Tree of Life

In the beginning was soup. A soup of molecules and assemblies of molecules. Then one produced a copy of itself and became the first organism.

Now, an organism doesn’t actually exist. Nature didn’t say, “I know, I’ll create an organism today.” It just happened. We have since invented the word for a molecule that reproduces, grows, develops and does other whizzy activities that separate it from a crystal.

So, by our definition the first organisms were in fact two – the parent and the child – and both were capable of producing copies. But imperfectly. The copies were prone to error, usually fatal error but, when not deadly, new types of organism arose.

One day, two organisms discovered sex. Hooray! Now we could invent a new word – species, which means a group of organisms that can have sex together. And they did. And apart from being more fun than going solo, sex allowed children that were variations on their parents, but variations with a good chance of survival. Oh, errors still existed, many still fatal. And they still gave rise to new types of organism but with nowhere near such proliferation as sex.

Sex was great and in time it produced a child that couldn’t have bred with the act’s original discoverers. The second species! Again, by our definition. Nature wasn’t thinking along these lines. Nature doesn’t think.

Now things went a bit mad, on a geological scale. For three and a half billion years species popped up like crazy, like a tree sprouting branches, and twigs and leaves. And we’ve invented words for all these bits of the tree. If a leaf is a species, genus is a twiglet of them; family, a twig of genera; order, a branch of families.

Nature wasn’t organising it like this. We were describing it so, even before Darwin. We got it wrong in many places, still do, even with our evolutionary knowledge. We have entire branches misplaced on the trunk but modern DNA studies are fixing this. One day, we’ll know how the Tree of Life fits together.

If we haven’t dismantled it beforehand.

Evolution continues now. We have words for those organisms that may be breaking away from their parents. A subspecies, or a race, shows physical differences but still interbreeds. Maybe. We’re getting those wrong too. Indeed we still have similar looking species incorrectly “lumped”: until recently such familiar birds as marsh and willow tits, and water and rock pipits were not recognised.

So, from a soup to a tree that was in vigorous health and still growing until disaster struck about 100,000 years ago. Not its first disaster, but the sixth and the one that threatens it like no other.

All because an ape learned to kill.

Related posts:

1. Tree(s) of Life, 2008
2. Tree Sparrows, Martin Mere
3. Birding for…