pls explain darwins theory of natural selection?

Question

describe some evidence darwin used to support his theory.explain why darwins theory was not supported at the time he said them.what evidence has been obtained since darwin's own=explain usin this DNA AND GENETICS.

Answer 1

As Hugo de Vries has said, “Natural selection may explain the survival of the fittest, but it cannot explain the arrival of the fittest.”

Natural selection is a logical process that anyone can observe. We can look at the great variation in an animal kind and see the results of natural selection. For instance, wolves, coyotes, and dingoes have developed over time as a result of natural selection operating on the information in the genes of the dog kind.

But natural selection can only operate on the information already contained in the genes; it doesn’t produce new information. There are limits. For instance, you can’t breed a dog to the size of an elephant, much less turn it into an elephant.

The different dogs we see today have resulted from a rearrangement or loss of information from the original dog kind; no new information was produced. What are they? Dogs. What were they? Dogs. What will they be? Dogs. There is a big difference between subspeciation (variation within a kind) and transspeciation (change from one kind to another).

To go from that first single celled organism to a human means finding a way to generate enormous amounts of new information. You need the recipes to build eyes, nerves, skin, bones, muscles, blood, etc. Without a way to increase information, natural selection will not work as a mechanism for evolution. Evolutionists agree with this and so they point to mutations (copying errors in the genetic code) to provide the new information for natural selection to act upon. So, the question is, can mutations produce new creative information?

Dr. Lee Spetner (a highly qualified scientist who taught at John Hopkins University) said, “All point mutations that have been studied on the molecular level turn out to reduce the genetic information and not to increase it.” Did you get that? He also said, “The neo-Darwinians would like us to believe that large evolutionary changes can result from a series of small events if there are enough of them. But if these events all lose information they can’t be the steps in the kind of evolution the NDT [Neo-Darwinian theory] is supposed to explain, no matter how many mutations there are. Whoever thinks macroevolution can be made by mutations that lose information is like the merchant who lost a little money on every sale but thought he could make it up in volume.”

Dr. Warner Gitt, in answering the question (Can new information originate through mutations?) said, “...this idea is central in representations of evolution, but mutations can only cause changes in existing information. There can be no increase in information, and in general the results are injurious. New blueprints for new functions or new organs cannot arise; mutations cannot be the source of new (creative) information.”

Even the somewhat beneficial mutations they point to like antibiotic resistance in bacteria are always a rearrangement or loss of information, never a gain. For instance, a mutation that causes the pumps in its cell wall not to work in a certain way so it doesn’t suck in the antibiotics we try to kill it with. You see, it is resistant because of a loss of an ability.

This kind of stuff is used as evidence for evolution, but in every mutation (even the beneficial ones), this is always the case. Evolution requires new creative information, not a loss of information. Mutation, which evolutionists frequently hide behind, is not a magic wand that transforms living organisms into more advanced forms.

OK, what about homology? Don’t we see similarity in the anatomy and physiology of different animals? Evolutionists like to argue that these similarities prove that all life evolved from a common ancestor (common descent).

First of all, there are plenty of problems—like homologous structures that are not produced by homologous genes or the same embryological development, or homologous structures in animals that are not suppose to have a close common ancestor (no evolutionary relationship), and so forth.

But the thing is, homology can just as easily point to a common designer; it fits quite comfortably with the creation model.

As Dr. Don Batten has said, “Think about the original Porsche and a Volkswagen ‘Beetle’ cars. They both had air-cooled, flat, horizontally-opposed, 4-cylinder engines in the rear, independent rear suspension, two doors, trunk in the front, and many other similarities. Why did these two very different cars have so many similarities? Because they had the same designer!”

And as Dr. Jerry Bergman said, “...the requirements of life are similar for similar living things, and some designs are preferred in constructing animals because these designs are superior to competing designs. All automobile, bicycle and pushcart tires are round because this design is superior for the function of most tires. A tire homology does not prove common descent, but common design by engineers throughout history because of the superiority of the round structure for rolling.”

Dr. Carl Weiland said the same: “By its very nature, creation involves the intelligent application of design information, which it would seem logical to conserve. For example, if the pattern of the forelimb bones in a frog works well, following good bioengineering principles, then it would seem reasonable for the same principles to be used in the other creatures, modified to fit their particular needs.”

