Examine the mechanisms of evolution.
Describe how natural selection results in biodiversity.
Explain why biodiversity is important to continued evolution.
Examine mutations and sexual recombination, which are sources of genetic variation.
Evolution refers to gradual changes in the inherited traits of a population of organisms that occur through successive generations. For evolution to occur a force need to be exerted on a population of species. The ultimate goal of evolution can be thought of as 'enhancement of reproduction'. There are two mechanisms by which evolution occurs:
1) Natural selection: This process relies are three simple rules:
- Variations exist within the population of a given species
- Organisms produce more offspring that can actually survive
- Offsprings are not equal in their ability to survive
Having these three factors in mind, one can explain natural selection in words of Darwin who gives this the term " survival of the fittest". In other words the offspring that has 'fittest' genetic make up (these variations happen at random) have the best chance of survival given very specific conditions. For example, consider Pandas. These animals need a 'thumb' on their hand to be able to grab on to bamboo trees (their major source of food) and eat. Now imagine the time that Pandas were evolving from their family of bears (bears don't have a thumb on their hand!). Those Pandas that happened to have a 'thumb' when the weather became really cold and ...
An overview of evolution and the mechanisms by which it occurs.