BIOB51H3 Lecture Notes - Lecture 19: Operational Sex Ratio, Goby, Howea Forsteriana
Document Summary
A population in which males and females cooperate in the care of young is most likely to have a(n: male-biased operational sex ratio, female-biased operational sex ratio, unbiased operational sex ratio, cooperation cannot affect the operational sex ratio. Species are smallest independently evolving unit: species follow independent evolutionary trajectories, defining species is contentious, currently over 22 different species. Past : no ability to assess ability to hybridize, determinations based on changes in morphological features. Present day : we have more than morphology to work with (behaviour, geographical distributions, dispersal tendencies, both a luxury and a curse, the lines are less distinct, overlaps are abundant. Important: not an issue for the organisms but it messes with the human desire to compartmentalize: we aren"t good with blurred lines! Phylogenetic species concept (psc): smallest possible group descending from a common ancestor; recognizable by unique, derived traits: useful for systematics, focuses on phylogenetic history.
