Please enable JavaScript.
Coggle requires JavaScript to display documents.
10.3 U4 SPECIATION (How Poliploidy is related to Speciation? (Tetrahaploid…
10.3 U4 SPECIATION
Can be defined by
-
Examples
allopatric speciation
The most famous example for this type of speciation is the galapagos finch; the species varies in terms of it's beak. For example, the galapagos finch that lives in island A has a big beak that enables them to capture insects easily while galapagos finch that lives in island B has thinner and longer beak that enables them to drink water from cactus plant without coming in contact with the cactus' sharp torns
-
sympatric speciation
Sympatric speciation mostly occurs in plants species where parent plants produce offspring that are polyploid. The offspring live in the same environment as their parents but are reproductively isolated.
However, this is an example of sympatric speciation in animals
-
Process and Mechanisms
Allopatric Speciation
divergence of species due to geographical barrier where the species are physically isolated
This will results in the species to evolve separately as it prevents them to mate with one another.
This will reach a degree of genetic divergence due to they can no longer interbred
Example of physical barrier are mountains, desert and rivers.
The barrier can be porous as in a few individuals can cross the barrier to mate, but it can still be considered allopatric as long as the gene flow between the soon to be species are greatly reduced, but not necessarily zero.
Sympatric Speciation
Sympatric Speciation divergence of species within the same geographical location (i.e. without a physical barrier)
- may result from the reproductive isolation of two populations as a result of genetic abnormalities ---> prevents successful reproduction with any organism lacking the same error
2.If meiotic cells fail to undergo cytokinesis, chromosomal number will double in the gamete (e.g. diploid instead of haploid) --->
This will result in offspring that have additional sets of chromosomes (polyploidy)
refer to *tetrahaploid
-
-
-
-
-
-
-
-