Answer 2

Darwin thought that one kind of animal could change into another by means of Natural Selection. If an offspring had a beneficial feature then that might result in that offspring having more offspring and the whole population eventually gaining that feature.

Darwin thought that lots of transitional fossils (in-between animals) would be found. In fact just a handful of controversial ones have been found. The fossil evidence contradicts darwin's ideas.

The science of genetics and our understanding of DNA also contradicts Darwins ideas. To evolve a new feature (a fish growing legs, say) it is necessary to increase the genetic information. The proposed mechanism is mutations. However all observed mutations are either info neutral or lossy. What we observe is natural selection with kinds, but loss of information over time - devolution.
For example lions and tigers are related and can interbreed, and are both descended from an ancestor big cat. But each has less genetic information than their ancestor.

There are lots of articles about Natural Selection here:
http://www.creationontheweb.com/content/view/3035/

Note that evolutionists often (deliberately) confuse the ideas of Natural Selection and evolution. NS is observed and is fact. Evolution (goo-to-you) is a hypothesis, which is not observed and not supported by hard evidence.

Note for example that Darwin's famous finches are showing NS, not evolution!

Answer 3

Darwin's theory suggested that those species best suited to their environment would most likely survive long enough to reproduce. If the environment changed, then the species most adapted to the change would survive and reproduce. His theory was not supported because it seemed to suggest that species evolved by Natural Selection which went against the biblical teaching of how God made the creatures during the six days of the "Creation" story. His theory was also further interpretted as suggesting that humans evolved from apes. There were many harsh cartoons in the publications of the time depicting this. Many biologists have carried out research to support his theory by looking at the development of the fertilised egg through its embryo stages and finding common pathways throughout vertebrate groups, for example.

Answer 4

First of all, let's make it clear that Darwin's theory was about natural selection, not evolution specifically. The idea of evolution had emerged on the science field prior to Darwin's trip on the Beagle and was already gaining momentum. The idea that species changed and became other species over time was already clear. What wasn't clear was 1) how it actually happened (DNA) and 2) why it happened.

Why is where Darwin came in. During his time on the Galapagos islands, he cataloged a lot of different type of Finches. He realized that these were really all the same birds that had somehow been altered to where their attributes seems to fit their environment. How is it possible for something to change to fit its environment? Well, change happens all the time. DNA is complicated and replication often produces errors, we call these mutations. Almost all of the time, the mutations do nothing or do damage. A tiny amount of the time, something beneficial happens. A bird is born with the mutation for a longer more pointy beak. On an island where this is beneficial(lots of tiny hole filled with yummy bugs) this bird does well; eating better, surviving longer to produce more offspring, which carry this long pointy beak trait on to their offspring and so on. On an island without a niche for this beak, the mutation does nothing helpful and the trait dies out. (Note: we often see this exaggerated on islands because of it's isolation from other environmental niches).

This was Darwin's theory, though it is often confused with evolution itself, it is actually the how of evolution. Things mutate. if the mutation is good, it gets carried on, sometimes to mutate even more later in time, producing other species. If the mutation give no benefit, it dies out. Only those mutations that are 'fittest' for that place, that time, that niche survive to be pass this 'fitness' on and on.... and on hundreds of millions of years.

Answer 5

Natural selection is the process by which favorable traits that are heritable become more common in successive generations of a population of reproducing organisms, and unfavorable traits that are heritable become less common (as those members of a species with more heritable characteristics are more likely to propagate and pass on gentic material). Natural selection acts on the phenotype, or the observable characteristics of an organism, such that individuals with favorable phenotypes are more likely to survive and reproduce than those with less favorable phenotypes. If these phenotypes have a genetic basis, then the genotype associated with the favorable phenotype will increase in frequency in the next generation. Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species.

Natural selection is one of the cornerstones of modern biology. The term was introduced by Charles Darwin in his groundbreaking 1859 book The Origin of Species[1] in which natural selection was described by analogy to artificial selection, a process by which individuals with traits considered desirable by human breeders are systematically favored for reproduction.

