(November 26, 2016 at 3:20 pm)The Joker Wrote:(November 26, 2016 at 3:19 pm)robvalue Wrote: No, it isn't. And "evolving upwards" is a meaningless phrase. Why not go get a science book.
So define evolution how do you see it as?
Instructions on how to develop a phenotype (humans, animals, bacteria, solutions in a computer) are stored in a genotype (chromosomes, a string of real values in a computer etc) . Different operators are applied to the genotype; crossover, mutation and duplication. Crossover is when a proportion of each parent's genotype is recombined to form a new genotype. If there was only crossover then all variation would eventually be removed in a population even without natural selection.
Mutations of individual parts of the genotype increase variation within the population. Most mutations are deleterious but a few of them are beneficial. The few beneficial ones are more likely to spread throughout the population over many generations because carriers of the mutation are more likely to breed successful offspring. The larger the mutation the more likely it is to deleterious. This is why smaller mutations are better and why macro-evolution works by micro-evolution.
Duplication can also occur in the genotype. This opens up new areas of the search space because the duplicated parts of the genotype can be mutated and can perform a different function. This only works for neutral duplication though that does not lower the fitness of the genotype. But this is one way in which complexity can grow over time.
Using these operators, the population traverses a fitness landscape because weaker phenotypes are less likely to produce off-spring whereas the stronger phenotypes are more likely to. So each generation the population moves as a whole to higher points on the fitness landscape as the fitter genotypes are used to produce stronger phenotypes that breed more.
