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Theory of evolution
Strengths and weaknesses of the evolutionary theory
Genetic drift and evolution
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What is evolution and how does it work? Evolution is the theory of how one form of life changes into another form. Evolution also is the change of a population’s inherited traits from generation to generation. Evolution helps to explain why an animal, human, and plant looks the way it does and acts the way it does; it gives an explanation of the history of life. Genes come in many varieties and the evolution helps to make it happen. Mutation, natural selection, genetic drift, and gene flow: the four forces that make the evolution work.
Mutation happens when the DNA gene gets changed, moves, or is damaged. When this happens it causes the genetic message to be carried by that gene to be different. This process can occur in somatic cells. The somatic cells are all the cells that are a living organism except the reproductive cells, meaning the body. For example, the skin cells on your legs are and will not be passed on to ones offsprings. In addition those leg cells will not effect the evolution. Another occurrence is called gametic mutations, which is in a woman's eggs and or in a man's sperm. These are cells that are and can be passed on to ones offsprings, and they are the essentials for the evolution. There are three effects mutation causes to a species. Species can only takes on one of the three. The three effects are bad, neutral, and good. Having a bad mutation can cause one to have a harder time being able to survive. Having a neutral mutation will not change or help one to survive. Having a good mutation will help one to survive and have a better chance of survival. However, mutation is random in the evolution, and provides raw material for natural selection, genetic drift, and gene flow...
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...he genetic differences making more of a variation but it does this process slowly.
Evolution is a on going process and the evolution is made up of many different processes. It allows species to become what they are, how they act, and what they will become. It also allows species to be able to survive. It produces new and different species through ancestral populations of organisms and moves them to new population. Both natural selection and genetic drift decrease genetic variation. If they were the only mechanisms of evolution, populations would eventually become homogeneous and further evolution would be impossible. There are, however, mechanisms that replace variation depleted by selection and drift (Colby).
Work Cited
Colby, Chris. "An Introduction to Evolutionary Biology" Web. 28 August 2015.
http://www.skepticfiles.org/evolut/evolutfa.htm
Evolution, also known as descent with modification, is a phrase Darwin used in proposing the evolution of Earth’s many species. Charles Darwin noticed that the descendants of ancestral species were different from the present day forms of species. Darwinism is a theory of biological evolution developed by Charles Darwin who was an English naturalist. He expounded the theory of evolution in his book of the Origin Species in 1859. He expresses that all types of organisms emerge and develop through natural selection, small, acquired traits that expands the individuals of capacity, survival, and reproduction. In this book, Darwin theorized that animals and plants evolve and develop with the aid of the creator through the process of natural selection.
Biological evolution is a change in the characteristics of living organisms over generations (Scott, 2017). A basic mechanism of evolution, the genetic drift, and mutation is natural selection. According to Darwin's theory of evolution, natural selection is a process in nature in which only the organisms best adapted to their environmental surroundings have a higher chance of surviving and transmitting their genetic characters in increasing numbers to succeeding generations while those less adapted tend to be eliminated. There has been many experimental research projects that relate to the topic of natural selection and evolution.
Natural selection is associated with the phrase “survival of the fittest.” This basically means that the fittest individuals can not only survive, but are also able to leave the most offspring. The selection of phenotypes affects the genotypes. For example, if tall pea plants are favored in the environment, then the tall pea plants would leave more offspring behind, meaning that the offspring will carry tall alleles. Phenotypes that are successful have the best adaptations (characteristics that help an individual to survive and reproduce) to their environment. These adaptation arise from the interactions with living and nonliving aspects of the environment. Some nonliving aspects of the environment are climate, water availability, and concentration of mineral sin the
What is evolution? Evolution in modern terms is fairly easy to understand. Evolution is the theory that life on earth began with a single celled organism that lived more that 3.5 billion years ago that slowly evolved into many diverse creatures over time. When you break down this theory into sections you get 6 factors: evolution, gradualism, speciation, common ancestry, natural selection and nonselective mechanisms of evolutionary change.
Evolution in general, is a hard concept to grasp. There are multiple factors that effect the outcome a species, for example: genetics, nurture, nature, and the environment all play an important role. It was once said that species do not survive due to the fact that they are the strongest or the most intelligent, but because that species is the most responsive to change.