Answer 6

Natural selection is the process by which nature "selects" the organism that are most fit to survive. Let's say food is scarce, and only the fastest animals of some species can catch enough food to stay alive. The slow animals tend to die, but the fast animals tend to stay alive and continue breeding. They pass their DNA on to their offspring, so their offspring tend to have the same speedy abilities. They inherit speed from their parents. The slow parents die before they can have children, so as time goes on, there are fewer slow animals and more fast animals. The species as a whole becomes faster.

In this scenario, lack of slow-moving food is the selective pressure. Natural selection basically means "animals with certain traits die, while animals with other traits live". Humans can also impose artificial selection, such as when breeding dogs or horses for certain physical traits. It is the exact same process.

Answer 7

It can summed (very basically) up in the example of the african savannah. Lions prey on antelopes, some of these antelopes have random mutations which mean they have longer legs, meaning they can run faster than other antelope and, more importantly, faster than the lion. The slower antelope are more likley to get caught and killed, so thier genetic material cannot be passed on as effectively. The faster antelope are more likley to survive and pass on thier genetic material (including the mutation) as they breed. Making more fast antelope, who again will more likely survive and reproduce, passing the mutation on again. Obviously, as time passes enough of these "mutants" have developed to create a colony of fast antelope and the mutant gene is "normalised".
That's a basic summary, there would be lots of these mutations over time, some would be successful. others would not.

Answer 8

Evidence- the variety of the same species ofbird in the Galapogas Islands.
It was not supported as there was no scientific evidence, only observations, and every one was Christian.
New evidence- we can use fossils to see how animals have developed. Horses are a good one.

Answer 9

its simple.
the organisms evolve due to the environment persisting around them.
there is struggle for mate food and shelter, the fittest survives in the nature.
for this the organisms undergo adaptations.

main study he made was in galapagos,he studied about finches and their evolution according to their need for all the things

he never mentioned DNA and genetics in his theory as they were not discovered at that time.

his theory was rejected because people believed on other theories like lamark's theory which explained that organ which is put into more use evolves in size and shape
read the third chapter of class XI(old version)

Answer 10

Darwin observed the relationship of plants and animals all over the world, whilst he was on the Voyage of the Beagle. He observed organisms on islands off the coast of South America and those on the mainland. These observations showed that they were related but not identical. This led Darwin into believing that over time things must adapt to suit their environment.

Darwin decided it was possible for species to change from one form and develop into another over time. This led him to the notion that all life forms were not fixed but continuously changing or evolving. The other part of the theory was that living things weren’t the result of many separate creations (as had been suggested in Genesis) but of long, intertwining biological histories. His general idea was that amongst a family of plants or animals individual members carried hereditary traits. These traits would be general to the individual’s family, but not the species. It is these traits which could give the member a better chance of survival and reproduction. This is what Darwin called Survival of the Fittest or Natural Selection. Those individuals with slightly better adaptations, according to the theory, would get more food, be healthier, live longer and, most importantly, have more mates. As time progresses, traits become more obvious, therefore later generations will be more defined and, possibly after thousands of generations, form a new species.

An example of this theory can be seen in the Galápagos Islands. The Galápagaos are 16 islands off the coast of South America that Charles observed in 1835. These islands, we now know, were formed 4 million years ago from volcanic activity and had no life on them. Therefore, any animal living there now must have either flown or drifted to the islands. One species thriving in the Galapagos is the Marine Iguana, the only sea going Iguana (a type of lizard) in the world. So, if it is known that the Galápagos were initially empty, “Where did this Iguana come from?” Darwin asked. Other reptiles came to the Galapagos Islands like the Yellow Land Iguana from South America. Reptiles such as these, being able to survive for long periods of time without food or water, could have drifted to the Galápagos on driftwood or bark. Suppose the land Iguana had no food, due to overpopulation, and was forced to feed in the shallow waters on seaweed, small fish and molluscs. If one Iguana could swim better and could hold onto rocks better than others, even slightly, it would get more food and become stronger and healthier. It would therefore win more mates and reproduce more whilst its other brothers and sisters die from starvation. Later generations from this Iguana inherit and refine this talent and will survive and reproduce. Now, there are more of these skilled Iguanas who can also gather food from the sea. Thousands of generations later, with these traits selected, we end up with a new species, the Marine Iguana, which now far outnumbers the Land Iguana.

