5.17.2007

Evolutionary thought experiment

So I was thinking about the missing bee problem and started thinking about what could be done if the bees became extinct. This would be beyond catastrophic and could bring about a quicker mass extinction than anything we have yet imagined. So, we would have to do something and what if that something was to create robot bees that flew around transferring pollen from one flower to another (just work with me here). Obviously the robot bees wouldn't need to actually collect the nectar of the flowers since the only purpose of nectar is to lure bees to the flowers to unwittingly transfer pollen. Ok, so now we get to the actual question, would plants evolve to no longer produce pollen? I mean, producing nectar requires energy and any plants that didn't produce nectar could direct that energy towards producing more flowers. This would give those plants an advantage over the nectar producers because they would be able to produce more offspring. Sounds like the answer is yes doesn't it? But if I haven't yet squandered any authority I might have by mass extinction talk and robot bee talk, the answer is... sort of.

There are two main reasons why the answer is sort of. First, evolution is a game of pressure, both positive and negative. Being able to produce more flowers would be positive pressure for the non-nectar producers, but because the robot bees would still service all of the flowers equally there is no negative pressure on the nectar producers. This would result in what I call passive evolution, the non-nectar producers have an advantage but it's only in the numbers game. This would probably result in nectar producing becoming a recessive trait (this is a massive generalization, I don't think anyone knows if genes can change their dominant-recessiveness and if they can how it occurs).

The second reason is the mechanics of nectar production. The most likely scenario is that multiple genes are involved, but for argument's sake let us say that there is just one. The first question is, is there already a recessive non-nectar gene? Possible but not very likely, there would be incredible negative pressure on that gene. Any plants unfortunate to exhibit the trait would only reproduce through randomness (drunk bees bumping into the flowers after visiting the nectar producing neighbors) or bee attraction via other stimuli (bees being attracted by flower color and not by the more powerful nectar attraction). So, recessive gene possible but unlikely due to the huge positive pressure of nectar producers and the huge negative pressure of non-nectar producers. The second question to ask regarding the mechanics of nectar production is, if there is not already a recessive non-nectar gene how likely is it that a mutation would create one? Not too likely. First, we've already made the unlikely assumption that only one gene is involved, then we have to make the equally unlikely assumption that one mutation would turn off nectar production.

So, what we have is, if non-nectar producers exist they will have very slight advantage which may eventually result in their dominance, if they don't currently exist they may come about randomly and eventually become dominant.

Which brings us to the real point of this whole convoluted rambling: evolution is crazy complicated. People who say they don't believe in it have no fucking clue what they are talking about, they don't believe in it because it is too complicated for them to understand. The majority of people who believe in it simply believe in it, they don't really understand it. Some people such as myself (I was studying to be a geneticist or evolutionary biologist in college) see that most people don't understand and see some of the mistakes people make but only a very small minority really have a good grasp on it. I mean, I know I said some things above about which an evolutionary biologist would say "You're right but not for the reason you think," or "you're wrong about this assumption." And the final kicker is that even those who really know what they are talking about would readily admit that there is a lot that they still don't understand.

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