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Sex and death
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Sex and death

Knew that catchy title would suck you in. A bit of the natural world to temper the virtual world. It's not very racy though, sorry. This is the story of a very ancient little living thing called Volvox. It's existed unchanged for a couple of hundred million years (I'm just paraphasing an old essay here btw, maybe some of it has been found to be wrong by now, dunno). It hasn't evolved because it is perfectly adapted to its place in the world. I read this thing that said we are the products of a long line of creatures that were out of step with their environment, which gave rise to new creatures, and on and on through time. So in evolution, it is the misfit that has always been the vehicle of creative change. I have no idea how accurate that is but who cares, it sounds good.

Anyway, if you magnify it a bit Volvox looks like a green marble. It revolves on one axis like a planet and swims around as purposefully as we make our way through the world. The green colour is from chlorophyll and it can be grown in a chemical solution, which suggests a plant. But it represents a stage of evolution where the distinction between plants and animals hasn't yet been made; it's neither one nor the other.

The cells on its surface look exactly like the one-celled creatures found in any pool of water, with an eye-spot, a nucleus, and 2 flagella to propel them through the water. At one time they were no doubt just a casual grouping of individuals, completely independent of each other. But now their flagella all beat in time, as if Volvox has some central brain that coordinates the movements of all its seperate cells, and they can't exist on their own.

Inside its body are 3 different types of cell. One type are the daughter colonies, identical to the parent, that will eventually bud off and form colonies of their own. Here's the sex bit. Another type looks a lot like the sperm of "higher" animals, and the last type is a sort of egg, much larger in size. Some Volvoxes produce both eggs and sperm, but in other species an individual will usually only produce either eggs or sperm. It's the first appearance of a distinction between male and female individuals. So Volvox invented sex, which is quite an accomplishment, but it also introduced death to the world of living things. An amoeba or a paramecium is immortal in a way; no new individual is ever produced because they just produce copies of themselves, and if conditions are right they can live forever. But Volvox, like everything since, has a built in expiry date and death is as inevitable for each of them as it is for us. This zoologist wrote "This is the first advent of inevitable natural death in the animal kingdom, and all for the sake of sex... Is it worth it?" I'm thinking his sex life probably wasn't the best.

Anyway, it's all just useless information but I find stuff like this is sometimes a good distraction when the human world gets too much. You look around and wherever there is no human head there is the non-human world of little things that are just barely alive, whatever life is. And to think that a few billion years ago the earth was the exact image of hell, with no life anywhere. How did it begin and what is it, and all that. I'm sure if we think hard enough about it we can figure it all out and enlighten the world.

Feb 13, 2013, 01:37