Let’s take a look at sea turtles and attempt to figure out what morphological (physical) characteristics help them survive in the ocean.
All sea turtles are reptiles, which means that they breathe air, have scaly skin and are ectothermic (their body temperature depends on the surrounding temperature). Sea turtles are streamlined for ease of movement in water, with large flippers that propel them through the ocean and hard, bony shells that protect them from predators.
Sea turtles spend most of their lives in the sea, but begin their lives on land. During nesting season, which is typically the warmest months of the year, mothers leave the sea to lay their eggs on sandy beaches. Though they move easily through water, sea turtles are slow and jerky when they crawl up the beach. It takes sea turtle eggs about 50 days to mature and become hatchlings (baby turtles) that emerge from beneath the sand at night. Using the light of the moon on the water to guide them, hatchlings locate the ocean and begin their aquatic journey.
Hatchlings swim non-stop for days until they reach the deep ocean. They seek refuge on seaweed mats, where they eat small crustaceans and algae until they are large enough to forage without protection. Juvenile sea turtles will live like this for about 20 years, at which point they follow their instincts back to the very same beach where they were born to mate and make their own nests!
