Lesson 1 Introduction – Overview of Ungulates

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Ungulates are mammals which have hoofs, or structures like hoofs, on their toes. A hoof is simply an enlarged toenail. All such animals belong to the taxonomic group “Ungulata”.

Hippopotamus (Hippopotamus amphibius)

Introduction the unguis is the primary point of contact with the ground. In non-ungulates, other tissues, such as the pads of the There are two parts to a hoof: feet, provide the primary contact point when walking. ■■ The ‘unguis’ - a scale-like plate that forms the top layer and which The hoof is basically modified epidermis is exposed to the air. In humans, and this consists of keratin, which the hard part of the finger nail is thickens and hardens the hoof. There the unguis. are a variety of ungulate ‘hoofed’ animals, and each has different hoofs. ■■ The ‘sub-unguis’ - a soft layer Hoofs continue to grow; in wild, hoofed between the unguis and the tissue ungulates length is managed by daily of the digit (a finger, thumb or toe). foraging and walking. Domesticated animals tend to stand around longer, Non-ungulate mammals may have claws and do not have access to enough or fingernails instead of hoofs. The room to be able to keep their hoofs primary difference between ungulates down naturally, so may require and non-ungulates is whether or not the hoof maintenance which their wild unguis is used in walking. In ungulates, counterparts do not.

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In some ungulates, the pads of the feet, assist in the breakdown of cellulose for ▼ behind the hoofs will touch the ground. fermentation to occur. Suggested Tasks: In others, these pads do not touch the Throughout this course ground. Either way, it is the hoofs that Ruminants are a good example of you will be provided with carry most of the weight of the animal animals with such multi-chambered suggested tasks and reading and as an adaptation this brings a range stomachs, and they usually have four to aid with your understanding. of benefits to hoofed animals. chambers to assist in digestion of plant These will appear in the right material. The food passes through these hand column. Remember: Hoofs play a variety of roles including; four chambers gradually to fully allow these tasks are optional. The shock absorption from the ground, digestion to take place. Once ingested more you complete, the more weapons for protection, and tools for and chewed, the food passes down the you will learn, but in order to digging. Many ungulate mammals run oesophagus of the ruminant species, complete the course in 20 (deer, horses), or carry significant then into the first chamber of the hours you will need to manage weight loads (elephants, hippopotami), stomach, known as the rumen. It then your time well. We suggest and hoofs help reduce damage to the follows into the reticulum, the omasum you spend about 10 minutes foot through shock absorption. They can and then the fourth chamber, the on each task you attempt, and also serve protective functions for the abomasum. The first three chambers no more than 20 minutes. foot. Some ungulates also use hoofs for digest the carbohydrates, and quite digging and foraging to locate food and often the food is regurgitated to be water. Defensively, hoofs are used both chewed and then swallowed again for Learn More ››› within a given species, and to defend added digestion. Once the food passes against predators. through the four stomachs, it then Suggested Tasks enters the duodenum, the first section of the small intestine. Camelids all have a Ungulates consist of two groups Digestion three-chambered stomach which works of animals - odd toed ungulates in the exact same way as a four, and and even toed ungulates. And Most ungulates are herbivores, with are also able to ruminate. there are more even toed the exception of pigs and peccaries ungulates than odd toed ones. which are omnivores that eat small rodents, insects, and bugs. The Take a guess at how many majority of ungulates have evolved their species of odd toed ungulates digestion in a way that allows them to and even toed ungulates decompose chemicals in plants which there are, and write down other types of animals may find difficult your answers. to digest. Although not all ungulates are ruminants, many – including hyraxes Now go online and search to – have multi-chambered stomachs see if you were close. Search which help digest this plant matter. using phrases such as “list All perissodactyl (odd-toed) ungulates of ungulate animals”, “how are known as hindgut fermenters, and many species of ungulates they have a simple stomach with a are there?” or “number of lot of the digestion taking place in the ungulate animal species”. caecum. The digestive tracts of most ungulates (except pigs), are specifically Are you surprised by what designed to digest nutrients from plant Cow Grazing you found? materials, and contain microbes which

