what is evolution?

Answer 1

Evolution is the (very widely accepted) belief that species evolve over time true a process of natural selection. The idea existed in ancient Greece, but did not gain a wide audience until the publishing of "The Origin of Species" by Charles Darwin.
Darwin thought that species evolved through a natural process he called natural selection. This means if an animal is born a certain way, with longer legs for example, that will be an advantage or a disadvantage for this animal. In other words, it increases or decreases that animal's chance of survival. If an animal survives longer, the chances are better that that animal will have offsprings (babies) and that these offsprings will grow up to have offsprings of their own. So if it's an advantage to have long legs, over time, this will encourage such an animal to have longer and longer legs, as those with long legs survive. And, over a long period of time, something that first resembled a gazelle could look a lot more like a giraffe. Eventually, species branch out, which means that while one group of descendants could evolve to become giraffes, another group might also have survived, but they gradually learned to live in the mountains instead and they developped hooves and strong leg muscles. These could be mountain goats. Over time, they become so different from each other that they are no longer the same species, which means they can't have offsprings together. (There's a genetic reason for this, but I don't want to get into that).
So that's basically Darwin's theory. Today, the theory (like all scientific theories) has been refined and much worked upon. Scientists tend to take a whole ecosystem (All plants and animals in one area) more into consideration rather than just one species at a time. Although Darwin thought competitiveness was the key, evolutionists today recognize cooperation and kin survival (doing something to help your brother, or child survive) play a larger role in evolution than Darwin thought.
Also, the role of genetic mutations is much more prevalent in the theory today. A genetic mutation is an error in reproducing the genetic code (The basic elements that tell a cell how to grow and become a full animal). Normally, mutations are a bad thing. But once every little while, one animal actually gets lucky and is mutated in a way that's an advantage to it, and gets to pass that on to its offsprings, much as in classical Darwinism.
Hope this helps.

Answer 2

Excellent question!! "Descent with modification"
Evolution is change in organisms over generations. Offspring differ from their parents in various ways. When these differences are helpful, the offspring have a greater chance of both surviving and reproducing, making the differences more common in the next generation. In this way, differences can accumulate over time, leading to major changes in a population.
Darwin's explanation of the mechanisms of evolution relies on his theory of natural selection. The modern theory of natural selection incorporates five basic ideas:

1. Organisms will produce more offspring than their habitat can sustain. There will be a "struggle to survive".[1]
2. Not all the offspring will be identical.
3. Some of the differences between the offspring will be due to variations in their genetic makeup, the "code" that determines each organism's inherited traits.
4. Genetic variations that help an organism to survive and reproduce will be passed on to the next generation more than genetic variations that are unhelpful.
5. Over time, helpful genetic variations will accumulate until a new species results.

There is a subtle point to be remembered. Natural selection acts on the individual, evolution affects the species. Think how there are no brown bunnies in the arctic, and if there was one born, how quickly he would be eaten! Likely before he could have any brown bunny babies of his/her own.

Answer 3

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

Through the process of natural selection, there will be decreases in certain gene frequencies and increases in others. Combine that with mutation and changes in the actions of regulatory genes, and over long periods of time you can speciation. I think if people stopped implying that evolution means people=monkeys, a lot more people would accept it.

It just makes so much sense!!!!!!

Answer 4

A theory that explains how life beings are adaptating their design to the enviromental conditions. The mechanism is simple: the characteristics of parents are transmitted to their descendence, and those which are the best fitted will survive with a higher probability and have new offspring. Small spontaneous changes, hereditary, will be transmitted if they are good to the struggle for life.

Answer 5

Evolution is the gradual development of species from earlier forms,as an explanation of their origins.

Answer 6

Its the theory that monkeys turned into people.

Answer 7

it means CHANGE......it means GROWTH