Natural Selection

according Darwin evolution is a very slow process .......he says that generation after generation there will be a minor change in the organisms which arises due to the environmental influences and the need of the organisms......

Natural selection is limited by the ability of the population to produce variation. This in turn is limited by the amount of mutation a lineage can survive. Too many mutations, and the effect becomes detrimental. Too few, and the population may not be able to adapt fast enough to changing circumstances and go extinct.

Well, scientists, for starters. And most higher educated people. And a good portion of the general populace as well. People who don't accept natural selection generally reject it because they don't know or understand what it is, or because they don't want to know what it is for religious reasons.

The four stages are:

Overproduction, Genetic Variation, Struggle to Survive, and Successful Reproduction

Quite simply, the better an individual is able to mimic its surroundings, the less likely a predator is to spot it. This gives it a better chance of mating and passing its genes on to the next generation.

no

there is no genetic variation for natural selection to act upon

The primary driving force behind evolution is the environmental pressure, which encourages or discourages certain physical or behavioural adaptations to best fit the environment.

Natural selection is not a thing that acts on populations, it is a tendency for harmful genes to not be passed on (die out) and useful variations to thrive and become common.

Cultural evolution is the phenomenon whereby cultural ideas, notions, views, etc. propagate throughout populations, like alleles propagate throughout population gene pools in biological evolution.

Some propose that the way these ideas propagate throughout populations is similar to the ways of biological evolution, in that cultural ideas (or memes) are subject to a kind of cultural selection, that determines how fast they spread, and to what degree.

Simple observation. Look at the many species that have evolved to specialize to a specific environment. Let's say you have daisies growing in your yard. They will have some natural differences in them. Some may be taller than others. You mow your yard on a regular basis. Many of the taller ones can't survive long enough to go to seed. More of the naturally short ones survive to "mate" with other short ones and soon enough their genes come to dominate in that environment. Eventually you wind up with a species of short-stemmed daisies. However, that fact that this is an observable truth does not prove the idea that one species evolved from another (the theory of evolution). While it suggests that this is possible, there is a woeful lack of evidence to prove it. Even Darwin knew this and wrote about it. Those short daisies are still daisies.

The theories are evolution deal with the fact that every being on the planet today came from a now-extinct species. This goes for humans as well. Scientists believe that humans evolved from now-extinct mammals during the Late Cretaceous period. Evidence proves people came from a member of the gibbon family.

'competition between mates' as the words suggest mean that organisms in a habitat compete for their basic needs including mates. three tigers could be competing for one tigress. and the one that's the fittest wins (survival of the fittest).

when thinking about 'natural selection', think evolution. this is to say, over time, the traits that are strongest in an organism gets passed on from one generation to another. what you get as an end result is you may notice the weaker traits have extinguished while the stronger traits have become more obvious.

now the correlation between the two: imagine having two tigers fighting for a tigress. the stronger one with sharper claws and teeth wins the tigress over. this simply means the weaker tiger probably had some flaws in its traits. and because this winning tiger has strong traits, they get passed on and that's evolution (natural selection).

Natural selection occurs when four conditions are met:

1. There is variation among individuals.

2. That variation is at least partially heritable.

3. That variation is linked to differential reproductive success.

4. More individuals are born than can survive and reproduce.

The principle of natural selection is that the fastest or the strongest (in other words the most skill at a trait) would be the most desirable mate and the weak ones that lacked these skills or mutations like thumbs would not be mated with. So the principle of natural selection is we will always find the strongest, fastest or the most intelligent or other advanced traits more desirable.

Survival of the fittest is a not quite accurate phrase for natural selection. Natural selection is,

The non-random survival and reproductive success of randomly varying organisms.

Natural selection creates a stronger species that is able to live longer and produce more. It continues to work because after a few generations, the traits will become common in the population.

Comparative DNA samples from chimpanzees and humans show very well the concept of evolutionary common ancestry. Aside from that, the differences in DNA among organisms, especially at certain loci, show how long two, or more, organisms shared common ancestry.

Variant traits that increase the number of offspring become common in a population, causing the overal morphology and behaviour of the population to continuously shift to give the best reproductive chances for any given environment.

As spices develop they create variations. That means differences creep in. Those differences are called variations. Every now and then one of those differences makes it so that a particular individual or group of individuals can better adapt to a particular place.

The similarity between natural selection and selective breeding is that they both produce changes in plants and animals.

Abiogenesis, or more commonly known as the origin of life itself, is not part of Darwin's theory of evolution.

The phenotype of organisms determines the way they interact with one another and with their environment. The way organisms interact with one another and with their environment determines how well each organism is able to compete for resources and mates - what the chances are of that organism successfully raising fertile offspring, in other words. Such offspring will likely carry the genes that give them their parent's successful phenotype. So over the generations, the genes that produce such successful phenotypes will become more numerous in the population, causing a shift in the average of phenotypes towards this successful phenotype.