As a vegan, I get a fair amount of weird shit when this particular lifestyle choice of mine comes up in conversation. I’m in two minds about that: on the one hand, it’s a choice of mine, and not exactly a common choice, so I understand that people have difficulty with it. On the other hand, most arguments against veganism betray ignorance, and my tolerance for stupid isn’t very high these days1.
One of those arguments that gets thrown up once in a while, probably because it sounds catchy, is “but it’s survival of the fittest!”.
Well, no, it’s not. By using that argument, you betray ignorance of what survival of the fittest means.
You see, the thing that people always fail to grasp is that survival of the fittest, or natural selection, or evolution, or the process by which one species comes to dominate and another dwindles is a statistics game.
It is not applicable to individuals.
To illustrate that, let’s take a look at giraffes. These tall antelopes have enormously long necks that allows them to graze the nutritious leaves off the top of trees, while other antelopes that cannot reach that high can only graze the less nutritious grass on the ground. That’s a beautiful example of the strange mutations evolution produces.
So cast your time back to the time where giraffes didn’t yet exist, and the common ancestors to them and other antelopes, let’s call them proto-antelopes, roamed the plains of Africa. If there were plains at that time, of course. Not that it matters all that much to this post.
There then must have been a proto-antelope with a freakishly long neck that, because it seemed easy for it, reached for leaves higher up on trees than it’s brethren. It bred, and produced long-necked offspring, which in turn produced more long-necked offspring. If long-necked proto-antelopes bred with long-necked proto-antelopes, they likely produced longer-necked offspring, until at some point they were giraffes.
So far, so good. Now let’s ask ourselves this question: is a long neck advantagous to survival?
It might appear obvious that the answer to that would be “yes”, but really, it’s not. It happens to be advantagous only because the first long-necked proto-antelope lived in an environment where there happened to exist leaves slightly out of reach of it’s brethren which happened to be more nutritious than other food. It also happened to be the case that a longer neck did not impede this particular proto-antelope’s ability to attract a mate, or it’s ability to look after offspring.
In other words, there are a ton of factors involved that might be linked to this proto-antelope’s different physiology, but that do not absolutely have to be. Change any of these facts, and the long-necked mutation might prove to be a disadvantage. In the face of that, it becomes impossible to speak of one mutation as advantagous to survival; at best, it’s a statistical fluke.
We can only establish in retrospect whether a mutation was advantagous to survival in a very specific environment by the fact that there exists now a species of long-necked antelopes we call giraffes. What differentiates the statistical fluke from the new evolutionary branch is that it occurred often enough and was successful enough that it’s now well established.
For each evolutionary branch that occurs, many thousands of mutations fail. If you do something different from everyone else, or look different from everyone else, we’ll only know many generations down the line if that’s a successful or unsuccessful mutation, even if you live a long and healthy life and produce many offspring.
So while survival of the fittest must start somewhere, with an individual or a group of individuals, the individual does not make the evolutionary success; it’s a ton of factors outside the individual’s control that do that, and it takes generations to establish success or failure.
But, one might argue, the fact that giraffes now exist does prove that long necks are an evolutionary advantage. Right?
Well… again, no. It’s true that long necks seem to be a good enough thing for african antelopes that some stuck to that particular mutation and cultivated it. At the same time, there are many species of antelopes out there. Let’s quote Wikipedia:
The giraffe is a protected species in most of its range. The total African giraffe population has been estimated to range from 110,000 to 150,000.
The estimated population of nilgai in India is approximately 100,000. Wild populations also exist in Alabama and Texas where they have escaped from private exotic ranches. The Texas population is estimated to be around 15,000.
The Thomson’s gazelle is protected in a number of parks in its range. The population estimate is around 550?000.
The Mongalla gazelle is rather safe from extinction compared to other species, due to its harsh habitat, which makes exploitation and poaching difficult. Even though it has a very narrow range, being restricted to southeastern Sudan, it exists in high densities and there are currently 100,000 to 278,000 individuals left in the wild.
The Rhim Gazelle (Gazella leptoceros), also known as the Slender-horned Gazelle or the Sand Gazelle, is a slender-horned gazelle, most adapted to desert life. There are less than 2500 in wild.
I’ve pretty randomly followed links from Wikipedia’s antelope article to find those quotes. Unfortunately, not all articles list the estimated populations of each species, but these here give a good overview. The upshot? Yes, giraffes are more successful than other species of antelope, but they’re very clearly not the most successful.
In other words, evolutionary success is not a black and white thing, it comes with many shades of gray.
Incidentally, the picture painted by the numbers above is intrinsically flawed: most of the species whose very low popualation numbers I quoted aren’t so rare because they don’t fit their environment, they’re this rare because of poaching. Nothing to do with natural selection, not even in the slightest.
- Note that I don’t mean a lack of intelligence when I use the term stupid, I rather specifically mean a lack of knowledge combined with a lack of will for acquiring it. [↩]