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Living fossil, important stage in the evolution of tetrapods.
The animation demonstrates the most important types of feathers and their fine structure.
Several analogous types of eyes have developed independently through convergent evolution.
A species of mollusk widespread in freshwaters.
Bats use ultrasound to navigate and hunt for prey.
Gradual metamorphosis, incomplete and complete metamorposis are common among insects.
A type of prehistoric reptile having bony plates on its back, which aided thermoregulation.
The poisonous bite of the Chilean recluse spider poses a serious threat to human health.