Ring species
What is a cline forming a circular shape forming called?
ring species
When does Allopatric occur
Once after a population becomes geographically isolated
When does sympatric occcur?
It occurs due to change in the niche or lifestyle of the organism
What sudden appearance is this refered to?
A new species
When does this mechanism take action?
Before the egg is fertillzed
A wide geographic area.
Why are they geographically isolated?
Due to environmental events such as geological uplift or change in sea levels
What can develop overtime?
Genetic development, leading to reproductively isolation
What happens to the plant whe. it acquires a extra set of chromosomes?
It becomes reproductively isolated from the parent plant population
When can two related species breed?
At the different times or during the year to produce pollen
What is the offspring ability to reach ,maturity but sterile, meaning they cannot have offspring of their own called?
Hybrid sterility
What happens once a subset of the population is separated from the main population?
The gene flow ceases
Why is it possible for sypatric to be a new species?
By arising without geographical isolation.
What do these polyploid plants must produce?
Asexually
What are reproductive structures that genetically controlled specific to?
A Pollinator
When the end populations meet..
they are reproductively ioslated
What splits a population?
a physical barrier cutting off the gene flow
Why can mechanism occur without physical barrier?
due to ecological specialization
Where are they the most common in?
Plants known as polyploidy
What type of isolating barriers do Prezygotic provide?
they prevent mating or fertilization happening in the first place
When does gene flow occur
step by step around the ring
What does Allopatric format?
due to geological or physical population
What evolution is sympatric apart of?
from a single ancestral species as they inhabit thee same geographical specie
The polyploidy organism can often self fertilize but can't .. ?
cannot Interbreed with the orginial parent population
What can unique mating prevent?
They can prevent cross-species mating.