There are approximately 12 transisthmian shrimps species, called sister species because they cannot interbreed effectively, in the Isthmus of Panama. It is believed that the closure of the Panama resulted to allopatric speciation of the shrimp population within the region.
Answer:
Letter a) Protists would have less permeable membranes than those in hypotonic or Isotonic environments, wlowing less water to enter the coll. Also, they could possibly develop higher salt concentration within the cell to retain water.