What was Charles Darwin's Theory of Evolution?

Answer 1

Charles Darwin's theory of natural selection applies to organisms who adapt to their environment better than others and survive to pass on their traits to offspring. Due to variation in their genes, may be caused by mutation but rarely so, organisms are able to adapt to their environment. If they don't adapt well they die. If they adapt to their environment it means that they have fought for their survival and are now able to pass on their variations to their offspring and make them stronger. Often as a result a new species is formed due to the accumulated differences.

There are three types of natural selection: Directional, disruptive, and stabilizing selection. In directional selection only one extreme genotype is favored to pass on. Meaning the environment chooses one genotype to pass on. An extreme genotype for example would be either SS or ss for sickle cell, either the genotype for sickle cell is passed on or the non-sickle cell genotype is passed on. In disruptive selection, a disruption separates similar organisms causing the favoring of two extreme genotypes. For example both SS and ss are favored to pass on. In stabilizing selection only the middle genotype is favored meaning Ss which is carrier of sickle cell.

Natural selection is when the environment determines which alleles enable organisms to survive.

The theory of natural selection states that traits in a species become more or less prevalent depending on environmental pressures that select either for or against such traits.

Individuals that have traits that better suit their environment are more likely to survive.

Darwin broke down the process into 4 steps:

1. individuals that make up a population vary in their traits

2. some of these trait differences are heritable

3. in each generation, many more offspring are produced than can survive. Only some individuals survive. Of these, some will produce more offspring than others

4. Individuals with certain heritable traits are more likely to survive and reproduce.

Natural Selection occurs when individuals with certain traits produce more offspring than do individuals with certain traits produce more offspring that do individuals without those traits.
when organism adapt to the environment they will be likely to survive and produce healthy offspring.

Answer 2

Darwin's Theory of Evolution is the widely held notion that all life is related and has descended from a common ancestor: the birds and the bananas, the fishes and the flowers -- all related. Darwin's general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected) "descent with modification". That is, complex creatures evolve from more simplistic ancestors naturally over time. In a nutshell, as random genetic mutations occur within an organism's genetic code, the beneficial mutations are preserved because they aid survival -- a process known as "natural selection." These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the result is an entirely different organism (not just a variation of the original, but an entirely different creature).

Darwin's Theory of Evolution - Natural Selection

While Darwin's Theory of Evolution is a relatively young archetype, the evolutionary worldview itself is as old as antiquity. Ancient Greek philosophers such as Anaximander postulated the development of life from non-life and the evolutionary descent of man from animal. Charles Darwin simply brought something new to the old philosophy -- a plausible mechanism called "natural selection." Natural selection acts to preserve and accumulate minor advantageous genetic mutations. Suppose a member of a species developed a functional advantage (it grew wings and learned to fly). Its offspring would inherit that advantage and pass it on to their offspring. The inferior (disadvantaged) members of the same species would gradually die out, leaving only the superior (advantaged) members of the species. Natural selection is the preservation of a functional advantage that enables a species to compete better in the wild. Natural selection is the naturalistic equivalent to domestic breeding. Over the centuries, human breeders have produced dramatic changes in domestic animal populations by selecting individuals to breed. Breeders eliminate undesirable traits gradually over time. Similarly, natural selection eliminates inferior species gradually over time.

Darwin's Theory of Evolution - Slowly But Surely...

Darwin's Theory of Evolution is a slow gradual process. Darwin wrote, "...Natural selection acts only by taking advantage of slight successive variations; she can never take a great and sudden leap, but must advance by short and sure, though slow steps." Thus, Darwin conceded that, "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down." Such a complex organ would be known as an "irreducibly complex system". An irreducibly complex system is one composed of multiple parts, all of which are necessary for the system to function. If even one part is missing, the entire system will fail to function.

However, no system has yet been discovered which has been shown to be irrducibly complex; the development of the eye for example, is wellknown and established.

Answer 3

Darwin's theory is that all living things are ruled by natural selection. Natural selection is pretty much the idea of whoever is stronger lives, and the weaker ones die. All of the higher ranking or "better" animals will live on while the rest are left to die off.

Answer 4

That trough time, a specie of animal, plant, bacteria can change.

When a life form reproduces, one of its"babies" may be different from its parents because of genetic mutation. Sometime, this mutation may give it an advantage over other individuals of its specie. (e.g.: A giraffe has a higher neck and can search food on high trees.) Because of this advantage, the life form that is different (we will call it A) can live longer and has better chances to reproduce. The life form that has not this advantage (we will call it B) will live less longer and will have less chances to reproduce. Because of that, the population of "A" will increase and the population of "B"will decrease. In the end, there will only be "A".

Answer 5

Edit : individuals in a population with traits best suited for that environment survive and increase in number -Holy122

An animal or organism that is weaker will be killed off, and the stronger will survive for longer/in greater numbers. This means that the stronger ones' genes will be passed on, and the generation is thus slightly stronger on average. This occurs in large numbers of generations, so when say 25 thousand generations have passed the organisms will be noticeably stronger, more likely to survive and more likely to procreate. So the species as a whole gets stronger by nature 'choosing' the better to be carried forward.

Answer 6

Darwin's theory of natural selection is as follows:

1. Darwin observed that population sizes of any species would increase exponentially if all its individuals born reproduced successfully.

2. However, Darwin observed that populations tend to remain the same size (except for seasonal fluctuations).

3. Darwin also noticed that resources are limited.

   • Thus, Darwin concluded that if more individuals are produced than the environment can support, then there is a struggle for existence among the population's individuals, and only some of the offspring survive each generation.

4. Darwin also observed that no two individuals are exactly alike.

   • As a result, Darwin concluded that individuals whose inherited traits give them a higher fitness (a higher probability of surviving and reproducing) and are more likely to leave more offspring than less fit individuals; survival depends on inherited traits.

   • Darwin then inferred that favorable characteristics will accumulate over generations as this unequal ability of individuals to survive and reproduce will eventually lead to a gradual change in population, especially as environmental factors filter heritable variations.

5. Furthermore, he realized that much of this variation is heritable.

Darwin's theory can also be explained as natural selection, the differential success in reproduction among individuals that vary in their heritable traits, emerges as each individual interacts with its environment. Over time, the adaptations of organisms to their environment will increase due to these reproductive differences. Then, if individuals of a particular species move into a new environment or if the environment changes, natural selection does result in adaption to [ and with ] these new conditions, while regularly & occasionally giving rise to new species.

Note that a population is the smallest unit that can evolve, natural selection can increase or decrease only heritable traits, and the favored traits depend on the environment.

Answer 7

Darwin's theory noted that all living things vary, and many of those variations are heritable. Living things tend to reproduce in greater numbers than replacement would require, so in general, not all individuals can leave successfully reproducing offspring in the next generation. If any heritable variations have an influence on reproductive success or failure, the successful variations will become more frequent in the population and the less successful ones will become less frequent. This is natural (and sexual) selection, and accounts for change (evolution) in living creatures. Evolution accounts for species transforming into different species and species splitting into multiple different species. It concludes that all living things are related by common descent.

The past tense is correct when talking about Darwin's theory of evolution because the theory has been greatly refined and expanded since Darwin's time.