Evolution is a group of scientific theories that, explained very simply, state that organisms change and adapt to fit their environment over many years of selective breeding. Those who are most likely to survive are the most likely to breed and thus the changes and mutations that are advantageous will become commonplace. Now evolution is a theory, and a theory doesn’t mean that something is an absolute certainty… what it means is that at the moment that theory is the one that best explains the evidence that has been discovered which is leading humans to ask questions. However there’s one very big piece of circumstantial evidence in favor for evolution; vestigial organs.
Everyone has, or had, vestigial organs at one point. These are body parts that, while extremely useful at one point in time, are no longer important. The body hasn’t managed to phase them out completely yet though, even though they’re not used anymore. One example is something that most teenagers dread; human wisdom teeth. These wisdom teeth are pretty likely to come in impacted, or to cause problems. Extracting them is often necessary, and it does no harm to the owner of the teeth. The same is true of the human appendix, which doesn’t really do much for us unless it swells up and poisons our insides. Why do we have these? Well, wisdom teeth seem to come from a time when human mouths were much bigger, and we had larger jaws that would support additional teeth. The appendix is still used by a number of animals, and these animals use it to digest plant matter… so it would stand to reason that when people ate a diet that was higher in cellulose and not so filled with McDonald’s that the appendix was used to help us actually digest all of the raw salad we were taking in.
Of course humans aren’t the only ones to have vestigial organs. Whales have tiny (comparatively speaking) leg bones that are used for… well nothing anymore because they live in the ocean and have tails. Emu and other flightless birds like penguins still have wings that have either adapted to other purposes or which do precisely squat. Even dandelions still have vestigial sex organs from time immemorial that do little other than add a confusing addition to the plant’s anatomy. When viewed this way, evolution is a very sound theory because it explains all of these things. If people, animals and really the whole world exists in a fluid constant of change where nothing is the way it may once have been through a combination of genetic and environmental factors then it explains a great deal about the world we live in. Whether you agree with evolution or not, it’s just a theory. So until we find something with more evidence, circumstantial or otherwise, then this is the best guess we have to go on.
“The 5 Strangest Things Evolution Left in Your Body,” by Colin Murdock at Cracked
“Top 10 Useless Limbs and Other Vestigial Organs,” by Anonymous at Live Science