Patterns Of Evolution Flashcards
When is coevolution most likely to occur?
When two different species have close ecological interactions with one another.
List three ecological relationships in coevolution.
- Predator-prey/Parasite-host.
- Mutualism
- competition
Key idea of adaptive radiation…
Adaptive radiation is diversification among descendants of a single ancestral group to occupy different niches.
The three principles about the dispersal and distribution of land animals?
- When very closely related animals were present at the same time in widely separated parts of the world, it’s highly probable that there was no barrier to their movement in between the localities in the past.
- The most effective barrier to movement of land animals (especially mammals) was a sea between continents.
- The scattered distribution of living species can be explained by migration out of their original range or extinction in regions between the current populations.
Key idea of Convergent evolution…
Convergent evolution describes the process by which species from different evolutionary lineages come to resemble each other because they have similar ecological roles, through which natural selection can shape them to have similar adaptations.
What are structures that look similar due to convergent evolution called?
Analogous structures (also called homoplasies structures).
What are Analogous structures in terms of Convergent evolution?
Analogous structures are those that have the same function, and often the same appearance, but are quite different organs.
Key idea of divergent evolution…
The diversification of an ancestral group into two or more species in different habitats.
What are the two rates of evolution?
Gradualism and punctuated equilibrium
Key idea of the rate of evolution…
The fact that new species may for gradually over a long period of time or may appear relatively suddenly.
What is gradualism?
Phyletic gradualism assumes that populations slowly diverge by accumulating adaptive characteristics in response to different selective pressures.
What is punctuated equilibrium?
Punctuated equilibrium is where a species stays in long periods of stasis, where these periods are punctuated by short bursts of evolution.
Key idea of convolution…
Coevolution involves the reciprocal evolution of species that have close ecological relations ships, such as those involving mutualism, competition, or exploitation.
