The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The...

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Transcript of The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The...

Page 1: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.
Page 2: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.

The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other species. The giraffids evolved from a 3 metres (9.8 ft) tall antelope-like mammal that roamed Europe and Asia some 30-50 million years ago.[6]The earliest known giraffid was Climacoceras, which still resembled deer, having large antler-like ossicones. It first appeared in the early Miocene epoch. Later examples include the genera Palaeotragus and Samotherium, which appeared in the early to mid-Miocene. They were both tall at the shoulder, and had developed the simple, unbranched ossicones of modern giraffids, but still had relatively short necks.[7]From the late Pliocene onwards, the variety of giraffids drastically declined, until only the two surviving species remained. The modern genus Giraffa evolved during the Pliocene epoch, and included a number of other long-necked species, such as Giraffa jumae, that do not survive today.[7] Alan Turner proposes, in the 2004 book Evolving Eden, that giraffe ancestors initially had a dark coat with pale spots, and that the spots gradually became star-shaped, before eventually forming the reticulated pattern found today.[8] The modern species, Giraffa

camelopardalis, appeared during the Pleistocene 1 million years ago].citation needed[

The evolution of the long necks of giraffes has been the subject of much debate. The standard story is that they were evolved to allow the giraffes to browse vegetation that was out of the reach of other herbivores in the vicinity, giving them a competitive advantage.[7] However, an alternative theory proposes that the long necks evolved as a secondary sexual characteristic, giving males an advantage in "necking" contests (see below) to establish dominance and obtain access to sexually receptive females. This theory notes that giraffes frequently feed from relatively low-lying shrubs, and that the necks of males are significantly longer than those of females.[9] However, this theory is not universally accepted, and some of the data supporting it has recently been challenged, lending support to the original proposal that neck length is related to browsing habits

Page 3: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.

                         From cave paintings it is believed that the equid from which modern horses are derived resemble the modern Przewalski Horse. The large strong heads and erect manes depicted in these paintings bear a striking resemblance to this modern breed. The first domestication of the horses was probably in the steppes of central Asia between 3000 and 4000 B.C. These first animals were kept for meat and milk. As early man became more mobile undoubtedly horses began to be used as pack animals.                 Oxen were being used in the Middle East at approximately 4000 B.C. for plowing. Progressively they were used on sleds, which were eventually mounted on rollers, with the final evolution of wheels. Early in the 3rd millennium B.C. there is archeological evidence that vehicles drawn by equid, generally onagers or ass hybrids, were being used in warfare. As horses from the north became more numerous the carts moved to the familiar two-wheeled chariot with spoked wheels. Due to his greater speed the horse rapidly replaced other equid as harness animals.

Page 4: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.
Page 5: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.

•For other uses, see Horse (disambiguation).•Domestic horse

Conservation statusDomesticatedScientific classificationKingdom:AnimaliaPhylum:ChordataClass:MammaliaOrder:PerissodactylaFamily:EquidaeGenus:EquusSpecies:E. ferusSubspecies:E. f. caballusTrinomial nameEquus ferus caballusLinnaeus, 1758[1]Synonyms48, listed hereThe horse (Equus ferus caballus)[2][3] is a hoofed (ungulate) mammal, a subspecies of one of seven extant species of the family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today. Humans began to domesticate horses around 4000 BC, and their domestication is believed to have been widespread by 3000 BC; by 2000 BC the use of domesticated horses had spread throughout the Eurasian continent. Although most horses today are domesticated, there are still endangered populations of the Przewalski's Horse, the only remaining true wild horse, as well as more common feral horses which live in the wild but are descended from domesticated ancestors.

•There is an extensive, specialized vocabulary used to describe equine-related concepts, covering everything from anatomy to life stages, size, colors, markings, breeds, locomotion, and behavior. Horses are anatomically designed to use speed to escape predators, and have a well-developed sense of balance and a strong fight-or-flight instinct. Related to this need to flee from predators in the wild is an unusual trait: horses are able to sleep both standing up and lying down. Female horses, called mares, carry their young for approximately 11 months, and a young horse, called a foal, can stand and run shortly following birth. Most domesticated horses begin training under saddle or in harness between the ages of two and four. They reach full adult development by age five, and have an average lifespan of between 25 and 30 years.

Page 6: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.
Page 7: The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other.

Name: Malak AgloneClass:6th grade

Teacher :lana Fashho