GENETICS OF SPECIATION

GENETICS OF SPECIATION - identify important features that...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
GENETICS OF SPECIATION Speciation has occurred, is occurring and will occur. These are undeniable facts. The problem is: How do we study speciation? There is no single approach since there is no single mechanism by which species speciate. Some approaches used in the past: Study patterns of morphological change in the fossil record in a well defined lineage of organisms. Success depends on many unknowns: stratigraphic resolution (will you "see" the speciation event); distinguishing geographic variants from true species (all you have is morphology. Comparisons of closely related species . These have speciated recently (assuming closely related ~ short time since speciation) so careful studies of their biology may
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: identify important features that contribute to reproductive isolation. Study intraspecific variation . Look for evidence of incipient barriers to gene exchange. Perform crosses between individuals from different regions; look for differences in genital morphology, secondary sexual characteristics. These may show some bimodal distribution suggestive of early steps in evolution. Must ask: what might we expect to find? This depends entirely on the model of speciation that might apply to the organism under study. Looking within a large species range for signs of variation may be fruitless if the speciation mode is peripatric with genetic revolutions?...
View Full Document

Ask a homework question - tutors are online