Natural Selection Research Paper

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Today you see Elephants as large grayish- brown wrinkly skinned animals with a long trunk and two tusks pointing upwards. Elephant’s tusks and fur have evolved due to environmental changes. Living things that change to adapt to it’s environment then passing on their characteristics to their offspring which is called Natural Selection. Natural selection is one way evolution occurs and is also the reason why elephants change their traits to adapt to their environment. Over time the lineage of the Elephant has changed quite a bit by experiencing natural selection. The environment has changed a lot for the Elephantide from the Ice Ages to the hot sun in Africa. It has shaped the amount of fur a elephant possess and it’s tusk shape and size. …show more content…

The Phosphatherium lived about 60 million years ago and classified as a Proboscidean, which is the same group Elephants belong to (Sources #4 and #5). Scientists have studied the skull and lower dentition (teeth) of the Phosphatherium and have found similarities to Elephant teeth. According to the “New mammal from the Early Eocene of Morocco exemplifying unexpected early diversity of Proboscideans” article written by E. Gheerbrant , J. Sudre , H. Cappetta, M. Iarochène , M. Amaghzaz, B. Bouya, (source #5) it states that ,“The new Ouled Abdoun proboscidean is known mainly by the lower dentition documented by two well preserved dentaries bearing the jugal teeth. The molars are characterized by a bilophodont and true lophodont pattern, very close to Numidotherium and Barytherium (other Elephant ancestors) ones. The new taxon is closer to these genera and more advanced than Phosphatherium in several noticeable features... exemplifying unexpected early diversity of Proboscideans...We report a new primitive proboscidean which is one of the earliest known proboscideans with Phosphatherium from the same locality. This discovery …show more content…

Evolution is the slow process of organisms developing to a more complex form than in the past. I also learned that over the course of evolutionary history, it has been estimated that there have been about 352 species of Proboscideans. All but two (the African and Asian elephants) have died out (Sources #2). It taught me Elephant ancestors are categorized by the direction and movement in the molars (Sources # 1 #4). I think it is really fascinating! One of the main things that are still up for debate is what mammal is really the oldest Elephant ancestor? The eldest recorded one is the Phosphatherium. Some people believe that the Phosphatherium is the oldest ancestor, but I believe that there were older ancestors around Dinosaur time. “In Nature in 1993, palaeontologist Robert Martin of the Anthropological Institute in Zürich, Switzerland pointed out that the fossil record is far from complete. Lineages of animals may have originated millions of years earlier than implied by known records of the earliest-known representatives of any particular group. To put it another way, if a fossil is distinctive enough to show signs of belonging to a particular lineage, then that lineage must already have been in existence for some time. So, although Phosphatherium is very ancient for a member of the elephant lineage, elephantine ancestry probably goes deeper still. Although its earliest representatives did not look much like what