Natural Selection

Mutations are believed by many evolutionists to provide a means for variablity in some of the characteristics of a species. For example, extra fingers and toes. However, since all mutations are DNA-destructive and result in a loss of information, increasing complexity from mutations is believed by many to be impossible. This is especially true if one subscribes to Information Theory, which states that information only comes from greater pre-existing information. Extra fingers only demonstrate an error in creating the correct number of digits, not additional information.

If a certain variation provides an advantage for an individual (or inter-breeding group) they these individuals will survive and breed where all others will die. This is natural selection (not evolution). The offspring of the survivors will all carry the traits of their parents. Therefore, the fittest will tend to thrive, but not change into a different species, at least not through this mechanism.

Natural selection is the nonrandom survival and reproductive success of randomly varying organisms.

The organism that is selected leaves more alleles of his progeny in the populations gene pool and evolution is just the change of that allele frequency over time in populations.

The men Charles Robert Darwin and Alfred Russel Wallace are the co discoverers of the identified theory of evolution by natural selection.

Its a chicken and egg situation. Adaptation is the response to Natural Selection, and Natural Selection is the response to Adaptation. They both operate by the principle: the members of any species that are best adapted to their environment are the ones most likely to survive and reproduce the next generation, where the process repeats. That does not mean the strongest or most aggressive, they often get themselves killed off.

Yes, traits that are phenotypical in nature and confer some survival and reproductive advantage, then the alleles that gave rise to these traits become more frequent in the populations gene pool and evolution takes place.

So, natural selection is acting on genes in the individuals and population are evolving from this process.

Natural selection is more of an evolutionary factor than a stabilizing factor, but one could argue that the end result of evolution is an organism that is perfectly adapted to its ecological niche, in which case stability will result.

Natural selection is the most powerful driver of evolution and it is the only mechanism of evolution ( genetic drift and gene flow are two other mechanisms ) that leads to adaptive change.

Natural selection is the nonrandom survival and reproductive success of of randomly varying organisms.

Evolution is the change in allele frequency over time in a population of organisms.

They both involve the principle of differential reproductive success. Only in one case, the reproductive success is determined by mindless congruence between phenotypic attributes and the environment, and in the other case, humans make the determination what traits should propagate.

The individual, or the genes of the individual.

All organisms are variants in phenotype and behavior. So, natural selection is the immediate environment these organisms are in and those that survive and reproduce better in this environment leave more descendants which carry the genes that promoted that survival and reproduction advantage. Then those genes are more represented in the populations gene pool and this is evolution.

Adaptation are the physical or the behavioral traits that make an organism better fits to its environment while the Variation usually comes from random mutations. Mutations are iniatially cause by a new heritable traits.

The presence of predators

Limited food-APEX

Natural selection is the process by which certain traits that provide a reproductive advantage become more common in a population over time, leading to evolutionary change. Evolution is the overall change in a population's genetic makeup over successive generations, driven by mechanisms such as natural selection. In essence, natural selection is one of the primary mechanisms through which evolution occurs.

1) A dominant male (alpha-male) takes whatever female he desires, while inferior males in the group can't choose, such is common among apes.

2) Two creatures exist in one environment, but a drought comes. Only the creature that can live through the drought survives.

There are plenty more examples, but this should give you an idea of what natural selection is.

There are two questions here; but if we look at the first one (how the eye evolved), the second one will also be answered. The simplest "eye" is simply light sensitivity. For example, some simple sea organisms can only distinguish between light and dark; if it's dark they shrink - some cells on their bodies are light sensitive and it triggers the response. It's obviously basic but better than no sensitivity to light at all. The next stage is a light sensitivity with some indication of motion; again some sea organisms have just that - some extra processing indicating which cells "see" the dark area first. Again, this is better than simply having light or dark sensitivity. One can see from this, that its possible to imagine lots of "next steps" - speed as well as direction, different directions, two eyes to be able to estimate direction, layers of transparent cells to form lenses in front of the light sensitive areas and so on. What's surprising is that examples can be found of most of the "intermediate" stages. A key point is that there's no "final" target that evolution is aiming for; the next stage is reached because the offspring that have more of the next stage present will tend to survive to reproduce and eventually a new species will arise that all have the next stage. Because modern eyes are essentially the result of millions of minor improvements of earlier models we've ended up with some odd results; in our own eye the retina is essentially back to front; the nerves which lead off to the visual context are in front of the light sensitive cones and rods - also if we wanted to design an eye, we wouldn't have a blind spot where the optic nerve joins the eyeball. The "why did the eye evolve" part of the question is that each step provides an advantage over not doing it.

Natural selection can help creatures adapt to their enviorment. Sometimes this can cause unwanted problems.

It shows natural selection by showing how different birds have adapted over time to continue living, and the birds which didn't adapt, went extinct.

Natural selection leads to evolution by giving the organism that is best suited for the area to thrive. Thus those who not suited for the area die off and evolution moves forward.

Evolution occurs via natural selection when certain traits become more favorable in a population over time. This is typically due to the environment or natural selection pressures in the population. Natural selection works by favoring individuals with traits that are better suited to the environment while those with less favorable traits may die off or be less likely to reproduce. Over time these favored traits become more common while unfavorable traits become less common. This process eventually leads to evolution as the population changes to adapt to its environment.

The three main components of natural selection are:

• Variation: Individuals within a population have different traits
• Inheritance: Traits are passed from generation to generation
• Differential Reproduction: Traits that are more favorable are more likely to be passed on

Natural selection is an ongoing process as the environment is constantly changing and influencing the traits of the population. It is important to note that natural selection is not a directed process and does not necessarily lead to a specific outcome. The result of natural selection is determined by the environment and the traits that are favored in the population.

when there is competition

Environmental pressure. Amongst a certain population of a certain species, there will be many different mutations which developed and were passed on evenly due to neither being beneficial nor detrimental.

Any change to their habitat can be considered an environmental pressure. A drop in temperature, invasion of a competing species, etc. Natural selection will occur, as those with now-beneficial mutations are more likely to pass their genes on.

The population has not reached carrying compacity is correct on apex

The final decision on which offeror will be selected

Natural selection is like a filtering system for living things. There is naturally occurring variation but there isn't space and resources for every living thing born. So those who are not able to survive die out for some reason. Most importantly, some don't pass on their faulty genes, so there is a "generalised (and I use that term loosely here) better outcome in the gene pool.

It's a cruel mechanism, but vital to keep species from continuing to change and not die out due to the accumulation of bad genes or traits that would otherwise hinder them in competition with another.