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Question

Explain the theory of natural selection.

Answer 1

Natural selection is the process by which favorable traits that are heritable propagate throughout a reproductive population: individual organisms with favorable traits are more likely to survive and reproduce than those with unfavorable traits. If these traits have a genetic basis, then the genotypes associated with the favored traits will increase in frequency in the next generation. Given enough time, this passive process results in adaptations and speciation

Answer 2

Natural selection is a process that is distinct from evolution--in fact it's a process that was known long before the idea of evolution was developed.

Here's how it works. In the population of any species (I'll use wild horses as an example) each member of ths species is different. Using the example of horses, some will be faster or be able to run for longer distances (plus all kinds of other variations). Now, in any given environment, some of these variations are an advantage (or a disadvantage). A fast hors is more likely to survive while the slowest horse in a herd is likely to get caught by a hungry lion.

The result of this process, playing out time afer time in all kinds of circumstances, is that the members of a species who are best adapted to their environment are likely to survive--and reproduce (here, the fastest horses). So their offspring will tend to be just a little bit faster.

So what ends up happening is that the natural processes of living and competition between organisms tends to "select" the best fitted to survive, so that they pass on their advantages to their offspring.

What about evolution?
When Charles Darwin formulated his theory of evolution, he did so based on a lot of research. The core of his ideas rested on the observation that groups of a species (animal or plant) that were isolated from one another tended to change over time, becoming distinct and separate.He suggested that changes occured from time to time (usually small ones) in the makeup of these populations. If the changes became extensive enough, what you would end up with (after thousands or millions of years) is that the two groups would be so different they would no longer be the same species. Darwin wrote before we discovered DNA or genes--so he had no idea how such changes occured, he just had observed that they did--and for want of a better term, called them "mutations" (from the Latin word for change).

Where Natural selection and evolution meet--
Darwin already knew about natural selection--and he realized that it had an effect on how those changes he observed (which he called "evolution") played out. Whenever a mutation took place (pretty much a random process) it might be one that gave the organism a survival advantage--in which case the process of natural selection meant it would have a good chance of surviving--and passing on the mutation.. If a mutation put the organism at a disadvantage, it would probably be weeded out the same way. So, while natural selection has nothing to do with the process of mutation and evolution in general, its the factor that determines which evolutionary changes (mutations) survive and wich don't

The only other thing to remember about this to get the basics is that bot h natural selection and mutation arestatistical processes--meaning that is how things work out on average.
but they are only probablilities--and sometimes a statistical fluke will occur and a bad mutation will survive or a good one lost. The process isn't automatic.

Answer 3

Speciziation explains natural selection for organisms suited to live in a specific enviornmental niche. The Penguins can live in the Arctic and South Pole regions where it's cold. The Flamingos can live Tropical climates. The strongest and biggest don't necessairly always survive. The Dinosaurs were wiped out after a meteor hit our planet. Much smaller and weaker animals survived and multiplied. We are stronger than mosquitos. But, there are probably more mosquitos than humans and they've been here before us. So, they're better at surviving hard times than us. I think the same go's for rodents.

Answer 4

Ok. Natural selection, is the theory that the species with the best suited genotypes(genes that show themselves as evident, wether it be a stronger heart, bigger brain, body size, or even hardness of toenails) in a given population of a certain type of species, or competing species, becomes dominant or just plain survives. The other competing species, or group of competing animals of the same species, usually die out, or just wither away, to move to other places or get eaten by other animals.
Survival of the fittest in more scientific terms.
Natural selection might not just come out of a trait that is necessarily competitive, for example, The blonds of the human race are dying out, not because everybody is killing them, but because the blond gene is recessive.
Natural selection is responsible for the traits of the worlds species as we see them today. Even with the very first forms of life(not really life), the swarms of floating primitive DNA went through natural selection before they even evolved into classifiable living specimens.
Scott and Friends
P. S. Good luck

Answer 5

this is darwin's idea of evolution. you have always heard these words like thess "your special, try your best and you will succeed" but it is also a reality that only a few will succeed. this is the natural selection of the strong. so darwins puts this idea like "Only the strong species of animals will survive and the rest will be wiped out"

Answer 6

the animal who is most fit for its environment gets to survive, and thus procreate.