In the Oceans on Either Side of the Isthmus of Panama

question 6

Multiple Choice

In the oceans on either side of the Isthmus of Panama are 30 species of snapping shrimp; some are shallow-water species, others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago. The oceans were completely separated by the isthmus about 3 million years ago.
In the figure, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B) . The seawater on either side of the isthmus is separated into five depth habitats (1-5) , with 1 being the shallowest.

-The Panama Canal was completed in 1914, and its depth is about 15 metres. After 1914, snapping shrimp species from which habitats should be most likely to form hybrids as the result of the canal?
The Panama Canal was completed in 1914, and its depth is about 15 metres. After 1914, snapping shrimp species from which habitats should be most likely to form hybrids as the result of the canal?

• A) A5 and B5
• B) A3 and B3
• C) A1 and B1
• D) A1-A3 and B1-B3 have equal likelihoods of harbouring snapping shrimp species that can

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