I'm not a creationist or an IDer, but this is a question I always wondered about.
If bacteria and other microscopic life reproduce at such a fast rate, then evolution must occur at a faster rate?
If so, how come I've never heard of colonies of bacterium evolving into new and more complex and organized multicellular organisms?
I'm not studying biology so maybe there's something wrong with my question itself.
Thank you for any answers.
If bacteria and other microscopic life reproduce at such a fast rate, then evolution must occur at a faster rate?
If so, how come I've never heard of colonies of bacterium evolving into new and more complex and organized multicellular organisms?
I'm not studying biology so maybe there's something wrong with my question itself.
Thank you for any answers.
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> If bacteria and other microscopic life reproduce at such a fast rate, then evolution must occur at a faster rate?
Faster than what? The rate of evolution depends on (among other things) the selection pressure acting on the population. So if a particular allele provides a large increase in the likelihood of survival or reproduction, then the frequency of that allele in the population will increase relatively quickly. If there are no such alleles providing large differences in survival or reproduction, then the pace of evolution will be slower.
> If so, how come I've never heard of colonies of bacterium evolving into new and more complex and organized multicellular organisms?
There are experiments, such as the Lenski experiment (which you can google) that show the evolution of novel characteristics in the population in a relatively short time. The evolution of multicellularity from bacteria, however, took billions of years and a very unusual combination of circumstances. First bacteria had to evolve into archaea, which is another group of unicellular organisms http://en.wikipedia.org/wiki/Archaea . Then particular archaea and bacteria living in close proximity had to evolve to become so symbiotic that the bacteria could live inside the archaea. Eventually these symbiotes evolved to become a whole new kind of cell - eukaryotic cells, with what once were bacteria evolving to become mitochondria (energy producers) for the larger cell http://en.wikipedia.org/wiki/Endosymbiot… . Later, certain eukaryotic cells evolved to become multicellular. Only eukaryotic cells have managed to do this, because their mitochondria put a great deal more energy at their disposal for the production of new proteins. See http://www.sciencedaily.com/releases/201… The first bacteria were around at least 3.4 billion years ago http://www.sciencedaily.com/releases/201… , and the first multicellular organisms evolved around 600 million years ago http://news.bbc.co.uk/2/hi/science/natur… , so you can see it took a while.
Faster than what? The rate of evolution depends on (among other things) the selection pressure acting on the population. So if a particular allele provides a large increase in the likelihood of survival or reproduction, then the frequency of that allele in the population will increase relatively quickly. If there are no such alleles providing large differences in survival or reproduction, then the pace of evolution will be slower.
> If so, how come I've never heard of colonies of bacterium evolving into new and more complex and organized multicellular organisms?
There are experiments, such as the Lenski experiment (which you can google) that show the evolution of novel characteristics in the population in a relatively short time. The evolution of multicellularity from bacteria, however, took billions of years and a very unusual combination of circumstances. First bacteria had to evolve into archaea, which is another group of unicellular organisms http://en.wikipedia.org/wiki/Archaea . Then particular archaea and bacteria living in close proximity had to evolve to become so symbiotic that the bacteria could live inside the archaea. Eventually these symbiotes evolved to become a whole new kind of cell - eukaryotic cells, with what once were bacteria evolving to become mitochondria (energy producers) for the larger cell http://en.wikipedia.org/wiki/Endosymbiot… . Later, certain eukaryotic cells evolved to become multicellular. Only eukaryotic cells have managed to do this, because their mitochondria put a great deal more energy at their disposal for the production of new proteins. See http://www.sciencedaily.com/releases/201… The first bacteria were around at least 3.4 billion years ago http://www.sciencedaily.com/releases/201… , and the first multicellular organisms evolved around 600 million years ago http://news.bbc.co.uk/2/hi/science/natur… , so you can see it took a while.