Exam 16: Mechanisms of Speciation

Each of the species concepts (morphospecies,biological,and phylogenetic)have strengths and weaknesses.Compare and contrast all three,and evaluate them for their relative usefulness.

Your textbook authors make the claim that "sympatric species with matching chromosome numbers are rare." Why is this?

Organisms such as prokaryotes (bacteria and archaea)―along with some eukaryotes―reproduce asexually.In the case of bacteria and archaea in particular,which exchange DNA but do not reproduce utilizing conventional sexual reproduction,the BEST way in which to define species is with ________.

Groups of organisms that cannot be distinguished morphologically but have no gene flow between them,and are indeed evolutionary independent units,are known as ________ species.

Early classification systems from Aristotle to Linneaus would have been most like what we now call ________.

Which of the following models of speciation hinges on a physical barrier which prevents gene flow between populations?

Hybridization between populations upon secondary contact may result in ________.

Isolating mechanisms leading to speciation have been documented by ________.