All animals adapt to their environment and evolve certain traits that help them survive. Some animals evolve in similar ways, even though they are very different animals. They end up developing the same solution to a specific problem in their respective habitats. This happens without them sharing a common ancestor.1
This is called convergent evolution.2
These adaptations are called analogous structures, while adaptations that come from a common ancestor between animals are called homologous structures. A perfect example to look at is butterflies, moths, and bats. They are all very different animals, but they developed similar adaptations, like how they fly and the mouthparts they use for pollinating.3
Another example is between insects, birds, and bats – all of them developed flight separately from each other, even though the characteristic is used for the same purpose.2 Going further than that, we humans and octopuses have similar adaptations in our eyes, including an iris, lens, and retina.1
Learn more about the wildlife around you with our DVD collection! Learn about birds with Nature: Eagle or Eyewitness: Bird, meanwhile check out more about wolves and how they fit into our world with The Great Wolf Divide, The Great Predator Debate, or Gray Area: Wolves of the Southwest.