My aim in this essay is to clarify what evolution actually is and to debunk some common misconceptions about evolution. A lot of people get their information regarding evolution from unreliable sources or from people who don’t actually know the specifics. Sometimes folks get their information from people who are misinformed, or sometimes from people who intentionally disregard facts because of their religious ideologies for example. I suppose this should be the first place I start since the idea of evolution should in no way have any effect on someone’s religious beliefs.
Evolution makes no claims as to whether a person has a soul or not, or whether you’ll see your grandma in heaven after you die. Evolution is a natural process, and Science can be used as a tool to describe that process, comparable to Ohm’s law or E=mc². The Theory of Evolution describes a process in which all living species came to be in their current form. It’s the best theory we have to date, and no other competing theory comes close to better describing how life-forms have came to be. If there was ever any piece of evidence that can irrefutably disprove evolution, scientists around the world would immediately start to rethink their ideas and adapt to this new piece of information so they can continue to describe natural processes and laws. Evolution does NOT describe how life, or the universe for that matter, began. For the time being, that is left to theology, or other similar philosophies.
Atheism – and theism for that matter – has nothing to do with evolution… at least as much as they do with gravity. You don’t need to believe – or not believe – in a god to know that both gravity and evolution are facts. We know that gravity is real, the question is, ‘what is it?’ The theory of gravity tries to explain this. Ever since Newton, we’ve been trying to describe gravity and how it works, and we’ve come a long way however, gravity is ‘still a theory.’ The same is true with evolution. Basically every single rational scientist agrees that evolution is a fact, some of them however may disagree on the details. Simply because we don’t know every detail doesn’t make it any less real though. Just because I think the tread design on my tires is superior to yours doesn’t mean that the idea of the tire is worthless! Denying evolution is just as silly as denying gravity. There are many people on both sides of the religious fence who believe that evolution is real. In fact, the Catholic church for some time now has held an official stance on evolution that completely coincides with modern science. Pope John Paul II said evolution is “an essential subject which deeply interests the Church.” He recognized that science and Scripture sometimes have “apparent contradictions,” but said that when this is the case, a “solution” must be found because “truth cannot contradict truth.” John Paul accepts evolution “as an effectively proven fact.” Yes, those are his words. So whether or not you believe in god shouldn’t have any effect on your opinion of evolution.
So what is evolution? Evolution is the idea that life changes over time, sometimes resulting in speciation, and the idea that all life currently in existence today arose from a common ancestor. The evidence for this is overwhelming, resulting in a robust consensus of scientific opinion. Evolution takes place when a small random mutation occurs in an organism’s DNA resulting in a slightly different organism from parent to offspring. Mutation is then guided by Natural Selection: when given two variations (or mutations) of an organism, one will be more suited to a particular environment and will have more of a chance to pass on it’s genetic information (including that mutation). Survival of the fittest.
An extremely simplified example would be to imagine a species of horse-like creatures happily living on an island. Imagine these horses are herbivores eating only local types of trees. After a few thousand, or perhaps millions of years, this group of animals become divided by some type of geologic formation; maybe a mountain divided the island or the entire island split through plate tectonics. Now there are two separate groups of the same species. Remember, these two groups can no longer mate since they cannot climb mountains or swim… they are completely isolated. Due to climate change (since one side of the mountain enjoys a different, more rainy environment), the trees these horses love to eat grow substantially taller on that side of the mountain. Since the horses need to eat to survive, many of them perish due to lack of nutrition. Only some of the taller horses end up surviving because they are able to reach the leaves. They have a slightly different genetic makeup than the rest of the population; they have a mutation that makes them slightly taller (not every human is the same height right?). In time, the entire population becomes a tall version of the same species on the other side of the island, who by the way, are still living happily unchanged since their trees stayed the same height. Now, after a LONG time, and many mutations later driven by similar circumstances, when you put one horse of each of the separate group side-by-side, they look completely different! In fact, their genetics differ so much because of so many mutations, they can no longer interbreed! This, by definition, means that these two groups of horses, who started out as the same species, are now completely different species, thus illustrating evolution and speciation. Again, this is an oversimplification, but a correct example nonetheless. A book I would highly recommend for further reading is “The Blind Watchmaker” by Richard Dawkins.
