I will finish material from monday (mass extinctions),

Biogeography

Continental Drift.

A brief history of plate movement (See text for figures)

the continental collision at the end of the Permian was thought to be involved in the extinction of marine families.

The grand scale -- Biogeographic realms

I - Palearctic

II - Ethiopian

III- Oriental

IV - Australian

V - Nearctic

VI - Neotropical

Example of Ratites -- Flightless birds

Emu, Ostrich, Rhea distributed Australia, Africa, South America

Example of Mammals

Placentials verus Marsupials


Levels of endemism is the key: the degree of restriction in a species geographic range.

Phylogeny -- Knowledge of taxonomic affinities is essential. You must be dealing with a monophyletic group.

The problem of Convergence -- There is a tendency to find animals among biogeographic realms to converge in morphology, life history, and ecology

For Monophyletic taxa two processes have been proposed to explain biogeographic patterns:

1) Dispersal from the region in which a clade originated

2) Vicariance -- a formerly disjunct distribution has become fragmented by some external factor.

Phylogenetic evidence used as indicators of biogeographic history (overhead)


Vicariance biogeography examples in operation

Cichlid fish in the African Rift Valleys (Axel Meyer)

Placentials and Marsupials


 

I will also begin a review by going over the population genetic aspects of a debate in conservation biology over the design of nature preserves - Single Large or Several Small Preserves or SLOSS for short.