This is only a suggestion of how the Marine Iguana has evolved, but if Darwin’s "Origin of Species" stands, it is a realistic one.

As you can see, there are two vital steps to Darwin’s theory the first of which is heredity.

Darwin’s Theory depends on traits and characteristics being passed along from parent to child, that is, between generations. Evolution couldn’t take place without this process, which is called heredity.

Gregor Mendel (1822-1884) was an Austrian monk who discovered the basic rules of heredity by experimenting with pea plants. He studied characteristics such as the colour of the flowers, height variation and the texture of the seeds. From this he studied inheritance, the process of passing characteristics to the next generation of plant, and he came to several conclusions –

1. The characteristics of an organism are passed along from parent to child by pieces of information called genes. Every gene represents a single bit of information containing one characteristic.
2. Alleles are two or more genes that carry a piece of information about a single characteristic, for example: one of the allele pair may be for blue eyes and the other may be for brown. Alleles are usually found in pairs, one of which is dominant, or over powering, and one recessive which is masked by the dominant.
3. In reproduction each gamete, or reproductive cell, (sperm or egg), has only one of the pair present.
4. If a dominant and a recessive allele are both present, the individual will be affected by the dominant allele.

Mendel’s observations were later shown to apply also to animals by the American scientist T H Morgan.

This idea can be investigated by examining the human trait of being able to roll the tongue. If the correct heredity gene is found in a human, the muscle which enables the tongue to be rolled is produced. Before reproduction, sex cells are created through the process of meiosis. These cells will contain either of two genes for tongue rolling, one that produces the muscle or one that doesn’t. In reproduction, each parent will provide one of these genes to the child. In humans the “rolling gene” is dominant; therefore, if a “rolling gene” is present the child will have the ability to roll his or her tongue. There are three possible outcomes:

1. two “rolling genes” are present and the offspring develops the muscle. Subsequently, all the offspring’s children will have the ability.
2. one of each gene is present. Because the rolling gene is dominant, the muscle will develop. They will have 1/2 rolling and 1/2 non-rolling gametes.
3. two non-rolling genes are present. The muscle therefore can not be developed. Only recessive genes will be passed to offspring.

The tongue rolling gene is passed along generations; therefore, it is a hereditary trait.

Although Darwin didn’t know of Mendel’s discoveries, Darwin applies some of these ideas by suggesting that inherited traits can give individuals a better chance of survival, which is shown in Natural Selection.

The second important basis of Darwin’s theory is a process called Natural Selection. Selection is the most important factor in evolution and provides the step of choosing the organism best adapted to its environment. Darwin’s idea was that hereditary traits provide individuals with a greater chance of survival and reproduction.

Darwin also proposed that there were different types of selection. The most controversial he proposed was sex selection. This states that females, perhaps having more practical bodies, have a greater advantage over males with their more awkward bodies, in some populations. An example of this type of selection is the male peacock. His tail is oversized and brightly coloured. The female, on the other hand, is plain coloured and small tailed. The male’s tail is used to attract the female for mating, though often it attracts predators also. His large tail also hinders his escape and often he ends up as dinner.

Stabilising selection is always occurring in every population. It kills off individuals with excessive abnormalities or mutations. Many of these mutants die either before birth or immediately after birth.

Disruptive selection is a process that causes the increase of mutants in a population.

Directional Selection is a process that increases the number of individuals with an extreme observable characteristic. It usually results in the gradual replacement of genes within a genepool. (A genepool is made up of all the alleles of all the genes of every individual in the species).

Frequency-Dependent Selection decreases the occurrence of common characteristics and increases the uncommon ones.

Natural Selection gives individuals with an advantageous trait a better chance to reproduce and further their genetic line. Over time a stronger population is produced and unreliable characteristics are lost.

Over the years more research has furthered Darwin’s theory and has added a few of the mentioned forms of selection. Many other theories and ideas have also been developed from Darwin’s theory.

hope that helps..... now do your homework!!!