There is a lot of confusion amongst a lot of people about what these terms actually mean so I’m going to present my interpretations of each term and why I’ve chosen those terms, I’m also going to use this as an opportunity to explain the various principles in evolutionary theory. Experts, remember, this is the basics, so if you see something you disagree with, first think “Is what I’ve said a good enough simplification for someone who doesn’t know so much as you?” then comment based on what you’ve thought, because, hey, I’m human, it’s possible (Probable or even likely, I would say) that I will make some errors.
So, without further ado, I will start with possibly the most contentious: Darwinism. Darwinism is often used as a synonym for the “theory of evolution by means of natural selection” which while being quite a mouthful, is often what is meant by “evolutionary theory” today which I would argue is much more accurate than Darwinism. Why do I think “Darwinism” is a bad synonym for “evolutionary theory”? Because Darwin wasn’t our prophet, he wasn’t infallible nor omniscient. He didn’t discover everything through revelation, he discovered it through ‘plain old boring’ thinking about it.
As evidence for this, I present “Things Darwin Didn’t Know About”:
- Genetics: Gregor Mendel was a contemporary of Darwin, that is, he lived at the same time as Darwin and published his work in 1866 a full 16 years before Darwin finally kicked the bucket, however, Darwin never read his work. No-one even discovered the connection between Mendel and Darwin until the early 20th century.
- The Age of the Earth: Dating the Earth to millions of years was typical for theorists in Darwin’s time, however, with the discovery of radiometric dating in 1905 by Ernest Rutherford expanded the age into billions of years before eventually giving us the current age of 4.54 ± 0.05 billion years.
- The structure of the ‘tree of life’: Darwin didn’t know much about the relationships between species and groups of species. Indeed, in one of his earlier editions of “On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life” (Wonderful title) he hypothesised that a bear which swam through the water catching insects would be through natural selection transformed into a whale.
These principles, central to modern evolutionary theory, were at least in their infancy, and at worst, were completely misunderstood in Darwin’s time. Darwinism should effectively mean the original ideas theorised by Darwin and so does not represent current understanding in evolutionary theory.
Why is this important? Because it shows we’ve advanced since Darwin, that Darwin’s ideas weren’t accepted as dogma and then any dissenters were quickly ostracised by the scientific community. Evolutionary theory has been debated ever since the first ideas were put forward (There were several ideas concurrent to and even proceeding Darwin that suggested a mechanism for how diversity was generated in life, see Alfred Russel Wallace for an epic beard and a forgotten hero, also Lamarck who’s greatest contributions to science were not his blunders, see references below).
The problem for science in these debates was never about whether evolution occurred (See below for definition of evolution) but rather how it occurred. What effect does natural selection have? How much does genetic drift effect genetics of species? How fast does speciation occur? How important is extinction for the creation of new niches? Notice how none of these questions target the age of the earth, the permanence of species nor the fossil record? Creationists take note.
So, Darwin wasn’t perfect and therefore it’s important to separate out his ideas, the ones which began our modern evolutionary study from those that make up our current view. This also helps us to discuss controversy within science and the difference between debating an issue (Such as the effect of natural selection in evolution) and debating the fact of an issue (Whether evolution occurs).
Now, what is evolution then? If evolution isn’t Darwinism then what is evolution? Well what it isn’t is the theory of evolution nor evolutionary theory. Evolution on it’s own is the fact of evolution which is evidenced in the existence of fossils which are dated using radio-metric methods of all different sorts which are used depending on the condition of the rock. The fact of evolution is also evidenced by the studies of Grant and Grant on the Galapagos Finches, or the enormous amounts of studies done on fruit flies. Evolution, put simply, is the observed change in life as time has passed. The oldest rocks contain different animals and plants than younger rocks which are different again to modern flora and fauna.
