Reconstructing Phylogeny Flashcards
What is cladistics based on the analysis of?
Cladistics (tree construction) is based on the analysis of homologous, morphological and molecular species
What is plesiomorphy
An ancestral character state
What is symplesiomorphy
A character state shared by a number of groups but inherited from ancestors older than the last common ancestor
Define autapomorphy
A derived or specialised character state unique to one group
Define synapomorphy
Apomorphy shared by two or more groups which originated in their last common ancestor
This can be used to show that two species are evolutionarily related
What can effect the accuracy of cladistics
Hybridisation (interspecies crossing)
Different rates of evolution
Homoplasies
Define homoplasies
Similar characterises that evolved superstition either through parallel or convergent evolution
What is a distance character matrix
A matrix that records the number of differences between a pair of species
What is meant by maximum parsimony in terms of a phylogenetic tree
The tree with the least amount of changes. It is always the shortest possible tree.
