Charles Darwin had two great themes in "On the Origin of Species" which accounted for the similarities and adaptations
characteristic of living organisms. To account for the adaptations of organisms and those innumerable features that equip
them for survival and reproduction, Darwin (and Wallace) independently came up with the central theory of evolutionary
process: natural selection. Natural selection gives insight in to why organisms are the way that they are. Adaptations are
phenotypic variants that result in the highest fitness among a specified set of variants in a given environment. In reference
to humans, there are many traits that have been selected and adapted for throughout their evolutionary history giving them
the characteristics that they have today. In this paper I will discuss some parts of the human body, which have been found
to be selected for by the evolutionary mechanisms of natural selection, adaptation and mutation.
Natural selection, adaptation, and mutations are three components of the evolutionary process, each one having either
positive or negative effects on the other. What exactly is natural selection? There are many variations of the definition but
most agree that it must include the following concepts: some attribute or trait must vary among biological entities, and there
must be a consistent relationship, within a defined context, between the trait and one or more components of reproductive
success, where "reproductive success" includes both survival and the reproductive processes themselves (Futuyma, 1998).
Charles Darwin's theory of natural selection states "if variations useful to any organic being ever occur, assuredly
individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong
principle of inheritance, these will tend to produce offspring similarly characterized." Regardless of how it is defined,
natural selection and its action can have tremendous effects on the members of a population. It is natural selection that
causes adaptation, and these adaptations evolve to ensure the survival of a species.
Evolution, in a very broad sense, is defined as descent with modification and often with diversification (Futuyma, 1998).
Darwin's idea of evolution was that it occurred by descent with modificatio...
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...-carbohydrate, high protein
diet. Certain metabolic adaptations were therefore necessary to accommodate the low glucose intake. Many indicate that
the adaptive response to the low carbohydrate intake is insulin resistance(Miller, Colagiuri, 1994).
A study done by J.C. Brand Miller and S. Colagirui proposes that insulin resistance offered a survival and
reproductive advantage during the Ice Ages. This study also proposed that a carnivorous diet would have disadvantaged
reproduction in insulin-sensitive individuals and positively selected for individuals with insulin resistance. Another factor
mentioned was the various environmental factors that contributed to the low carbohydrate intake such as the types of
foods that were available.
The forces of natural selection on the evolutionary processes in humans can have a broad range of effects on the
characteristics of humans. There are no concrete answers to some of the questions proposed in this paper, but time will
soon tell exactly how the evolutionary mechanisms have effected the human race. The human species will continue to
evolve as long as the mechanisms of evolution and environmental factors act upon us.
Natural selection, or the ability of species to adapt to the dangers of their environment to work towards the goal of reproducing and surviving.
Darwin describes natural selection as “a description of what happens when variations occur in a population where resources are limited. The individual animal or plant that has certain change in its genetic make-up will survive natural (4)” For example, in a population where more individuals are born into a harsh environment that can’t sustain them all, those individuals that have expedient variations within their DNA will have a higher chance of surviving. This is called natural selection. When
Charles Darwin founded the theory of evolution by natural selection, which according to this principle defines; biological characteristics enhance survival increase in frequency from generation to generation (Larsen et al. 22). These individuals are inclined to produce more sustainable offspring to pass their genes to, meaning that some individuals are more reproductively fruitful than others. Natural selection requires variation in a species, which can result by gene flow, mutation, or genetic drift & also involves environmental stresses such as climate change. These result as the evolutionary means of how certain traits can be selected. Eventually, traits that give individuals certain advantages, such as bipedalism in hominids, will be selected in great numbers & more individuals in a population will display these traits.
There were only two faults that he found within her – theater and false jewelry. Lantin didn’t share her love for theater. After attending many performances with her, he finally begged her to go with some lady friends. Her love of theater brought about her love of fake jewelry. Sometimes she would bring out her jewelry in the evenings just to look at them. The theater and jewelry didn’t seem to be affecting them financially in anyway, so why not let her indulge herself in them. She was happy and he was happy.
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.
Charles Darwin’s theory was natural selection, the survival of the fittest and the struggle for existence, which had a great impact on selective breeding. Organisms that were well-adapted to their environment had more tendency to survive and reproduce, providing their genetic characteristics for future generations whilst those less-adapted organisms were more likely to be decreased in amount. Charles Darwin’s theory also established that all species of life were related and had descended over time from common ancestors.
Natural selection is one of the most incredible feats of nature. Through this process, the traits of a species that are best suited for its environment become dominant in the species. Since the beginning of time, people have questioned why animals seem to be so well suited to their environment. Many people quickly assumed the seemingly perfect animals must be a result of some intelligent design. However, these people did not consider that the characteristics of these species could have occurred naturally. Natural selection occurs when organisms with more desirable characteristics survive to maturity and
Evolution is the theory that all living forms came from ancient ancestors and is the natural process to improve a species chance of survival. Through a series of mutations, genetic drift, migration, and natural selection today’s descendants show an amazing amount of similarities and diversity. Evolution on a small scale is called microevolution, an example being the
Convergent evolution is the process in which organisms which are not closely related derive akin traits separately due to the need for adaptation to similar environments or ecological niches. According to the neo-Darwinian view, species with similar environmental living settings experience similar selection pressures. Natural selection then acts on the arbitrary changes or current genetic variability leading to identical phenotypic solutions. There may be resemblances at a phylogenetic level, but the basic DNA sequences are different. Convergent evolution gives rise to characteristics which are referred to as “analogous structures”. They are often contradicted with “homologous structures” which have the same ancestors. Convergent evolution
Natural selection was one of the most important discoveries in the Nineteenth century, and it has changed peoples’ position ever since. Natural selection also provides people a new chance to find truth in the world. Even though it has been demonstrated for over one hundred years, we can still try to find new information from it. Today, natural selection is a very important subject that a lot of scientists try to use to explain different kinds of evolutionary questions.
Environmental conditions have stimulated the important developments of how we became who we are today. The development of early humans faced environmental changes and evolved bigger bodies, larger, more complex brains. With having a bigger more complex brain came as an advantaged. Processing and storing a lot of information became easier, it gave early humans the advantage to interact more socially and to become aware with encounters to unfamiliar habitat (Bigger Brains: Complex Brains for a Complex World, 2015).
In 1859, Charles Darwin set out his exploration of the evolution by natural selection as an explanation for adaptation and speciation 1859. Darwin characterized natural selection as the rule by which each variety of a trait, if valuable, is safeguarded. Another researcher, Alfred Russell Wallace, came to a similar conclusion, but because Darwin was well-known and respected researcher even before he composed On the Origin of Species, Wallace was obscure and unknown, so individuals were more likely to listen to Darwin. Darwin's theory comprised of two key emphases which were varied gatherings of creatures advance from one or a couple of basic predecessors of adaptation. And the component by which this development happens is natural selection.
Natural selection: It is defined as the process of natural adaptation to the environment by the species to survive and their existence through the production of offspring.
Natural selection is not a fully random process that functions by ‘chance.’ As natural selection
2) Natural selection- the process whereby the natural factors of environmental resistance tend to eliminate those members of the population that are least well adapted to cope and thus, in effect select those best adapted for survival and reproduction.