Download Convergent - Divergent Coevolution and Punctuated

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When a species diverges over time into two
different species, resulting in a species becoming
less like the original one
- Live in different ways than the common ancestor
- Caused by migration or nearby extinction of a
nearby environment
- Prime example are the dinosaurs
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When unrelated organisms evolve similarities
when adapting to similar environments
- Live in the relatively same way as each other
- Emus, rheas, and ostriches are prime
examples of convergent evolution
No Common ancestor involved
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The importance of these types of evolution is
generating variation, as well as species
performing their niche in their environment.
As every species has a role to play, these
types of evolution ensure that these are
carried out.
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An adaptive radiation generally means an
event in which a lineage rapidly diversifies,
with the newly formed lineages evolving
different adaptations.
Different factors may trigger adaptive
radiations, but each is a response to an
opportunity.
Best exampleDarwin’s Finches
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Gradual- slow changes to an organism that
accumulate over time
Punctuated- long periods of stability with
abrupt evolutionary changes happening
rapidly.
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Two organism evolve together due to a
dependence on each other.
The term coevolution is used to describe cases where two (or more) species reciprocally affect each
other’s evolution. So for example, an evolutionary change in the morphology of a plant, might affect
the morphology of an herbivore that eats the plant, which in turn might affect the evolution of the
plant, which might affect the evolution of the herbivore...and so on.
http://evolution.berkeley.edu/evosite/evo101/IIIFCoevolution.shtml
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Two Anemone species
◦ One is polyploidy
Multiple sets of chromosomes
due to non separation of
chromosomes in meiosis.
Affects evolution of a new
species because the different
organisms will not crosspollinate.
Aneuploidy- an abnormal
number of chromosomes. The
number of chromosomes are not
an exact multiple for the
monoploid number. Can be too
many or too few chromosomes.