|MadSci Network: Evolution|
Evolution works through the selection of traits that give an organism a reproductive advantage over its competitors. In any population there will be differences between individuals which have an impact on their ability to compete and procreate. Through the process of natural selection, those traits which confer an advantage to individuals in their ability to reproduce will be selected for. In the case of nervous systems as it applies to plants the question from an evolutionary point of view would be how would it give a plant an advantage? Nervous systems serve to provide information about the world through the senses and control movement (among many other things). This is important for an animal because to survive they must eat other living things, thus they need to sense those other organisms (through eyes, ears, noses etc.) and then be able to coordinate movement to catch the other organism (or if herbivore simply to find edible plant material). Plants do neither. They do not need to eat other living things (venus flytrap notwhitstanding) and do not move. So a nervous system instead of being an advantage would be a disadvantage because precious energy would be spent on something useless. hope this helps, gabriel vargas md/phd References Biology by Neil Campbell
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