Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
15 Cards in this Set
- Front
- Back
|
What is a species?
|
Species is a group of populations that mate with one another to produce fertile offspring.
|
|
|
What is speciation?
|
Speciation is the formation of a new species.
|
|
|
Why are species reproductively isolated?
|
Species are reproductively isolated due to genetic differences.
|
|
|
How many years can speciation range from?
|
4,000 (fish) to 40,000 (beetles)
|
|
|
How is speciation caused?
|
Genetic changes must reproductively isolate two sub-populations of a single species to cause speciation.
|
|
|
What is the main difference between evolution and speciation?
|
The change in allele frequency (evolution) does not always result in a new species (speciation).
|
|
|
What is the Allopatric Speciation Model?
|
The Allopatric ("Other Fatherland") Speciation Model:
a physical barrier separates a population into two sub-populations so that each sub-population-- inhabits a different environment, can't mate, and thus can't exchange alleles with the other adapts to its new environment by natural selection becomes reproductively isolated from the other due to one or more genetic changes related to adaptation |
|
|
What is the Sympatric Speciation Model?
|
The Sympatric ("Same Fatherland") Speciation Model:
Genetic differences cause a sub-population to become reproductively isolated from its parent population that inhabits the same area. (prefer a new habitat; prefer a new food source) |
|
|
What is hybridization?
|
Hybridization can initiate sympatric speciation. Related species inter-breed to produce hybrid offspring.
|
|
|
What is intersexual selection?
|
Intersexual (between the sexes) selection is natural selection that occurs when females prefer males with specific traits.
|
|
|
What is intrasexual selection?
|
Intrasexual (within the same sex) selection occurs when males compete directly with other males in order to mate with other females. (huge antlers, large peacock feathers)
This usally results in smaller, less aggressive males. |
|
|
Speciation results from changes in one or more ______.
|
genes
|
|
|
What promotes allopatric speciation?
|
Geographic physical barriers such as man-made buildings and structures promote allopatric speciation.
|
|
|
What promotes sympatric speciation?
|
The sympatric speciation process can begin when a sub-population becomes reproductively isolated from its parent population that inhabits the same area.
|
|
|
Which factors can cause sympatric speciation occur in plants?
|
An individual has double the normal chromosome number.
This individual only can mate with itself or other such polyploids. The offpsring can't mate with individuals with normal chromosome number. This individual becomes reproductively isolated. |
