Extinction 0.0 / 5 ? BiologyEvolution, extinction and natural selectionGCSEAQA Created by: asho glenoCreated on: 14-04-15 13:41 We are currently in the 7th mass extinction phase the Earth has seen meaning... more tahn 10% of the species currently alive today will become extinct within a century 1 of 12 Reasons for Extinction - 1. The environment changes too quickly... 2. A new predator kills them 2 of 12 3. A new disease kills them... 4. They can't compete with another new species for food 3 of 12 5. A catastrophic event happesn - like a volcano errupting-... A new species develops 4 of 12 Speciation is a group of similar organisms that can... reproduce to give fertile offspring 5 of 12 It is the development of a new species and occurs when populations of... the same species become so different that they can no longer produceysicl fertile offspring 6 of 12 Isolation is where populations of a species are sperated and this can happen due to... a physcal barrier 7 of 12 Floods and earthquakes can cause barriers that geographically isolate some individuals from... the main population and conditions on each side will be slightly different 8 of 12 There may be different climates on each side and because the environment is... different, different charecteristics will become more common due to natural selection 9 of 12 1. Each population shows variation because... they have a wide range of alleles 10 of 12 2. In each population, individuals with characteristics that make them better adapted to... their environment have a better chance of survival and breed successfully 11 of 12 3. The alleles that control the beneficial characteristics are more likely to... be passed on to the next generation 12 of 12
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