Evolution is the basis of all biology. DNA and the changes it goes through as organisms reproduce and face various pressures in the environment are responsible for taking life from a single-celled organism 3.5 billion years ago to the incredible biodiversity we see today.
There are still some who not only don't understand evolution but actively fight against the idea being taught. Misconceptions that can easily be explained are masqueraded as controversies, which does nothing but confuse others.
Time for a Reality Check of 4 common myths about evolution:
Myth 1: Nobody has ever seen evolution happen.
The most important thing to remember is that individuals don't evolve, populations do. Over time, genetic mutations and levels of certain gene variations change within a population.
Because microbes like bacteria and viruses are able to reproduce very quickly (sometimes a few times per hour), it's easy for scientists to see how they change over many generations. Strains of the flu virus evolve so quickly, we need to create a new flu shot each year to keep up with the changes. Evolution is also the reason bacteria are becoming resistant to antibiotics; a growing medical concern.
So why haven't humans "seen" massive speciation events, of one species turn into something else completely? Simply put, our lives aren't long enough to see it and it isn't a clear cutoff. The average person lives 70-80 years and it can take millions of years of small genetic changes to look back and identify that something is no longer like its ancestors.
Myth 2: If humans came from apes, apes should no longer exist.
We didn't just come from apes; we are apes. Many people forget this because humans are in a league of their own when it comes to intelligence and ability to use tools, but it's true. Ours is the last surviving human species, and for the last 10,000-20,000 years, chimpanzees have been our closest living cousin.
The last common ancestor between humans and chimpanzees was a primate who lived in the African trees about 6-7 million years ago. The population of that species fractured, with one staying in the trees, while the other went to the grasslands.
The group that went into the grasslands were subjected to many environmental pressures they needed to adapt to. Because it uses less energy to run on two legs instead of four, evolution favored those who could walk upright. Because the type of food available was different, the shape of the teeth and the digestive systems were also pressured to change in response.
That doesn't mean those who stayed didn't also adapt and change over time. While modern species may still prefer living in trees and getting around using four limbs, the chimps and gibbons we see today are very different from our common ancestor.
Myth 3: We're missing too many fossils for evolution to be true.
Scientists have found countless fossils ranging back billions of years, and this relative abundance makes gaps in the fossil record seem like much bigger red flags than they actually are. In reality, it's incredibly hard to make a fossil and the odds of it happening are pretty low.
For an animal or plant to become a fossil, they must first ensure that they're dying in the right place. For bony animals, they'd want to shoot for nice, soft sediment which would provide the minerals necessary to turn bones into fossils over the course of thousands of years. Getting encased by ice is also a good choice, as it would protect the body and allow for mummification to happen. They also need to hope that their remains aren't eaten or heavily trampled, otherwise they can kiss their chances of being recognized by future paleontologists goodbye.
There are some species that we will never know about simply because they weren't fortunate enough to die correctly in order to be fossilized. Because fossilization is so difficult, it's pretty astounding we've been able to find and understand as much as we have. When gaps in the record do occur, the rational choice is to acknowledge that fossils are tricky to make, not to discount all of evolution entirely.
Myth 4: Evolution can't account for morality.
Those who believe life was created by a higher power insist that if evolution is true, there's no reason for anyone to have morals and not just steal and kill indiscriminately.
Humans are social animals and our complex societies demand that we play well with others. If we take what isn't ours, exploit the efforts of others, or harm others for no reason, we can't develop the level of trust that we need to in order for things to run smoothly.
Sure, there are plenty of people who commit crimes and do the wrong thing. That's why we developed laws and courts in order to make sure that there was a way of punishing those misdeeds, but other social species like elephants and gorillas do the same thing and will punish or drive out those who don't play by the rules.
We're not moral because we're trying to score brownie points for the afterlife; we're moral because our species depends on it.
The final word:
Evolution is a complex phenomenon, and it's understandable that some people find it confusing, particularly if they haven't spent much time learning about it. The solution, then, is more education — not less.
Certain school districts either skip teaching evolution altogether or frame the lessons in a way that makes it seem like evolution is a dangerous idea and one that shouldn't be accepted, with some even putting warning labels on biology textbooks. This nonsense robs students of their right to a proper education and should not be allowed to continue.
As the Orthodox Chrisitan Theodosius Dobzhansky once wrote, "Nothing in biology makes sense except in the light of evolution."
Check back with A Plus every Monday for a new topic of Reality Check!
Cover image: Shutterstock