So one question some people have is, ‘if we evolved from apes, why are there still apes around?’ This is a common misconception probably driven by the classic evolution picture depicting a monkey who slowly stands up to become an erect human – and is totally wrong. Evolution is a branching tree, not a ladder. We did not evolve from apes. We evolved WITH apes. We ARE apes, in the family Hominidae consisting of orangutans, gorillas, chimpanzees, and humans, collectively known as the great apes. Humans and chimpanzees share a common ancestor. Chimpanzees and gorillas are our cousins, not our ancestors. (For more information, check out ‘The Ancestor’s Tale’ by Richard Dawkins.) Between 5 and 7 million years ago, somewhere in Africa, there lived a species that later gave rise to both humans and chimpanzees. This animal was neither a human nor a chimpanzee, although it probably was more like a chimpanzee, if only because chimpanzees are more like the rest of the apes than humans are.
Did you know I was related to James Thurber? That’s right, the American author James Thurber. I’m also related to the American president George Bush if you go back far enough. In fact, if you trace my lineage farther still, I’m even related to a pirate, Jean Lafitte! And if you go back even further, I’m related to you! All humans share a common ancestor at some point in history. We all came from somewhere. All animals came from somewhere. The common ancestor we share with chimpanzees is our 250,000-greats-grandparent. It’s painfully clear in the fossil record, at least in the scientific community. I know there are a lot of individuals and groups who would say otherwise and try to convince others of the same, but they simply haven’t done their research. If you are unconvinced, please read “Evolution: What the Fossils Say and Why It Matters” by Donald Prothero. Read ANY modern scientific writings on fossils for that matter.
If the fossil record doesn’t convince you, isn’t it obvious in the genetic coding? You don’t need to be a geneticist to know that every living thing has DNA. DNA is what makes you who you are… and what you are. Humans share 98% of their DNA with chimpanzees, our closest relative. That is, 98% of your DNA exactly matches a chimpanzees. Not only that, humans share roughly 60% of our DNA with a fruit fly. We share 50% with bananas! Just the fact that every living thing HAS DNA should be a big enough clue that we all share a common ancestor.
Another misconception is that Humans are the pinnacle of evolution. Some people believe that Homo sapiens is the ‘latest and greatest’ evolution has to offer. However as we’ve discussed, evolution isn’t a linear progression, but a branching tree. Everything alive today has had the same amount of time to evolve as humans have. Furthermore, there are many things other species can do that humans simple cannot. We can’t detect tiny flying bugs with sonar as bats do. We do not have gills and therefore could never live underwater like fish can. Snakes can ‘see’ in the infrared, and I’ve never met a person who could do that, although I know a lot who would like to! Organisms evolve to adapt to their environment as best as they can. Humans have adapted to our environment exceedingly well which is why we’re still here, just like birds have evolved hollow bones to make them light- weight which make them more efficient to fly.
But nature looks so perfect in all its elegance! Nature looks as if everything is perfectly fit and wonderfully balanced that it must be designed! Oh, really? You mean how plants use the red and blue ends of the electromagnetic spectrum and reflect green light? Well, if plants were ‘perfectly designed,’ why wouldn’t plants be black and absorb ALL the light coming from the sun? Nature can be extremely wasteful. Can anyone please tell me the reason for a male nipple? What about the reason for vestigial organs such as the appendix, the tailbone, the tonsils, etc.? These are organs left over from evolution that no longer serve a purpose. In fact, humans are arguably the worst design possible for a bipedal animal you could think of. An ostrich is far more adapted for bipedalism than humans could ever dream of… and those are just human examples. What about certain snakes that still have remnants of hind limb and hip bones? The same goes with whales and other cetaceans. You can find small vestigial leg bones deeply buried within the back of their bodies. Why would a creator, in all his glory and perfection, create species with these unused, wasteful parts that serve no obvious purpose, or are just poorly designed in the first place? If things were truly designed, I have a feeling things would look a whole lot different around here.
