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Calves are born with only a thin layer of blubber, but some species compensate for this with a covering of fine, downy hair known as lanugo. Three calves died moments after their birth, but two survived for several years.

Porpoise – Wikipedia

Amazon river dolphin Downolad. In humans, the middle ear works as an impedance equaliser between the outside air’s low impedance and the cochlear fluid’s high impedance. Harbour porpoises have historically been kept in captivity, under the assumption that they would fare better than their dolphin counterparts due to their shallow-water habitats.

They have no upper incisors, but rather a hard upper gum pad, against which their lower incisors bite to tear grass stems and leaves. The gnus and gazelles of East Africa perform some of the most impressive mass migratory circuits of all mammals.

Not surprisingly for animals with long, slender yet powerful legs, many antelopes have long strides and can run fast.

Short-finned pilot whale G. As with most mammal hybrids, the less closely related the parents, the cqptivity likely the offspring will be sterile. Retrieved 29 August Northern right whale dolphin L. Southern right whale E. As well as this, the eyes of a porpoise are placed on the sides of its head, so their vision consists of two fields, rather than a binocular view like humans have.

This page was last edited on 4 Februaryat Males more commonly use their horns against each other than against another species. The most obvious visible difference between the two groups is that porpoises have shorter beaks and flattened, dowmload teeth distinct from the conical teeth of dolphins.

Billions of wild and semiwild animals live in captive conditions very different from their ancestral pdc.

Females have mammary glands, but the shape of a newborn calf’s mouth does not allow it to obtain a seal around the nipple— instead of the calf sucking milk, the mother squirts milk into the calf’s mouth. With some species possessing spectacular leaping and evasive skills, individuals may escape. In other projects Wikimedia Commons.

Some species log out of the water, which may allow then to travel faster, and sometimes they porpoise out of the water, meaning jump out of the water. The tube in the head, through which this kind fish takes its breath and spitting water, located in front of the brain and ends outwardly in a simple hole, but inside it is divided by a downward bony septum, as if it were two nostrils; but underneath it opens up again in the mouth in a void.

Antelopes are a common symbol in heraldrythough they occur in a highly distorted form from nature. Gazelles and springbok are known for their speed and leaping abilities. Bovidae Mammals of Africa.

This breeding success proved that porpoises can be successfully bred in captivity, and this could open up new conservation options. Retrieved 30 August They live in a forest environment with patchy resources, and a male acptivity unable to monopolize more than one female due to this sparse distribution.

They may also eat benthic invertebrates. Numerically, most live in the African savannahs. This, however, may be a later folk etymology. There is, however, no scientific evidence that the horns of any antelope have any change on a human’s physiology or characteristics.

Both dibatags and gerenuks habitually stand on their two hind legs to reach acacia and captivuty tree foliage. The harbour porpoise was one of the most accessible species for early cetologistsbecause it could be seen very close to land, inhabiting shallow pdg areas of Europe. Males play no part in rearing calves. The size and shape of antelope horns varies greatly.

The Encyclopedia of Mammals.

Furthermore, understanding the mechanisms that predispose captive populations to thrive or fail can yield new insights into how animals respond to HIREC.

New Approaches to downlload Study of Marine Mammals.

These parallels between HIREC and captivity suggest that certain species could be in double jeopardy: This mode of reproduction produces few offspring, but increases the probability of each one surviving. The calves are weaned at about 11 months of age. Arco Publishing Company, New York.

In order to try to prevent extinction, the Mexican government has created a nature reserve covering the upper part of the Gulf of California and the Colorado River delta.

Perrin; Bernd Wursig; J. This article is about the herbivorous mammals. Acute senses of smell and hearing give antelope the ability to perceive danger at night out in the open when predators are often on the prowl. Antelope have a wide variety of coverings, though most have a dense coat of short fur. This bizarre and inaccurate form was invented by European heralds in the Middle Ages, who knew little of foreign animals and made up the rest.

Nothing is known about the diet of the spectacled porpoise. India is home to the nilgaichinkarablackbuckTibetan antelopeand four-horned antelopewhile Russia and Central Asia have the Tibetan antelope, and saiga.

The Chinese Academy of Science ‘s Wuhan Institute of Hydrobiology has been working with the World Wildlife Fund to ensure the future for this subspecies, and have placed five porpoises in another well-protected area, the He-wang-miao oxbow.

Within one generation, captive-reared animals may show beneficial phenotypic changes e. Ziphiidae Beaked whales Downloae Arnoux’s beaked whale B. Antelope are ruminantsso have well-developed molar teethwhich grind cud food balls stored in the stomach into a pulp for further digestion.