[Campbell Biology P.935] Which of the following animals primarily utilizes a countercurrent ... | Practice Question

Which of the following animals primarily utilizes a countercurrent heat exchange system to conserve body heat in cold environments, as described in the provided text?

  • A: Iguana of the Galápagos Islands
  • B: Humans
  • C: Bottlenose dolphin
  • D: Pigeons

Explanation

The text explicitly states that bottlenose dolphins and Canada geese utilize countercurrent heat exchangers in their flippers and legs to reduce heat loss to cold water. Iguanas use vasoconstriction, and humans/pigeons use evaporative cooling mechanisms sweating/panting/pouch fluttering which are different strategies for temperature regulation, often for cooling rather than retaining heat in cold extremities.