Evolutionary Ecology

An interdisciplinary field incorperating ecology and evolutionary biology

Study how interactions of species within biotic and abiotic envrionment is shaped by evolutionary histories

Understand how ecology influences evolutions of new species

Speciation - formation of one or more species from ancesteral species

Occurs when populations of ancestral species are reproductively isolated

Types:

• Allopatric - two+ populations geographically isolated (common)
• Peripatric - small groups break off from geographic range of species
• Parapatric - populations not geographically separated by colonisation of new habitat/niche causes division
• Sympatric - no geographic or habitat barrier
• Cryptic - results in individuals morphologically identical but different species

Sister species - two species most closely related to each other

Represent evolutionary relationships using phylogenetic trees, built on morphological characters, genetic characters or both. Extinct species added using morphological characters

Synapomorphies - characters shared between most recent common ancestor and all descendants

Clade - group of organisms with all descendents of most recent common ancestor

Study of historical processes influencing modern species distribution using molecular tools. Helps understand genetic population divergence and speciation processes

Phylogeographic break - location where two or more clades come into contact

Example - Mexacanthina lugbris

Sea snail can be split into 2 genetically distant clades - diverged ~500tya when Pleistocene seaway along California peninsula was thought to be present. The seaway closed ~400tya - not enough time for new species to form. Resulted in different morphology (shells) and genetics. Further differences seen in terrestrial and marine species e.g. lizards, shrimps