Biology B3

Adaption to different environments increases survival of the fittest as animals will be able to adapt to certain living conditons thus giving them a better chance in surviving through better access to food and possibly beter and more accurate features. For example, bigger ears to aid hearing, which can help animals escape quicker from predators.

Selective breeding is when humans are able to modify the features of the animal physically to change specific features to aid them. For example, breeders may only choose to breed the cows, which produce the most milk. In this way, the next generation of cows would naturally be able to produce more milk. Unlike natural selection, this will not benefit the cow but the humans because they will be making more money.

Even within some species, animals are able to have different adaptations and physical features. This is when groups of organisms of the same species become isolated from each other and thus can't breed with each-other. As they will be in different environments, they will adapt to different conditions and eventually after natural mutations, they will become 2 different species.  

Evolution - the start of life:

The idea of evolution was hypothesised by Charles Darwin. He observed the finches in Galapagos islands. There were different groups far from each other on other sides of the island and showed variations in size, beaks and claws.

There was also another person, Lamarck, who argued that if a characteristic was used by an animal more, it would become more developed.  Therfore meaning that even future generations would be born with the same characteristics. This was proved to be incorrect as the characteristics wouldn't have a genetic basis and thus wouldn't have anything to do with the animal's offspring.   

Life on Earth began about 3500 million years ago. Early life forms evolved and even more species were there. However, some species became extinct due to weather conditions or large numbers of predators. Apes are the animals that evolved to become the most complex creatures on Earth, humans!

Scientists are able to prove evolution from fossil records and DNA. Fossils are the compressed bone structures of animals (these can sometimes trap parts of some plants too, which can also show evoluton in plants). However, these take over millions of years to form and at the present are used as fuels to generate electricity in power stations. DNA can be examined in order to identify the characteristics of the creature that once lived. Even though DNA mutates over time, ther are still some parts…


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