But of course, if evolution is that, then what is the theory of evolution? Well to begin, you’d need to know the differences between theories, hypotheses, ideas, laws of nature, facts, et.c. but suffice to say that a theory is a body of tested ideas which explain facts. The theory of evolution explains how life has changed since it first emerged. It does not seek to explain the origin of life, the origin of the solar system, it is not the big bang theory, nor does it seek to disprove any god (Uncapitalised to point out all the gods that people think that word means.).
The theory of evolution is really the collection of tools we use to explain and demonstrate the way that life changes and has changed. The main tool that everyone knows about is of course, natural selection. To demonstrate natural selection, think about this:
A female weevil lays 300 eggs which mature in a month, roughly half of those weevils will be female, so 150 females in the next generation, each lays 300 eggs, that’s then 450000 weevils in two months, multiply that out after one year and there are nearly 260 septillion (260 followed by 24 zeros) weevils. If the weevils weigh 1g each, then the total mass of all the weevils would be equal to nearly half the mass of the earth (Earth mass = 5.97e24kg). Clearly, since we aren’t swimming in a sea of weevils, something is limiting them, preventing them from reaching this enormous mass.
Now, evolutionary theory, isn’t about what is limiting the weevils, but rather how the weevils are limited. The idea being that the limits on the weevils are selective, that is, weevils the best at being weevil-y will be better at resisting the factors which limit them. So, for example, the weevils I’m talking about are rice weevils (Sitophilus oryzae) and they live in enormous grain stores where there is a bit of an issue about how much oxygen they acquire, so, if a weevil is pretty good at living without much oxygen, they’ll do better in that environment.
However, this problem happens across the generations, it’s not just a problem for the current weevils, but also their descendants. So any benefit will only help the weevils as a whole survive if any resistance to low oxygen levels is heritable. If a weevil passes on it’s ability to use less oxygen then it’s descendants will be better equipped to survive than others.
This is just one mode for variation in a population to facilitate change (read: evolution). Hopefully you can see why this is such a big deal, to limit organisms in their way of life is the ground state for nature, things aren’t limitless and so animals will not all survive. This means that organisms will compete with each other for their ‘place’ in the population and their opportunity to reproduce. Then if the differences between the organisms can be passed on, then the populations will change over time.
This is all the basics of evolutionary change. This is what we use to understand biology today. Shocking it could be so simple. This post is getting pretty long now so I’ll cover other things in another post at some point. Things like sexual selection, the role of genes etc will be covered next time (If I ever do get around to carrying on this mini-series).
Lamarck: See Eight Little Piggies by Stephen J. Gould. In one essay (I forget which and don’t have my copy to hand) he discusses the misrepresentation of Lamarck. Though I know in the book he also discusses Goethe, Haley and Ussher as representatives of people who have been misrepresented by history.
Ideas: This essay is based heavily on my thoughts prompted by reading Scientists Confront Creationism: Intelligent Design and Beyond. Defining terms used in evolution is a topic discussed in a section of the book and it helped me to realise the issues surrounding lay readership of technical work. The use of differing terms confuses even experts (Not me, rather my lecturers when I ask them about issues in the literature) so the various terms will undoubtedly confuse anyone unacquainted with the literature.
A note on Wikipedia: I don’t know if I’ve mentioned my heavy use of Wikipedia references before but I think that in this blog a lay reference is fine and accessible for the interested reader who doesn’t want a long technical paper detailing the various arguments and counter-arguments presented by the expert.
Okay, so it’s ~13hrs late, sue me.
Bacteria –> Fish –> Amphibian –> Lizard –> Rat –> Monkey –> Human
As common a motif as any for evolution, this ladder (not the exact ordering or the creatures named but the concept at least) dates back to Ancient Greece (or at least so Wikipedia tells me :p *slaps wrist*). The idea basically being that animals are organised in a scale (The name for this ladder of life in latin was: Scala Naturae) from the least complex (bacteria) to the most and of course humans sit atop all because most complex life is best life.
