Sea turtles are known for their homing migrations from oceans thousands of miles afar to the beach where they were born to reproduce. This mysterious process is called natal homing, in which sea turtles have to travel through diverse habitats across the vast expanses of waters. This poses immense challenges, requiring very meticulous sensory capabilities for navigation.
To explain this distinct ability, scientists have put forward a hypothesis that sea turtles imprint on the magnetic field of their birthplace. Imprinting is a special form of learning with tremendously long-lasting effects that cannot be modified easily. Sea turtles have the ability to detect the magnetic field of the earth. When they leave the beach as hatchlings, they imprint the magnetic signature of the area and use it as a directional cue for their migratory return when they are fully grown.
A study has found that this natal homing behaviour has a distinctive advantage. In fact, turtles from a particular island have some unique immune genes in common. These genes are passed onto their offspring, endowing them with the ability to fight off local parasites and diseases that are prevalent in that particular island.
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