Evolution of Elephants

What is an elephant

Elephants are mammals that have the life span of up to 70 years. Elephants are herbivores, their main food source are roots, plants, fruits, grasses, and bark. An adult elephant eats up to 140 kg in 1 day. An elephant’s main habitat are savannas, grasslands, and forests. They dominate the deserts, swamps, and highlands in tropical and subtropical lands of Africa and Asia.

Different types of elephants

The 2 main species of elephants are the Asian and African elephants. Both of these species consist of many wider types of elephants within the species.

Colours of elephants

Elephants mainly have grey skin but after the African elephants have been around the coloured mud they become a brown, reddish colour. Most elephants have depigmentation patches on their ears and foreheads.

Habitat

The African elephants live in the rain forests of Central and Western Africa. They also live in the Sahel desert of Mali. The Asian elephants live in the wet to dry rain forests and the grasslands. Asian and African elephants have adapted to their habitat and have learnt to survive on the resources provided from their habitat.

When were they discovered ?

Elephants were discovered 35 million years ago. The first animal discovered that developed into an elephant was called Paleomastodon. The mammal was around the same size as a cow and it had tusks and a short trunk. Modern elephants only evolved about 5 million years ago.

Where were they discovered ?

Elephants originated from Africa and India. Scientists had discovered fossils in 2010 from the elephants oldest relatives tracing back to 60 million years. These fossils were found in Morocco.

Evolution of the trunk

Trunks

The ancestors of elephants relied on rummaging on the ground for food. The pair of tusks prevented them from being able to open their mouths to reach the food. The trunk evolved over time to allow the ancestors to reach the food on the ground. The trunk is also used to allow the elephants to keep their heads up and watch for prey. The long trunk is useful in this way as it can reach to food without the elephants having to bend their head down to only see the ground.

Evolution of tusks

Tusks

Elephants are beginning to evolve without tusks due to poaching. This evolution is an un-natural selection as it is caused by poaching. The poaching of elephants is causing pressure to the elephants which is the main causes of elephants evolving without tusks.

Evolution of size

Size

The sizes of elephants have evolved based on their ancestors. Their ancestors have developed in size which allowed the elephants to develop in size.

Other Animals

No animals have evolved from an elephant. And elephant has evolved from other mammals but no animals have evolved from an elephant.

Main relatives

80 million years ago the genetic linage of elephant ancestors split from primates. This is the cause of evolution between the elephant’s ancestors. Elephants and their extinct relatives share a connection with manatees, dugongs and sirenians.

What did their relatives look like

The elephant relatives all look very similar as they share skin colour, size, and body shape. The evolution of the trunk is the biggest growth on the animals. The trunks evolved very quickly over time from the first ancestor. The elephant tusks have also evolved in shape to allow the mammals to access their food easier from the ground.

Fossils from the elephant’s relatives have been discovered. These fossils trace back to 60 million years ago.

When were the relatives discovered

The links

The evidence that proves the elephant’s ancestors are through the genetic lineages. Genetic lineages are a series of mutations that prove genetic ancestry. The ancestors of the elephants such as manatees, sirenians and dugongs all have the same genetic lineages. 80 million years ago the genetic lineage elephants split from primates. Based on research, study has shown that the closest ancestors to elephants based on genetic lineages are manatees, dugongs and hyraxes.

Natural selection is the adaption of organisms which help them survive in different habitats. Natural selection also involves the reproduction of organisms based on their characteristics. Natural selection shows the changes in evolution between organisms.

What is natural selection ?

Natural selection affects animals as it is adaptation to the habitat. The organisms adapt to their environment to survive. If natural selection did not occur animals would not be as developed and would not survive in their habitats.

Effect on animals

Effect on elephants

Natural selection has affected elephants as they have adapted to their environment and have developed trunks to eat. If elephants did not go through natural selection they would not gave long trunks and could not eat their main food source.

Comparisons

The ancestors of an elephant are much smaller and only have small trunks. The trunks of the ancestors developed very quickly based on natural selection. The size of elephants has also developed over time. The shape of the tusks has slightly developed over time, the tusks on the ancestors had always been facing up and over time they would face higher and lower.

In 2018, Adelaide university research the DNA of an elephant and were able to connect the DNA with the woolly mammoth. The connections show that the elephant and woolly mammoth had split into different species 60 million years ago. There was a large variety of interbreeding throughout the ancestors and that had eventually developed an elephant species.

DNA Connections

Differences

The DNA connections between the elephants and their ancestors have some difference which proves some appearance difference between the animals, but some of the DNA is similar as is their appearance. The sizes of the first ancestors is one of the main differences. The size of the species developed over time from around the size of a cow to the size an elephant is today. One of the other main differences is the trunk size. The trunk size had to develop based on natural selection. The trunk has to develop as the animals needed to survive by eating. The first ancestors struggled to eat the plants and grasses of the ground, the trunk developed in size, so the animals were then capable of eating off the ground.