Use the Following Information to Answer the Question

question 63

Multiple Choice

Use the following information to answer the question.
About 3 million years ago, the Isthmus of Panama (a narrow strip of land connecting North and South America) formed, dividing marine organisms into Pacific and Caribbean populations. Researchers have examined species of snapping shrimp on both sides of the isthmus. Based on the morphological species concept, there appeared to be seven pairs of species, with one species of each pair in the Pacific and the other in the Caribbean. The different species pairs live at somewhat different depths in the ocean. Using mitochondrial DNA sequences, the researchers estimated phylogenies and found that each of these species pairs, separated by the isthmus, were indeed each other's closest relatives. The researchers investigated mating in the lab and found that many species pairs were not very interested in courting with each other, and any that did mate almost never produced fertile offspring. (Reference: Y. Kondo and A. Kashiwagi. 2004. Experimentally induced autotetraploidy and allotetraploidy in two Japanese pond frogs. Journal of Herpetology 38(3) :381-92.)
If the isthmus formed gradually rather than suddenly, what pattern of genetic divergence would you expect to find in these species pairs?

• A) similar percentages of difference in DNA sequence between all pairs of sister species
• B) greater percentage of difference in DNA sequence between species that inhabit deep water than between species that inhabit shallow water
• C) greater percentage of difference in DNA sequence between species that inhabit shallow water than between species that inhabit deep water
• D) smaller percentage of difference DNA sequence between species that inhabit than between shallow water

Evaluate financial performance metrics including net operating income and average operating assets.

Understand the impact of new investment opportunities on existing financial metrics.

Calculate sales and net operating income for different fiscal periods.

Analyze financial improvement or degradation over fiscal years.

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Definitions:

Rod Vision

Rod vision refers to the aspect of vision that allows living organisms to see in low light conditions, enabled by rod cells in the retina that are more light-sensitive than cone cells.

Brightness Contrast

The difference in light intensity which makes an object distinguishable from others or from its background.

Mach Bands

An optical illusion in which the contrast between edges where two different shades meet appears exaggerated.

Brightness Contrast

The difference in brightness between objects or parts of objects, which influences the perception of their visual appearance.