If things are evolving, why are there creatures around today that lived millions of years ago? Why have alligators remained relatively unchanged since the time of the dinosaurs for example, yet the ancestors of other species like modern birds WERE the dinosaurs? Why haven’t alligators evolved too? The theory of evolution doesn’t say that species must evolve morphologically. In an unchanging environment, a species that is best suited for that environment has no pressure to change. Basically, if it works, why fix it? In addition, there are plenty of examples of so-called fossil species that have evolved significantly. Cockroaches, for example, include over 4000 species of various shapes and sizes. Not only that, organisms may evolve in perhaps not-so-obvious ways, like the horseshoe crab. Modern horseshoe crab ancestors more than likely had a significantly different immune system than they do today.
So if evolution is a fact, why aren’t things evolving today? Well, they are! Evolution involves very small changes over a long period of time guided by natural selection. Things evolve constantly, it’s just hard for humans to notice since evolution takes such a long time to have any dramatic effect or change, and human life-spans are so short, relatively speaking. There are plenty of examples of documented evolutionary changes and creatures in various stages of ‘completion.’ An example of animals in transitional stages are certain fish that can live out of water for extended periods of time, using their fins as legs, and can breath air. Ever heard of a mudskipper? If you live in the southern United States or southeast Asia, I’m sure you’ve heard of the walking catfish which is considered an evasive species and a pest because they can leave any pond or lake and invade any surrounding body of water with ease. What about aquatic snakes? Or how about various gliding animals for instance? The flying squirrel and similar animals may well be on their way to become more bat-like. These are a few examples of entire species evolving new traits that may someday become an entire different species. But we don’t have to look any further than inside ourselves to watch evolution happen even on a daily basis. Have you ever gotten the flu? Do you get a new flu shot every year? Ever wonder why you need to get a new flu shot annually? The reason is because influenza is a virus that is constantly mutating and evolving to adapt to new man-made vaccinations. Since viruses and bacteria have relatively short life-spans and genetic codes, it’s extremely easy to watch evolution in action.
What are the odds that we live in a universe that has the exact parameters needed for life to evolve? The theory of evolution makes no claims to explain the origins of life, or the universe as a whole, but I feel this is a question that is commonly asked and deserves an explanation. This is just the same as a hypothetical thinking puddle of water asking, “what are the chances that this pothole I live in matches my shape exactly!? Of all the different shapes and depths a pothole could be, I find it hard to believe that the one I happen to live in is the exact shape needed to fit me perfectly!” The obvious answer is that it isn’t a chance that the puddle of water matches the shape of the pothole, it’s that the puddle is the shape it is BECAUSE of the shape of the pothole. It couldn’t be any different! If any of the parameters of the current universe were slightly different, we wouldn’t be here today to even ask the question. We are here BECAUSE the parameters of the universe are what they are. Furthermore, who’s to say that other varying combinations of the laws of the universe couldn’t wield life completely unimaginable to us? There could be other universes with life-forms asking the same question as we speak! This is hardly a question for evolution to answer, and can easily be explained by some simple reasoning. So to get back to evolution…
I think the real champion of evolution is time. Lets talk about time for a minute. The age of the universe is about 13.75 billion years old. That, in itself, is an unimaginably long period of time. Unimaginable at least to humans. The Earth has been around for 4.6 billion years, and life, according to fossils and many other lines of evidence, started not long after at about 4.3 billion years ago. Funny how I refer to ‘not long’ as 300,000,000 years! That is a long time. The average human life-span is only about 30,000 days! Animals, as we know them, came on the scene around 600 million years ago. So if you think about it, 95% of life’s history was nothing more complex than single cells. Fish showed up 500 million years ago… insects, about 400 million years… mammals arrived about 200 million years ago. Now lets think back to the time of Jesus. He lived around 2,000 years ago. For some reason, when I think about the time of Jesus, I feel like that was an extremely long time ago. It’s hard for me to imagine just 2000 years ago. Doesn’t even seem real right? Well, it’s a blink of an eye since humans have even been around. Start counting to 2,000… and stop at 2. That’s the relationship between the age of Jesus and the beginning of human history.
