they share habitat with the moose. The adjacent Great Plains grassland habitats are left to herds of elk, American bison , and pronghorn . The Eurasian Continent (including
7800-399: The forest floor. Plants in the understory comprise an assortment of seedlings and saplings of canopy trees together with specialist understory shrubs and herbs. Young canopy trees often persist in the understory for decades as suppressed juveniles until an opening in the forest overstory permits their growth into the canopy. In contrast understory shrubs complete their life cycles in
7904-418: The large intestine. The major roles here are breaking down mainly fiber by fermentation with microbes, absorption of water (ions and minerals) and other fermented products, and also expelling waste. Fermentation continues in the large intestine in the same way as in the reticulorumen. Only small amounts of glucose are absorbed from dietary carbohydrates. Most dietary carbohydrates are fermented into VFAs in
8008-508: The late Miocene–Pliocene; this appears highly probable as the camelids migrated into Asia from North America around the same time. Deer invaded South America in the late Pliocene (2.5–3 Mya) as part of the Great American Interchange , thanks to the recently formed Isthmus of Panama , and emerged successful due to the small number of competing ruminants in the continent. Large deer with impressive antlers evolved during
8112-445: The latter half of the 2000s all show that hydropotes is a sister taxon of Capreolus , and “Hydropotinae” became outdated subfamily. Until 2003, it was understood that the family Moschidae (musk deer) was sister to Cervidae. Then a phylogenetic study by Alexandre Hassanin (of National Museum of Natural History, France ) and colleagues, based on mitochondrial and nuclear analyses, revealed that Moschidae and Bovidae form
8216-623: The leaf, bud, seed, root, and stem tissues, tannins are widely distributed in many different species of plants. Tannins are separated into two classes: hydrolysable tannins and condensed tannins . Depending on their concentration and nature, either class can have adverse or beneficial effects. Tannins can be beneficial, having been shown to increase milk production, wool growth, ovulation rate, and lambing percentage, as well as reducing bloat risk and reducing internal parasite burdens. Tannins can be toxic to ruminants, in that they precipitate proteins, making them unavailable for digestion, and they inhibit
8320-476: The modern English sense by the end of the Middle English period, around 1500. All modern Germanic languages save English and Scots retain the more general sense: for example, Dutch / Frisian dier , German Tier , and Norwegian dyr mean ' animal ' . For many types of deer in modern English usage, the male is a buck and the female a doe , but the terms vary with dialect, and according to
8424-516: The more typical hindgut fermentation , though this is not entirely certain. Ruminants represent the most diverse group of living ungulates . The suborder Ruminantia includes six different families: Tragulidae , Giraffidae , Antilocapridae , Cervidae , Moschidae , and Bovidae . The first fossil ruminants appeared in the Early Eocene and were small, likely omnivorous, forest-dwellers. Artiodactyls with cranial appendages first occur in
8528-413: The most restricted range living at higher altitudes in the subalpine meadows and alpine tundra areas of some of the mountain ranges. Elk and mule deer both migrate between the alpine meadows and lower coniferous forests and tend to be most common in this region. Elk also inhabit river valley bottomlands, which they share with White-tailed deer. The White-tailed deer have recently expanded their range within
8632-460: The particle size. Smaller particle size allows for increased nutrient absorption. Fiber, especially cellulose and hemicellulose , is primarily broken down in these chambers by microbes (mostly bacteria , as well as some protozoa , fungi , and yeast ) into the three volatile fatty acids (VFAs): acetic acid , propionic acid , and butyric acid . Protein and nonstructural carbohydrate ( pectin , sugars , and starches ) are also fermented. Saliva
8736-430: The plants and the cycle begins once again. In essence, the methane belched from cattle is not adding new carbon to the atmosphere. Rather it is part of the natural cycling of carbon through the biogenic carbon cycle . In 2010, enteric fermentation accounted for 43% of the total greenhouse gas emissions from all agricultural activity in the world, 26% of the total greenhouse gas emissions from agricultural activity in
