15.3 Evolution in Action. Standards CLE 3210.5.5 Explain how evolution contributes to the amount of...

15.3 Evolution in 15.3 Evolution in ActionAction

StandardsStandards

CLE 3210.5.5 Explain how evolution contributes to the amount of biodiversity

CLE 3210.5.3 Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.

How does evolution How does evolution work?work? Natural Selection can work in several ways:Natural Selection can work in several ways:

Convergent Evolution: the process by which unrelated species become more similar as they adapt to the same kind of environment

Divergent Evolution: the process by which two or more related but reproductively isolated populations become more and more dissimilar

Co-Evolution: the process by which two or more unrelated species evolve together because of a symbiotic relationship.

Convergent EvolutionConvergent Evolution

How it happens:How it happens:

Example:Example:

Two genetically different species adapt to the same environment in similar ways resulting in similar phenotypes.

Convergent Convergent EvolutionEvolution

Leads to Leads to analogous analogous structures:structures:

Divergent Evolution

How it happens:

Adaptive Radiation:

One species branches off into two or more different species due to changes in environment or behavior.

an evolutionary pattern in which many species evolve from a single ancestral species

Divergent EvolutionDivergent Evolution

Leads to Leads to homologouhomologous s structures:structures:

Co-Evolution

How it happens:When two different species are dependent on each other; if one changes the other must adapt or go extinct.

Artificial Selection

Natural Selection = environment determines desirable traits

Artificial selection = humans determine desirable traits

Exit Ticket

m.socrative.com

Room: stewart348

Compare and contrast natural selection with artificial selection