Vestiges and Atavisms
When confronted with the evidence arising from vestiges, creationists wallow in their ignorance by saying “Vestigial organs aren’t really useless as the evolutionists say”, and then they carry on to show how our appendix is actually useful. Little do they realise that biologists do not claim that vestigial organs are useless. Simply, they are organs which are now serving a different purpose than what they had been originally evolved for. I will now present some examples.
Flightless Birds – Why would the Almighty God create birds which cannot fly? The Galapagos Flightless Cormorants still take care of their wings although they do not fly. The answer to this riddle in evolutionary terms is very simple. Once they were able to fly, until the need to fly lessened (less predators in Galapagos), that natural selection acted upon the inability to fly. Flying costs a lot of energy and it is therefore not efficient to keep their wings unless they really need to. The wings have not disappeared completely either because they have been put to new use (as with the ostriches) or we are simply witnessing a slow transition from wings to no wings.
Hindlimbs of Whales – Go to a museum now and look at the whale fossil. You will see tiny hindlimb and pelvic bones hanging separately from the rest of the skeleton. This is because the common ancestor of whales had hindlimbs. Now, whales don’t walk on land, but a remarkable trace of their evolutionary history can be found in their skeleton. Creationists argue that these vestigial bones aren’t actually useless, but that’s missing the point entirely.
Vestigial eyes – Some animals live in darkness, and we know that they descended from animals which once lived aboveground. Because they no longer need eyes (eyes are easily damaged and expensive to keep), natural selection favoured “no sight”. In the blind mole rat, the eye has been covered with a protective layer of skin. They have an eye, but they can no longer see anything. Blind mole rats evolved from rodents which once lived aboveground. Another example is the Mexican tetra (C. Astyanax mexicanus), a blind cave fish.
More examples – Dandelions: although they reproduce without fertilisation, still have flowers and produce pollens. Flightless beetles: still have perfectly formed wings, just hidden underneath covers. Pythons: still carry vestigial pelvises; it has been predicted by evolution that snakes descended from four-legged reptiles.
Human vestiges – The appendix: was important to our leaf-eating ancestors, now it does more harm than good, but medical advancements have reduced the mortality rate to 1%. The coccyx: is the remnant of tailbones from our primate ancestry – some people are born with tails (see atavisms). Arrector pili: are goosebumps; our ancestors raised their furs for insulation when it is cold. Ears: Some people can wiggle their ears – these muscles are the same as those in cats and other hunting animals; these animals needed to move their ears around to localise sounds.
Atavisms – are reappearances of certain characteristics, they occur in few rather than all organisms. Few examples: human with tails (known as coccygeal projection), horses with extra toes. Some genes are simply inactivated after birth – such as the baby’s lanugo hair, or the dolphin’s olfactory receptor genes, or the platypus’ (deactivated) stomach.
My dear creationists, proving that vestigial organs are useful does not disprove evolution, it only testifies your massive ignorance for science. Still, vestiges and atavisms are just the tip of the ice-berg of the evidence for evolution.