Examlex

Solved

Use the Following Description to Answer the Question(s) Below

question 30

Multiple Choice

Use the following description to answer the question(s) below.
The Isthmus of Panama (a narrow strip of land connecting North and South America) started rising about 10 million years ago. The Pacific and Caribbean oceans were completely separated by the isthmus about 3 million years ago.
Researchers have examined species of snapping shrimp on both sides of the isthmus. Based on the morphological species concept, there appear 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 seldom courted each other, and those that did mate seldom produced fertile offspring. (N. Knowlton, L. A. Weigt, L. A. Solorzano, D. K. Mills, and E. Bermingham. 1993. Divergence in proteins, mitochondrial DNA, and reproductive incompatibility across the Isthmus of Panama. Science 260:1629-32.)
-If the isthmus formed gradually rather than suddenly, what pattern of genetic divergence would you expect to find in these species pairs?


Definitions:

Attachment Preview

A feature in email or messaging applications allowing users to view the contents of attached files without needing to open or download them first.

Destination Folder

The folder to which files or data are being moved or copied in computer filesystems.

Organize

The act of arranging or structuring elements in a systematic way, making it easier to manage, access, or understand.

Outlook Items

Objects within the Microsoft Outlook application, such as emails, calendar events, contacts, tasks, and notes.

Related Questions