What is evolution? Evolution is the process at which all living things that are around use today that have ancient ancestors in their background. Also, with evolution it allows for use to see how we have similarities as well as differences from all living organisms from the past to the present. By being able to see the similarities as well as differences it shows how overtime we have changed and evolved through the use of evolution. However, the use of evolution involves different mechanisms in order for it to take place.
According to Darwin and his theory on evolution, organisms are presented with nature’s challenge of environmental change. Those that possess the characteristics of adapting to such challenges are successful in leaving their genes behind and ensuring that their lineage will continue. It is natural selection, where nature can perform tiny to mass sporadic experiments on its organisms, and the results can be interesting from extinction to significant changes within a species.
Natural selection is simple yet complex process that allows species adapt to its environment. Natural selection guides evolution by “sifting out” favorable traits that increase survival for the species. Natural selection is driven by reproductive success. If a species can reproduce and its offspring survive than any traits in its genotype that assisted in its survival will be passed on from generation to generation and ensure that the species will live on. Around the time the Theory of Evolution was suggested, society was very religious and very pressed on the Theory of Creation, so the publication of Darwin’s The Origin of Species by Means of Natural Selection caused a lot of controversy. Darwin gave the world strong evidence that natural selection and evolution played a major role in the development of the species that we see today. Of course natural selection is not the only process driving evolution. In order for natural selection to happen, the species has to have genetic variation. Genetic variation happens because of mutations and recombination of genes. Other processes that contribute are gene flow and genetic
Evolution is the heart of life. Without it, life could not be sustainable. When the environment changes and the species within the environment fails to adapt or change, then all living organisms would perish over time. Charles Darwin, a biologist and naturalist, is known worldwide for his contributions to science for the extensive research and experiments conducted to help support the theory of evolution and how it worked. One basic mechanism that can be used to understand evolution is natural selection. “Resources are limited in nature, organisms with heritable traits that favor survival and reproduction will tend to leave more offspring than their peers, causing the traits to increase in frequency over generations.” (Darwin, Evolution,
...generations. If it is a beneficial mutation, then it will likely not only pass on through reproduction, but those offspring will have better odds of reproducing in order to “spread” that trait onto future offspring. This is the process of natural selection. If there are enough changes or the change is drastic enough, a new species can evolve. So, evolution comes about as a result of changes to DNA and some of those changes to DNA can come from external factors such as environment, climate, and culture.
The evolutionary theory is the concept that species evolve over time through the mechanism of natural selection of survival and reproduction. Natural selection means acting on the assumption that various living organisms were produced by genetic diversity and mutation. The evolution theory may also be referred to as the philosophizing science. This theory states that all phenomena are derived from natural causes and can be explained by scientific laws without reference to a plan or purpose.
Many scientists in the past, such as Aristotle and Plato, believed that there were no changes in populations; however, other scientists, such as Darwin and Wallace, arose and argued that species inherit heritable traits from common ancestors and environmental forces drives out certain heritable traits that makes the species better suited to survive or be more “fit” for that environment. Therefore, species do change over a period of time and they were able to support their theory by showing that evolution does occur. There were four basic mechanisms of evolution in their theory: mutation, migration, genetic drift, and natural selection. Natural selection is the gradual process by which heritable traits that makes it more likely for an organism to survive and successfully reproduce increases, whereas there is a decline in those who do have those beneficial heritable traits (Natural Selection). For example, there is a decrease in rain which causes a drought in the finches’ environment. The seeds in the finches’ environment would not be soft enough for the smaller and weaker beak finches to break; therefore, they cannot compete with the larger and stronger beak finches for food. The larger and stronger beak finches has a heritable trait that helps them survive and reproduce better than others for that particular environment which makes them categorized under natural selection (Freeman, 2002).
Most species weed out detrimental genetic mutations by natural selection. In other words, only the fittest survive long enough to reproduce. Then the offspring, of course, carry the supposedly stronger traits forward. However, in humans, the weak have been prevented from dying out.
1)Gene Flow. Gene flow is the result of a new population being added or mixed with an existing population. When a new population comes in, it brings with it various new alleleles. When these two populations breed, the alleles from the new population mixes in with the old. This can be either random or non random
Natural selection is based on the concept “survival of the fittest” where the most favourable individual best suited in the environment survive and pass on their genes for the next generation. Those individual who are less suited to the environment will die.