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AP Enviro



Unit 2

2.6 Adaptations

1 min readapril 29, 2020

Joshua Nielsen


  • Adaptations

  • Traits

  • Evolution

  • Survival of the Fittest

  • Allopatric Speciation

  • Sympatric Speciation

  • Reproductive Isolation

Adapt to the Surroundings

In order for a population to live in an ecosystem, they must have the traits (genes). Its a case of Survival of the Fittest: those that have the right genes for the ecosystem, tend to live longer.


Image courtesy of Pixabay

As the ecosystems change, so too must the populations that live in them, or perish. Evolution is inevitable. Populations with a diverse gene pool, have a better chance of survival when ecosystem changes occur. Not all members of the population may have the genes necessary to adapt to the change, but if enough do then they may pass this on to the offspring. Those that don’t, won’t and those genes die out.

Reproductive Isolation

Populations may diverge from the original due to changes in the environment. Reproductive isolation is when two populations are no longer able to reproduce with each other. If there is a physical barrier between them (a road cutting through a forest), this is allopatric speciation.


Image courtesy of Pixabay

However, if the populations are in the same area but do not reproduce, this is sympatric speciation. The latter may be because reproduction times are different (early bird vs night owl) or seasons are different for the two populations.

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Unit 1: The Living World: Ecosystems

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