Prehistoric Crocodile Relatives' Sinuses Hindered Deep Diving Evolution

Overview

• Thalattosuchians, ancient relatives of modern crocodiles, had large snout sinuses that restricted their ability to dive deeply.
• Unlike cetaceans, whose sinus adaptations allowed for deep diving by reducing pressure, thalattosuchians' sinuses expanded, preventing such evolution.
• The study utilized computed tomography to compare the skulls of thalattosuchians with modern crocodiles and cetaceans.
• Researchers suggest the expansive sinuses may have aided in salt excretion, a necessity for marine reptiles lacking efficient kidneys like those of cetaceans.
• Thalattosuchians became extinct in the Early Cretaceous, leaving their potential for further aquatic adaptation speculative.