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In perissodactyl species the digestive a thick, sticky fluid; and parietal cells, system consists of a simple stomach which produce hydrochloric acid to which consists of walls made up of assist in protein digestion. involuntary muscle. Food enters the stomach to be processed, then passes All ungulates have teeth which are into the small intestine. Sphincters, specialized for chewing plant material. on both the entrance and exit to the They have large, square molars and stomach, contract and relax to control incisors designed to pluck and tear plant the flow and passage of food. The lining matter. Their jaws are modified to allow of the stomach contains gastric glands lateral (side-to-side) movement, as well which are lined by three types of cells: as up and down movement for maximum chief cells which produce digestive grinding action. enzymes; mucous cells which produce

Gerenuk (Litocranius walleri)

Behaviour exhibit grazing behaviours, feeding on grasses, and they will graze for long Most species exhibit typical foraging periods of time. Other ungulates are behaviours, even when not in need of browsers and these feed on shrubs, food. Domestic animals, for example, trees, vines and fruit. Giraffes are are fed regularly yet will still spend a lot a good example of a browser, and of time moving about in their enclosure deer are a good example of grazing as if they are foraging. Some ungulates behaviours. Ungulates spend much

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of their time feeding to obtain all the Grandorder: nutrients they can from the plant Learn More ››› materials, and even the omnivorous pigs Ungulata and peccaries spend most of their time Suggested Tasks foraging for roots and insects. Weaned Ungulates are all classified within the infants commonly exhibit oral activity grandorder, Ungulata. Ungulates have Which ungulates do you such as chewing. evolved features that are adaptive think are amongst the fastest for life on open grasslands. A good land animals? Social behaviours of ungulate animals example is long legs which help them vary between species, and are not solely run away quickly from predators. To Write down three possibilities related to the evolution or biology of the lengthen the legs, ungulates evolved and then check online to see if animals. Ecological factors also play a unguligrade locomotion. In this type of you were right. part in ungulate social groupings. movement, only the hoof is in contact with the ground. This type of motion is a Try searching for “world’s Reproductive behaviour of ungulates specialised feature of running animals, fastest hoofed animals”, “top 10 varies between species but they do including horses and deer. fastest land animals”, or use a exhibit some similarities. Both male and similar phrase. female must have full sexual intercourse It is important to remember that the for reproduction to occur, and all hoof is essentially a toe tip, part of an ungulates are eutherian (previously anatomically enlarged toe. Deer, sheep, known as placental) mammals. and goats walk on two toes; rhinos, Therefore, the female will give birth to tapirs and some extinct horses walk live young, and the offspring are raised either on three toes or on one toe (living and nursed with milk which is secreted horses). The remaining toes not used from the mammary glands. for walking are either reduced, as in pigs and tapirs, or completely lost, as in The Ungulate Brain and rhinos and most ruminants. Behaviour

The ways in which ungulates use resources (e.g. for food and shelter) are relatively simple across all ungulates; but social behaviours are extremely varied. Some ungulates have far more complex social behaviours than others and brain size tends to be greater in these animals.

Ungulates in the wild typically feed by foraging. Domestic and captive animals, which lack the opportunity for wider foraging, often display abnormal oral behaviours such as biting, chewing, and tongue rolling. Goat (Capra hircus)

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The other major types of movement are ■■ Perissodactyla - includes: Horses, plantigrade and digitigrade. Humans are Rhinoceroses, Tapirs plantigrade, with the heel striking first in each stride. Bears, opossums, racoons ■■ Tubulidentata - includes: Aardvarks and most other vertebrates that walk but seldom run are plantigrade. Conversely, ■■ Hyracoidea - includes: Hyraxes (or running dinosaurs, birds, carnivores and Conies) extinct ancestors of hoofed mammals use digitigrade movement, increasing ■■ Proboscidea - includes: Elephants leg length by standing on and walking on their digits – that is, toes or fingers. ■■ Sirenia - includes: Manatees and Dugongs All animals in the grandorder Ungulata have hoofed feet, except for those which As with many biological specimens, are aquatic (the Cetaceans, which the taxonomy – or classification – include dolphins, and the Sirenes, which of ungulates changes according include manatees). to recent discoveries across fields such as evolutionary biology and There are seven separate orders as genetics. Recent research suggests follows: that cetaceans (dolphins, porpoises, and whales) may have evolved from ■■ Artiodactyla - includes: artiodactyls (even-toed ungulates). Hippopotami, Deer, Giraffe, Sheep, Fossil evidence supports the possibility Cattle, Antelope, Camelids of a shared ancestor and, as such, some scientists now use the super ■■ Cetacea - includes: Dolphins, order, Cetartiodactyla to demonstrate Porpoises, Whales this relationship.

Antelope are one of many Artiodactyl ungulates

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