Lecture 6 Flashcards
Biological Species Concept
‘Actually or potentially interbreeding natural populations, reproductively isolated from other such groups’
Phylogenic Species Concept
‘The smallest diagnosable cluster of individual organisms within which there is a parental pattern of ancestry decent’
Phylogenic Species Concept pt 2
This concept does not recognise subspecies. So once it was applied to primates species that were seen as subspecies were raised to species level. So the number of recognised species greatly increased.
Reproductive Isolation
Passively a by-product of other selection suck as drift. Actively selection for a specific mechanism, mate choice and disruptive selection.
Definition of species
Not as neatly packaged as one would think. By the biological species concept - ‘groups of
interbreeding natural populations that are reproductively isolated from other such groups’
Allopatric
This specialisation occurs when a barrier is formed which then what was once one species becomes two distinct species that are reproductively independent.
Peripatric
New species are formed isolated, smaller peripheral populations that are prevented from exchanging genes with the main population.
Parapatric
Partial geographic seperation of diverging population zones, species may interact but not enough to interbreed.
Sympatric
Forming two or more decendant species from a single ancestral species all occupying the same geographic location.
Punctuated Equilibrium
Species arise by splitting, no intermediated and speciation occurs quickly 5,000-50,000 years.
Taxonomy
Science of describing and classifying taxa
Systematics
Study of the evolutionary relationships among taxa.
Process: Choose taxa, choose characteristics, analyse and reconstruct tree, translated into classification and test hypotheses