But this view of life is terribly stunted in it’s vision, take for example these things, just take a look at the pictures and tell me, what is it? It’s actually a chordate, just like you and I, just like snakes, frogs, sharks, goldfish et.c., it’s a highly specialised version of one though and it’s like a barnacle in that it gives up the pelagic (Open sea) life to live attached to a rock and filtering out their food from the water around them.
These animals are perfectly suited to their environment, you are suited to yours, despite your supposedly ‘more’ evolved complex form, you could not possibly hope to survive doing what the barnacle or sea squirt does; neither, importantly, could their ancestors, the ancestor of the barnacle is also the ancestor of shrimp, crabs and lobsters so it’s best to think of a generic (pun intended (nested brackets for those who don’t get it, look up taxonomy and think about specific and general as words)) sort of crustacean. Despite the barnacle and sea squirt each losing features and simplifying down to a seemingly more basal form, they are in fact more evolved than their ancestors and far better adapted to their environments than their more complex cousins.
This concept is a general fallacy built into our minds or at least ingrained at a young age, I know of a time when I saw progress as the way things must be. When I was a child I was always told to ‘cheer up’ and to ‘smile more’ that ‘things will get better’. Despite there being nothing wrong really, I got bullied a little, but I think it’s just how things are at school. Most people are bullied. I should say that doesn’t mean that bullying is justifiable, what I mean is that my bullying was slight and no more than I would expect of being smarter than literally everyone at your school; I was before I moved to a different area where I was much closer to the mean and when I was bullied there, well I was the new kid and everyone had known each other since they could remember, I was an outsider and a weird one at that.
I took this general theme and applied it to evolution myself in my GCSE Graphics project where I re-designed monopoly into a game of evolution, though, really it was a Scala Naturae game and it didn’t really make evolution work how it was supposed to, a bit like another game I know about.
ANYWAY, putting my past where it belongs, the point I’m trying to make is that I was told that things would get better and that matched up with a general trend where we think that things are improving and getting better, I think this is a trend which began back in the ’60s with world wars and depression receding into the distance, science improving and young and exciting new culture being developed, everyone breathed a collective sigh of relief and it seemed things were going to be getting better, follow this up with the ’90s and ’00s of my own life and we’ve seen the internet take off, we’ve seen the fall of the Berlin Wall, and the end of the Soviet Union, these events have given us a sort of ‘things can only get better’ view, one popularised by Brian Cox no less.
This view seems to make the assumption that what must be true of science must be true for the history of things science has discovered, that since science has increased knowledge, improved technology, therefore, stuff should be getting better throughout the world. But just because we have managed to improve our human lives does not mean that on the geologic time scale, things must conform to the same rule.
Combine this with the radiation of groups of organisms as they diversified through time and it gives you a sense that most things around today showed up a long time ago and that was it, they never changed. Hence the old anti-evolutionist cry of “Well if we evolved from monkeys, why are there still monkeys?!” of course there’s more to it than that but putting on a sense of progress from when we evolved through to today gives credence to that old battlecry, if they were to understand that monkeys didn’t STOP evolving when the ape branch split off from them they’d be able to understand why monkeys are a far more successful branch than apes are (Compare number of species between Cercopithecoidea and the Hominidae, it’s clear which is the healthier bush*.
Finally, I’d like to say HEY look at me, I managed to get another post done in a consecutive week (sort of), let’s hope I manage to get a third one, and a fourth and so on until my posts number as many as the intermediate fossils between me and my most distant ancestor.
* Note: The Cercopithecoidea only include the Old World Monkeys of Asia, Africa and Europe, not the New World Monkeys so by that measure, Hominidae are even worse. (Taxonomists read on: I know, the New World Monkeys and Old World Monkeys as a group excluding the Great Apes is a paraphyletic group but shush, baby steps for people who don’t know as much as you, that is, people like me)
This essay was inspired by my recent reading of Stephen J. Gould’s book Eight Little Piggies along with some other books of his that I’ve read, I’m probably just repeating what he’s said in a less eloquent voice but hey, I think I’m getting better? No, okay then.