Don’t think the Earth has been around long enough for evolution to occur? Here’s an example of how powerful time really is. How long do you think it would take to flatten a 1 mile high mountain simply through erosion? Just by some light rain through the years, you would think it would take a few billion years maybe? Perhaps longer? Lets do a back-of-an-envelope calculation: Lets assume (for easier calculations) that the mountain is a cube one mile high, and one mile on each side. That’s one cubic mile of mountain right? That’s a pretty big mountain, so let’s assume there are maybe 6 small streams that wind their way down the sides. Lets say that each stream carries with it 1 cubic yard of stuff (rocks and pebbles) per day. With 6 streams, that’s 6 cubic yards (1 yard = 3 feet, 1 cubic yard = 27 cubic feet, 6 cubic yards = 162 cubic feet) or 162 cubic feet gone per day. With a year being 365 days, that’s 59,130 cubic feet per year. A mile is 5,280 feet. A cubic mile equals about 147.2 billion cubic feet. 147.2 billion divided by 59,130 equals about 2.5 million years! Sure, 2.5 million years is a long time, but as we’ve seen, it isn’t THAT long in the grand scheme of things. That’s less than 0.06% of Earth’s history! Humans have been around almost as long! As noted before, there is evidence of life only 300,000 years after the formation of the Earth, giving evolution 4.3 billion years to obtain it’s current state. Time, indeed, is on evolution’s side.
I could go on and on about all the details of evolution and give mountains of evidence that evolution is real, but maybe the best way for someone to truly learn and understand it is to not take my word for it, but research it themselves. Instead, maybe what we should do now is embrace it. Evolution, as I have said, shouldn’t have any effect on someone’s faith whatsoever. It merely describes how one aspect of nature works. Some people may also say that when you break something apart to see how it works, you take some of the beauty away from it; you’re ‘unweaving the rainbow’ as many have said. You take the magic away from it. I have to wholeheartedly disagree. When you understand how something works, especially something as complex and intricately detailed as evolution, it only adds to the beauty of it! When you understand the concepts of evolution and how it works, it’s an amazingly simple and useful idea that can be applied to many aspects of our lives. Understanding how something works shouldn’t make it any less beautiful, it should make us appreciate it that much more! Every since I can remember, I’ve always wanted to know how things work. I’ve always enjoyed science and the careful approach it takes towards understanding and describing the things around us. As a matter of a fact, since I have learned how evolution,
biology, physics, nature in general works, I have become orders of magnitude more grateful that I am even here in the first place!
Let me explain: It is an incredible chance that I am here right now. It is an incredible chance that YOU are here right now! The odds that any one of us are here are so astronomically small that we should effectively not exist. Now don’t take this the wrong way. I don’t mean the chances are so small that the only way we could be here is if someone created us or magically put us here. What I mean is any one of us specifically shouldn’t exist. Take this example: What are the odds that you will win the lottery? Probably something like 1 in 14 million right? That’s more than likely not going to happen. But what are the odds that SOMEONE will win the lottery? Basically 100%! The point is, someone was going to be here. Someone was going to exist, it just happened to be me (or you)! The chances of the exact combination of genes to make me (or you) are so low that it will never happen again for the entire age of the universe. How lucky we are to be here right now! How lucky you are to even be reading this! We should rejoice in the fact that we are here and that we have got to spend the time we have together and enjoy it as much as we did. I know I have had an unbelievably wonderful time sharing my laughs, my tears, my joy and pain… my life, with everyone I know. I wouldn’t have been me without them. I want to thank them for sharing their precious life with me and at the same time, making me who I am, because they will never get those moments back. 30,000 days. About 80 summers worth. What did you do last summer? We only get one life. We should enjoy it and learn as much as we can while we’re here. In the words of Louis Armstrong, “what a wonderful world.”