Speciation Flashcards
What does abiotic mean?
Non-Biological factors i.e. Climate
What does biotic mean?
Biological factors i.e. disease
What does niche mean?
The range of resources available and the ability to tolerate conditions.
What are limiting resources?
Light, water, temperature, etc.
What is adaptation?
Outcome of evolution, adapting to specific conditions in order to survive.
What is heterogenity?
Patchiness in; distribution/environmental features/spacial or temporal
What is natural selection?
Traits acquired to survive nature
What is sexual selection?
Traits acquired to survive own species (desirable traits to mates such as strength)
What is adaptive radiaton?
The ability to compete for resources through rapid natural selection - speciation
What is Darwin’s Dilemma?
- If a species descended from other species gradually, then why don’t we see transitional forms?
- Why do we not find fossilised intermediate species?
What is phylogeography?
Looking at large scale processes, phylogeny, genetics, requires a definition of the term species.
What is a species?
A basic unit of taxonomic classification.
Mayr (1942) - “Groups of actually or potentially interbreeding natural groups, which are reproductively isolated from other such groups.”
What is speciation?
Not the process of natural/genetic. Underlying biogeographic processes of isolating barriers, preventing gene flow.
What is genetic drift?
Rapid gene flow, certain characteristics dominate, movement of subset genes, thus removing older traits.
What is allopatric speciation?
Also called geographic speciation, occurs when populations become isolated which disrupts gene flow (Cabej, Epigenetic Principles of Evolution - 2012.)
Allopatrically formed species are post zygotically isolated - even when they can interbreed they are incapable of producing a fertile, hybrid offspring.
