Male mallard ducks have had emerald green head feathers and wings with metallic blue patches for hundreds of years,

whereas females have been drab, brown-feathered ducks. This phenotypic situation suggests that mallards may be an
example of ____.
a. directional selection
b. Polyploidy
c. allopatric speciation
d. disruptive selection
e. sexual selection


ANSWER: e

Biology & Microbiology

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A scientist discovers a new species near coral reefs in Australia. On basic microscopic examination and after conducting a few simple experiments, he finds that this single-celled species is photosynthetic (using sunlight for energy),

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Which term refers to the microscope's ability to show two separate objects as discrete and distinct?

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Biogeography is the study of

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The organism responsible for the majority of neonatal meningitis is ________.

A. Neisseria meningitidis B. Escherichia coli K1 C. Listeria monocytogenes D. Haemophilus influenzae E. Streptococcus agalactiae

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