8840-649: The possible exception of the Indian muntjac . There are also several species of deer that are highly specialized and live almost exclusively in mountains, grasslands, swamps, and "wet" savannas, or riparian corridors surrounded by deserts . Some deer have a circumpolar distribution in both North America and Eurasia . Examples include the caribou that live in Arctic tundra and taiga (boreal forests) and moose that inhabit taiga and adjacent areas. Huemul deer ( taruca and Chilean huemul ) of South America 's Andes fill
8944-568: The presence in their saliva of tannin-binding proteins. The Law of Moses in the Bible allowed the eating of some mammals that had cloven hooves (i.e. members of the order Artiodactyla ) and "that chew the cud", a stipulation preserved to this day in Jewish dietary laws . The verb 'to ruminate' has been extended metaphorically to mean to ponder thoughtfully or to meditate on some topic. Similarly, ideas may be 'chewed on' or 'digested'. 'Chew
9048-408: The reticulorumen. The degraded digesta, which is now in the lower liquid part of the reticulorumen, then passes into the next chamber, the omasum. This chamber controls what is able to pass into the abomasum. It keeps the particle size as small as possible in order to pass into the abomasum. The omasum also absorbs volatile fatty acids and ammonia. After this, the digesta is moved to the true stomach,
9152-401: The right spot and never really find it." Deer appear to be immune to this parasite; it passes through the digestive system and is excreted in the feces. The parasite is not screened by the moose intestine, and passes into the brain where damage is done that is externally apparent, both in behaviour and in gait. Deer, elk and moose in North America may suffer from chronic wasting disease , which
9256-541: The rumen, they consume about 10% of the carbon, 60% of the phosphorus, and 80% of the nitrogen that the ruminant ingests. To reclaim these nutrients, the ruminant then digests the bacteria in the abomasum . The enzyme lysozyme has adapted to facilitate digestion of bacteria in the ruminant abomasum. Pancreatic ribonuclease also degrades bacterial RNA in the ruminant small intestine as a source of nitrogen. During grazing, ruminants produce large amounts of saliva – estimates range from 100 to 150 litres of saliva per day for
9360-599: The rumen. The glucose needed as energy for the brain and for lactose and milk fat in milk production, as well as other uses, comes from nonsugar sources, such as the VFA propionate, glycerol, lactate, and protein. The VFA propionate is used for around 70% of the glucose and glycogen produced and protein for another 20% (50% under starvation conditions). Wild ruminants number at least 75 million and are native to all continents except Antarctica and Australia. Nearly 90% of all species are found in Eurasia and Africa. Species inhabit
9464-414: The second most diverse family of artiodactyla after bovids. Though of a similar build, deer are strongly distinguished from antelopes by their antlers , which are temporary and regularly regrown unlike the permanent horns of bovids. Characteristics typical of deer include long, powerful legs, a diminutive tail and long ears. Deer exhibit a broad variation in physical proportions. The largest extant deer
9568-724: The shade of the forest canopy. Some smaller tree species, such as dogwood and holly , rarely grow tall and generally are understory trees. The canopy of a tropical forest is typically about 10 m (33 ft) thick, and intercepts around 95% of the sunlight. The understory therefore receives less intense light than plants in the canopy and such light as does penetrate is impoverished in wavelengths of light that are most effective for photosynthesis. Understory plants therefore must be shade tolerant —they must be able to photosynthesize adequately using such light as does reach their leaves. They often are able to use wavelengths that canopy plants cannot. In temperate deciduous forests towards
9672-424: The size of the species. The male red deer is a stag , while for other large species the male is a bull , the female a cow , as in cattle. In older usage, the male of any species is a hart , especially if over five years old, and the female is a hind , especially if three or more years old. The young of small species is a fawn and of large species a calf ; a very small young may be a kid . A castrated male
9776-522: The sole maintenance host in the Michigan outbreak of bovine tuberculosis which remains a significant barrier to the US nationwide eradication of the disease in livestock. Moose and deer can carry rabies . Docile moose may suffer from brain worm , a helminth which drills holes through the brain in its search for a suitable place to lay its eggs. A government biologist states that "They move around looking for