Take a minute and ask yourself that question, get a pen and paper and try to write a succinct and accurate answer… Harder than it looks isn’t it? It helps to try to define science within specific guidelines for example:
– As a belief system (including comparing it to other belief systems)
– As a way of knowing (including comparing it to other ways of knowing)
– Science and Technology
– Philosophy of Science
– The Scientific Method
Now first of all what I have to say is by no means the be all and end all of science, I don’t think I’d ever have the conviction to claim to be an authority on anything I’ve studied, regardless of how long I could spend studying it. Given the complex nature of this topic, I’m going to separate out these topics into separate posts that I will hopefully complete over the coming months.
This week, science as a belief system.
What can we truly say about the world around us? René Descartes famously stated “Cogito ergo sum”, the only real thing we can say is that our thoughts and feelings are real, that because we think, we must exist. But of course that’s not very helpful and not very practical, so humans have invented belief systems as ways of understanding our world, they may be based on a creed or dogma like religion, or they may be variants of various philosophies as defined those that dedicated their lives to thought.
Science as a belief system says that we can make certain statements about the world which we perceive. For example, the fact that it is built on rules and these rules do not change. If something seems to defy our rules then our rules are not accurate when compared to how the world actually is (or if you prefer our thoughts, theories and hypotheses do not fully explain what we perceive to be true). This is the basis of the Scientific method but I’m getting ahead of myself there. Science attempts to state and explain everything there is in the natural world, scientists seek to understand all the phenomena (Phenomenon (Singular): A fact or situation that is observed to exist or happen).
So science states that if something is tested over and over and there is a consistent result, then that is probably true, so if I jump up over and over, I’m going to fall back down and land (hopefully upright) again, this is true.
But why do things happen? Well that’s where we can bring in Occam’s Razor, that is, the simplest answer is often the right one, if there is a simple testable explanation, and it has been tested and evidence hasn’t contradicted it, then that is probably right. If something is a more complicated answer then it is probably wrong. This of course is secondary to the evidence. If two, as they are called hypotheses, have not been falsified, then the simpler one is probably the right one.
So what does science say about other belief systems? Well first off nothing in science says that you have to put to death anyone who doesn’t believe in science which in my mind immediately puts it above older more intolerant belief systems (if you get what I’m hinting at). Science makes no statements about other belief systems saving where those belief systems make statements about the observable universe. If a belief system makes a statement that is illogical then because science is based on logic it would reject that too.
Note that only where things contradict reason or have been shown to be not true is science at odds with alternative belief systems, believing science does not necessarily contradict a belief in any other belief system, religion or otherwise, it would be wise to have another belief system, for example a system of ethics and morals. While I am not religious, I don’t see any point in picking a fight with religion mainly because I see it as a futile ‘war’ on an extremely pervasive and ‘sticky’ ideology.
There is another branch of academic study that has not been discussed and that is the humanities. I know from personal experience that many believe and have believed myself for a time that Science was the greatest thing and anyone doing anything else were ignorant scum, harsh words. Where does this idea come from that makes science think it’s so much better than the arts?
Well a greater mind and speaker covered this concept in his wonderful book, “The Hedgehog, the Fox, and the Magister’s Pox” by the late Stephen Jay Gould published posthumously, this book looked at the ‘knowledge wars’ since the birth of modern science, he suggested that science, along with others follows the hedgehog in it’s style, having one very good way of doing things, this is good, but it restricts us in our ways of looking at the world so while it is important for scientists to be a hedgehog, humanity should be like the fox, using each different method for each different problem, science has no way of determining morals and so we should use a different method of ‘knowing’ something in order to decide morals.
This idea that we should see the different groups, not at war with each other, but complimenting each other, he called this idea consilience, I would highly recommend reading his book and deciding for yourself I may not have summarised his points as well as I could have. But the point of all this is that science is very good at what it does, the best in fact, but it cannot step beyond it’s bounds we have to find alternatives which are the most practical and useful. Where science cannot tread, we have to use a different vehicle for understanding.