| The fossil record gives a satisfactory record as to how the elephant probably evolved over some 40 or so million years. 37 million years ago, the stubby, short-snouted Moeritherium appeared, built for a life feeding on aquatic plants in the forest. Its branch is not thought to be directly ancestral to elephants, though Moeritherium would have been a close relative of the ancestral elephant. Later on, the lower jaw of these animals would grow greatly in size, as to help brush off vegetation. The deinotheres, which appeared later, had comparatively shorter jaws, like today's elephants. This may be because the deinotheres also had a more specialised trunk, as the leaves they had been feeding on were beginning to lose nutritional value, so a trunk would be useful to cram as much plant food in as possible. Larger elephants may have been selected by nature, as they were better at getting more food, protecting themselves, and storing the food. Elephants would diversify into a number of different genera - Elephants of the Northern Hemisphere would grow a thick layer of fur, leading to the mammoths - a lineage that lasted some 6 million years before a rapid extinction, perhaps caused by a lack of sustainable plant food after the end of the last Ice Age. On some islands, where elephants reached, they would, over millions of years, become greatly smaller in size, as for a lack of resources. The last dwarf-elephant died out some 10,000 years ago, for reasons unclear. For what number of elephant species once existed on Earth, only three or so remain today. | The fossil record gives a satisfactory record as to how the elephant probably evolved over some 40 or so million years. 37 million years ago, the stubby, short-snouted Moeritherium appeared, built for a life feeding on aquatic plants in the forest. Its branch is not thought to be directly ancestral to elephants, though Moeritherium would have been a close relative of the ancestral elephant. Later on, the lower jaw of these animals would grow greatly in size, as to help brush off vegetation. The deinotheres, which appeared later, had comparatively shorter jaws, like today's elephants. This may be because the deinotheres also had a more specialised trunk, as the leaves they had been feeding on were beginning to lose nutritional value, so a trunk would be useful to cram as much plant food in as possible. Larger elephants may have been selected by nature, as they were better at getting more food, protecting themselves, and storing the food. Elephants would diversify into a number of different genera - Elephants of the Northern Hemisphere would grow a thick layer of fur, leading to the mammoths - a lineage that lasted some 6 million years before a rapid extinction, perhaps caused by a lack of sustainable plant food after the end of the last Ice Age. On some islands, where elephants reached, they would, over millions of years, become greatly smaller in size, as for a lack of resources. The last dwarf-elephant died out some 10,000 years ago, for reasons unclear. For what number of elephant species once existed on Earth, only three or so remain today. |
| The two species of African elephant are about the same size, though the forest elephant can have much larger tusks. As a rule, the Asian elephant is the smaller species of the three, albeit only by a few hundred centimetres. Consistent amongst elephants is a general body plan – all are quadrupedal, with forelimbs just more extended than their back limbs, and a long trunk at the front of the head. Having a head several metres from the ground, the trunk makes food on the ground accessible, but can also be used to grab food off trees. For such large feet, the elephant walks in a graceful manner, as under the foot is a large, cartiligous pad, which works as a shock absorber, and helps the animals walk silently. Looking at the elephant’s skeleton, one is able to observe that at the base of the foot, the elephant in fact walks on its toes, skeletally speaking. Behind the toes is a large pad of fat, which fills space. Elephants, however, require large amounts of soft ground as so to maintain good health of the foot – as it has been observed that elephants in captivity which live mainly on concrete, or other hard substance, may develop foot disorders, which are uncommon in the wild. If one is to look at the skeleton, however, they will fail to find the most distinguished feature of the elephant – the elongated trunk, as this is consisted entirely of muscle – about 40,000 of them. Nor will one notice another distinguished elephant feature – large tusks. These are made not of bone, but of keratin. Although both male and female African Elephants have tusks, only bull Asian Elephants do, with most Asian Elephant cows essentially tuskless. In recent years, it has been noticed that populations of elephants in Africa are becoming tuskless all together – some believe that this is an evolutionary response to a rise in poaching in recent years – tuskless elephants do not have a reason to be poached. However, this could be a hindrance to the development of bull elephants, which use their tusks in competitive fighting, and foraging. The large ears of the elephant are essentially comprised of thin blood vessels – larger ears give a larger space for heat to be concentrated, to avoid any particular part of the elephant being especially concentrated in heat. Flapping ears allows for blood vessels to come into contact with air, cooling them, and these blood vessels will send cooler blood around the body. As is the case with most herbivores, the elephant’s teeth are on the sides of the mouth. The teeth, unlike other herbivores, form veritable structures, but elephants’ teeth are to last them their entire life, making the loss of such teeth potentially fatal to mature elephants. The body of the elephant is covered in thick, wrinkled, skin, though with sparse amounts of hair. As this is at risk of attack from pests, elephants consistently cover themselves with dust, mud, or water as so to prevent infection from pests. | The two species of African elephant are about the same size, though the forest elephant can have much larger tusks. As a rule, the Asian elephant is the smaller species of the three, albeit only by a few hundred centimetres. Consistent amongst elephants is a general body plan – all are quadrupedal, with forelimbs just more extended than their back limbs, and a long trunk at the front of the head. Having a head several metres from the ground, the trunk makes food on the ground accessible, but can also be used to grab food off trees. For such large feet, the elephant walks in a graceful manner, as under the foot is a large, cartiligous pad, which works as a shock absorber, and helps the animals walk silently. Looking at the elephant’s skeleton, one is able to observe that at the base of the foot, the elephant in fact walks on its toes, skeletally speaking. Behind the toes is a large pad of fat, which fills space. Elephants, however, require large amounts of soft ground as so to maintain good health of the foot – as it has been observed that elephants in captivity which live mainly on concrete, or other hard substance, may develop foot disorders, which are uncommon in the wild. If one is to look at the skeleton, however, they will fail to find the most distinguished feature of the elephant – the elongated trunk, as this is consisted entirely of muscle – about 40,000 of them. Nor will one notice another distinguished elephant feature – large tusks. These are made not of bone, but of keratin. Although both male and female African Elephants have tusks, only bull Asian Elephants do, with most Asian Elephant cows essentially tuskless. In recent years, it has been noticed that populations of elephants in Africa are becoming tuskless all together – some believe that this is an evolutionary response to a rise in poaching in recent years – tuskless elephants do not have a reason to be poached. However, this could be a hindrance to the development of bull elephants, which use their tusks in competitive fighting, and foraging. The large ears of the elephant are essentially comprised of thin blood vessels – larger ears give a larger space for heat to be concentrated, to avoid any particular part of the elephant being especially concentrated in heat. Flapping ears allows for blood vessels to come into contact with air, cooling them, and these blood vessels will send cooler blood around the body. As is the case with most herbivores, the elephant’s teeth are on the sides of the mouth. The teeth, unlike other herbivores, form veritable structures, but elephants’ teeth are to last them their entire life, making the loss of such teeth potentially fatal to mature elephants. The body of the elephant is covered in thick, wrinkled, skin, though with sparse amounts of hair. As this is at risk of attack from pests, elephants consistently cover themselves with dust, mud, or water as so to prevent infection from pests. |
