A question about evolution If evolution is primarily about survival of the fittest, why did'ntt it stop at being something like the extremely fit, highly adaptable and rapidly multiplying virus, or bacteria? Are not micro-organisms the ultimate survival machines?
Actually, most life is single-celled. Multi-cellular life is not the rule, it is the exception, and comparatively new also. So you are correct, micro-organisms are the ultimate survival machines. Multi-cellular life developed through utilizing other niches, areas that required a more complex structure to be able to be profitable (in the sense that it can feed life). And thus it started, life feeding on life, getting more complex as the arms race between competing structures (species) intensified. Not that I'm complaining. It did lead to us humans (and cute feline furballs ) so it must all be good
They are master species. This is why I find it interesting that they bothered to evolve, I dont want to come across as making the mistake that i expect evolution to have a 'final' point in its evolutionary process, that would simply be a common fallacy. A virus, for example, is no different to a human as far as consuming resources is concerned. Both are ultimately controlled by the resources they consume. Both can potentially drive themselves to extinction. So my question is, why does evolutionary pressure bother to form other types of life when it could seemingly stop with the beautiful structure of micro organisims.
Um evolution is not a concious being, it has no concept of when to stop doing anything. Should the sun decide to stop shining on the desert because it's too hot there already?
To fully understand the answer to this question, you must first have some knowledge of evolution itself. "The survival of the fittest" is a dillution of Charles Darwin's THEORY of Natural Selection. Now, before I begin to share what I know of the process, let me explain my emphasis on the word 'theory'. Evolution is a fact, this was proved by Erasmus Darwin--the grandfather of Charles, in 1794. The reason why I emphasized the word theory, is because Natural Selection is Charles Darwin's explanation of HOW evolution occured, and IMO a perfectly logical explanation, but albeit, still classified as a theory and will probably remain so as long as certain dogmatic structures hold public sway... Anyways, getting back to evolution. The process of Natural selection is such that members of a certain population most fit to survive do so, while those not fit to survive, inevitably do not. So why did microorganisms not stop evolving, as they appear to be the perfect organisms? Well, I am ignorant as to the EXACT answer of this question, but I would infer from what I do know that not every organism evolved in exactly the same way. So, it is reasonable to say that two separate populations within the same species, located in different areas with different resources would have evolved differently from eachother. Knowing that there are so many different enviornments on the earth, we could not expect that one particular group could have evolved to survive in every concievable condition all the while dominating each other separately evolving sub-species group, or even another species. Now, take the minute evolution of single celled organisms and stretch that over BILLIONS of years...and somewhere along the line, with the changing climates on earth, the microorganisms continued to evolve to the point where it was not viable for some species to remain single celled. I hope that helps to answer the question a little...Like I said earlyer, my knowledge on this subject is limited...but this is what ive got!
Id have to say the answer -at least in part- lies in cooperation. Some things like jellyfish or sponges behave more like colonies of single celled organisms rather than 1 multi-cellular organism some ppl theorize that even some of our cellular organelles are in fact alien. For example, mitochondria have their own DNA, some believe this shows that a long time ago the mitochondria was its own cell or part of another cell and was taken into another type of cell and happened to cooperate and benefit one another (much like 2 animals would share a symbiotic relatinship) these 'communites' were the training wheels for multi-cellular life The largest advatage to multi-cellular living is speacialization. you canthink of our body as a large multi-celled organism. think of each muscle or organ as its own cell so instead of having 1 'human cell' that has to digest and metabolize and excreet waste, we have a human organism with specialized cells arranged in bunches to do its own specialized task its a fairly logical step if you think of it that way, not much different from the assembly line concept, if you specialize, you become more efficient i wish i had more input, but i havent been in Bio for a few years
Just a thought, slightly off-topic: Species, like some sharks, reached their peak of evolution a few million years ago and haven't changed since... And: There's an organism under recent research that's turned out to be very interesting. It lives symbiotically on coral reefs and has been found to have a 100 times more DNA than humans. 100 times more potential for change and adaptation. I'll try and find the link, scientists said they'd never seen anything like it before... MelT