9880-571: The third year. This process of losing a set of antlers to develop a larger and more branched set continues for the rest of the life. The antlers emerge as soft tissues (known as velvet antlers ) and progressively harden into bony structures (known as hard antlers), following mineralisation and blockage of blood vessels in the tissue, from the tip to the base. Antlers might be one of the most exaggerated male secondary sexual characteristics , and are intended primarily for reproductive success through sexual selection and for combat. The tines (forks) on
9984-537: The time of parturition. The fallow deer and the various subspecies of the reindeer have the largest as well as the heaviest antlers, both in absolute terms as well as in proportion to body mass (an average of eight grams per kilogram of body mass); the tufted deer, on the other hand, has the smallest antlers of all deer, while the pudú has the lightest antlers with respect to body mass (0.6 g per kilogram of body mass). The structure of antlers show considerable variation; while fallow deer and elk antlers are palmate (with
10088-456: The various Asian rhinoceros species, various antelope species (such as nilgai , four-horned antelope , blackbuck , and Indian gazelle in India), and wild oxen (such as wild Asian water buffalo , gaur , banteng , and kouprey ). One way that different herbivores can survive together in a given area is for each species to have different food preferences, although there may be some overlap. As
10192-571: The wild. The current U.S. domestic beef and dairy cattle population is around 90 million head, approximately 50% higher than the peak wild population of American bison of 60 million head in the 1700s, which primarily roamed the part of North America that now makes up the United States. Understory In forestry and ecology , understory ( American English ), or understorey ( Commonwealth English ), also known as underbrush or undergrowth , includes plant life growing beneath
10296-512: The world. Clearing open areas within forests to some extent may actually benefit deer populations by exposing the understory and allowing the types of grasses, weeds, and herbs to grow that deer like to eat. Access to adjacent croplands may also benefit deer. Adequate forest or brush cover must still be provided for populations to grow and thrive. Deer are widely distributed, with indigenous representatives in all continents except Antarctica and Australia , though Africa has only one native deer,
10400-472: The year than the canopy trees, to make use of the greater availability of light at that particular time of year. A gap in the canopy caused by the death of a tree stimulates the potential emergent trees into competitive growth as they grow upwards to fill the gap. These trees tend to have straight trunks and few lower branches. At the same time, the bushes, undergrowth, and plant life on the forest floor become denser. The understory experiences greater humidity than
10504-547: The young, known in most species as fawns, are only cared for by the mother, most often called a doe. A doe generally has one or two fawns at a time (triplets, while not unknown, are uncommon). Mating season typically begins in later August and lasts until December. Some species mate until early March. The gestation period is anywhere up to ten months for the European roe deer. Most fawns are born with their fur covered with white spots, though in many species they lose these spots by
10608-512: Was identified at a Colorado laboratory in the 1960s and is believed to be a prion disease. Out of an abundance of caution hunters are advised to avoid contact with specified risk material (SRM) such as the brain, spinal column or lymph nodes. Deboning the meat when butchering and sanitizing the knives and other tools used to butcher are amongst other government recommendations. Deer are believed to have evolved from antlerless, tusked ancestors that resembled modern duikers and diminutive deer in
10712-474: Was once primarily tropical seasonal moist deciduous forest and wet savanna that hosted populations of hog deer, the now-extinct Schomburgk's deer , Eld's deer , Indian sambar, and Indian muntjac. Both the hog deer and Eld's deer are rare, whereas Indian sambar and Indian muntjac thrive in protected national parks, such as Khao Yai . Many of these South Asian and Southeast Asian deer species also share their habitat with other herbivores , such as Asian elephants ,
10816-422: Was originally broad in meaning, becoming more specific with time. Old English dēor and Middle English der meant a wild animal of any kind. Cognates of Old English dēor in other dead Germanic languages have the general sense of animal , such as Old High German tior , Old Norse djur or dȳr , Gothic dius , Old Saxon dier , and Old Frisian diar . This general sense gave way to
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