Ant Colony Optimization
History: Introduced by Marco Dorigo, ACO is a probabilistic technique for solving computational problems which can be reduced to finding good paths through graphs. They are inspired by the behaviour of ants in finding paths from the colony to food.
Overview: In the real world, ants (initially) wander randomly, and upon finding food return to their colony while laying down pheromone trails. If other ants find such a path, they are likely not to keep travelling at random, but to instead follow the trail, returning and reinforcing it if they eventually find food.
Over time, however, the pheromone trail starts to evaporate, thus reducing its attractive strength. The more time it takes for an ant to travel down the path and back again, the more time the pheromones have to evaporate. A short path, by comparison, gets marched over faster, and thus the pheromone density remains high as it is laid on the path as fast as it can evaporate. Pheromone evaporation has also the advantage of avoiding the convergence to a locally optimal solution. If there were no evaporation at all, the paths chosen by the first ants would tend to be excessively attractive to the following ones. In that case, the exploration of the solution space would be constrained.
Thus, when one ant finds a good (short, in other words) path from the colony to a food source, other ants are more likely to follow that path, and positive feedback eventually leaves all the ants following a single path.
Source: Wikipedia
So how does this apply to the optimizing your site?
Most times when a site gets coded an often overlooked element of site design are the internal links found on the site. Soo many times I have seen urls that say "Click Here". Imagine if you were driving on the highway and the sign only said "Exit Here".
How would you know which was the right exit? If they all said the same thing, we would never be able to get to our destination.
This is how the search engine spiders feel when you label your "Guide to Worm Farming" page as "Click Here". The robots are hungry for information and every part of your site should feed their appetite. Every link should be worded in an informative way so that the crawler can better categorize (and rank) your site accordingly.
Mother Nature is full of wonderful examples that can be applied to the web. There's a reason why ant colonies thrive, and if it works in nature, it's a good bet that your can transpose those same principles to the web.