Hello everyone and welcome back to my blog The Fire where I talk about biology and issues relating to that, personal development, and combine other branches of science such as physics, geology, and chemistry to give deeper insights into how life is experienced.
Today I’ve decided to talk about how the earth and living things change over vast periods of time. It’s important to emphasize the amount of time that passes and how drastically flora and fauna can change from hundreds to thousands to millions of years.
From what I gather from my experience interacting with Philadelphia’s educated and scientifically literate population most people understand that evolution is a fact and how it occurs over deep time. I have to admit though, I didn’t quite understand it as well as I probably should have when I took those two biological anthropology courses in college. I knew and trusted the lineage of hominids that I descended from based on the fact it was in a textbook and it was about science. I could name you a couple of the different species that predated our own right off the top of my head: Australopithecus Ramidus, Homo Ergaster, and, of course, Homo Naledi, but I didn’t truly understand just how evolution worked. This is for two reasons. One was that I didn’t quite care about understanding evolution fully, instead I just wanted to make sure I did well in my class. The second reason was that I was, to a pretty sizable extent, scientifically illiterate. In college I often felt like I had to work harder than most people just to keep up because I wasn’t used to or knowledgable of so many things I learned, but this is a topic for a later time. Right now I am knowledgable and persistent enough to know things I did not and as someone who is dedicated to science I feel it is my responsibility to educate. So that’s what I’ll do.
Going Through Changes
Anyway, let’s look at photo. A photo of an ape. An ape you won’t see roaming the streets of Philadelphia today. It was bipedal, it had white’s in it’s eyes, it buried it’s dead, wore clothes, and made fire. The ape I refer to is known as Homo Neanderthalensis, or AKA Neanderthals. They are our closest related human relative often used in adjectival form when referring to someone is who is barbaric and classless. Notice each and every single similarity.
For this next photo we see a less familiar face. One with a considerable amount of facial prognathism (extended chin and mouth region) and much shorter than we are today. This is Homo Habilis, the first of the genus Homo. Notice the subtle yet extensive differences in between these two creatures. Habilis’ held it down for a much longer amount of time with a smaller brain than his little bro the Neanderthal.
Next we look at the Australopithecines. Again, compare phenotypical features you see. One of the most well known Australopithecines is Australopithecus Afarensis. He was also bipedal, but adapted for boreal lifestyles.
And the list goes on and on and on. All the way back to the first ape. To the first prosimian. And the first mammal. And the first reptile. And the first amphibian. And the first fish. And the first bacterias and archaeas. We are all a product of BILLIONS of years of evolution…..fascinating isn’t it?!
*Think of these three different animals and then think of contemporary Australian Aborigines. What similarities do you find?
Teenaged Mutant Gene Mutations
So how exactly does this process called evolution work? I’m glad you asked my handsome friend. When your parents had you their genes mixed together to make you, and some random genetic mutations occurred. Which also occurred in your parents when your grandparents had them. And so on and so forth. Over time these tiny genetic mutations build on each other, except you can’t notice it by observing our own species because of our relatively long lifespans compared to bacteria. Bacterial genetic mutations are much quicker and evolution is much more rapid.
In Bill Nye’s new book Undeniable he likens the process of evolution to transforming a wagon or cart into a bicycle. If at any moment during the transformation process the cart is not capable of being steered or driven in any way you would have to abandon it and it would die. During the changes it undergoes it has to still be able to be workable and survive.
He also mentioned how giraffe’s have seven vertebrae in their necks like we do. That should show you evidence of common ancestry and gene mutations in their grandest form.
Comprehending Deep Time
Neil Degrasse Tyson said it best one day on a podcast with Larry King that’s also a 45 minute YouTube video. Larry questioned how Neil is sure he knows that certain things have occurred in space. Then Neil explained and one particular part of what he said stood out to me and I’ll never forget it. He told Larry “that’s because you only live for about 80 years, and not billions.” Which is so accurate because imagine what you would witness if you lived for thousands, millions, or billions of years. You would see things and have the answers that so many scientists don’t have or might never have in unlocking certain mysteries.
If you lived long enough you would see places that were once filled with water become canyons. You would see a cleaner, clearer sky with much more oxygen and countless other mind-blowing differences. But that’s ok. It’s not your fault you don’t believe in or accept things about the earth that are derived from scientific study. It’s very understandable. But you should at least try to. There’s a lot places on earth you can travel to and see first hand the result of natural phenomena over deep time. Buzzfeed actually just tweeted a list of places you probably haven’t heard of which clearly show how the physical impacts of geologic and meteorological processes over long periods of time.
As far as living things go they live, grow, and die and change over time because of gene mutation. Which is why biodiversity exists. Back in Charles Darwin’s HMS Beagle days he didn’t know about molecular biology the way we do and he doubted enough time had passed on earth for there to have been as much biodiversity that he theorized. Although, thanks to James Hutton and Charles Lyell, he integrated uniformitarianism into his study. In the earth’s 4.5 billion year history there has been more than enough time for life to evolve. With several mass extinctions, intelligent dinosaurs, and shifting landmasses life has had every chance to respectively exist and die off.
So just as in your daily life always remember that change happens gradually. Not overnight.
Smithsonian National Museum of Natural History website