creation
Sea Turtle Osmoregulation
Specialized glands that allow turtles to drink seawater.
The Evidence
Sea turtles live in saltwater but require fresh water to survive. They possess specialized 'salt glands' behind their eyes that filter excess salt from their blood, which they excrete as thick, salty 'tears.' This allows them to drink seawater without dehydrating.
Historical Context
For a land-dwelling ancestor to evolve into a sea turtle, it would need to develop this complex filtration system *before* or *simultaneously* with its move to the ocean. Without it, the animal would die of dehydration. The gland had to be fully functional instantly upon entering the marine environment. This suggests a forethought in design to equip the creature for its specific environment.