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Flashcards in Evolution Deck (6)
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Define evolution.

The change in organisms over many generations.


What did Darwin observe?

Members showed variation
Individuals had the potential to produce large numbers of organisms but the number of adults remained constant
Resources were limited


What did Darwin deduce?

There is a ‘struggle for existence’ with only the fittest surviving
Those that survive reproduce and their offspring have the characteristics they need to succeed.
In time a group of individuals undergo many changes and becomes sufficiently distinct to belong to a new species.


Why is natural selection a continuous process?

If the environmental conditions change, the features needed to survive in it change so it is continuous n


What is natural selection and evolution, described in modern terms)

There is competition for limited resources and those individuals that have alleles providing a better adapted phenotype reproduce more successfully. They pass the alleles that produce the phenotype to their offspring and so this continues over generations. The average phenotype changes.


What are 2 types of evolutionary product?

Adaptations are features used in an original form
Expaptations are structures that appear to have their original use modified.