CorrectQuestion: Which of the following physiological adaptations is most critical for deep-diving marine mammals like sperm whales during prolonged submersion?

Wed, 06 May 2026 17:13:45 +0000

# Why Caution is Key: The Most Critical Physiological Adaptation for Deep-Diving Marine Mammals Like Sperm Whales Deep-diving marine mammals such as sperm whales exhibit extraordinary physiological adaptations enabling them to endure prolonged submersion—often exceeding an hour—under extreme oceanic pressures. While numerous adaptations—including oxygen management, thermal regulation, and logistical metabolic adjustments—contribute to their diving prowess, the most critical is the ability to tolerate elevated carbon dioxide (CO₂) levels without triggering an urgent need to surface. ## The Critical Role of Increased CO₂ Tolerance Unlike humans, deep divers like sperm whales do not feel the rising urge to breathe when CO₂ builds up in the blood. This ability is a standout adaptation among marine mammals, allowing extended dives without frequent surfacing. As daily dives can last 20–90 minutes and depths often exceed 1,000 meters, managing CO₂ efficiently is vital. Accumulation of CO₂ would normally prompt an immediate surfacing response to avoid hypercapnia—a dangerous spike in blood CO₂ levels that risks unconsciousness or death.