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An essay under natural selection in evolution
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Natural selection is the evolutionary change within a species. Variation within a generation of a species can increase the chance of survival and producing offspring. With time each generation will receive these adaptive traits and evolution by natural selection will occur. Given that there is variation in the population, and that, variation is inheritable, if enough of those adaptations were accumulated, a new species could arise.
Any structural, behavioural or physiological characteristic which is inherited, that allows the species to be better suited to its environment, is an ‘adaptation’. In any sexually reproducing organism population, there will always be a large variation in the inherited characteristics. Changes in the environment,
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“…reflecting on the mutual affinities of organic beings, on their embryological relations, their geographical distribution, geological succession, and other such facts, might come to the conclusion that each species had not been independently created, but had descended, like varieties, from other species.” (Charles Darwin. The Origin of Species)
Evidence for natural selection
Darwin 's theory of evolution by natural selection is one of the best substantiated theories in the history of science, supported by evidence found in studies of Palaeontology, biogeography, Comparative embryology, comparative anatomy and biochemistry.
Palaeontology is the study of fossils. Fossils are the remains or traces of long dead animals and plants that become trapped in sediment, ice or amber which allows them to be preserved. They provide evidence of how living things have evolved over time on earth.
Two aspects of the fossil record are most important for supporting evolutionary ideas;
Older fossils found to contain simple life forms, whereas younger fossils contain much more complex forms of
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.
Some research has reported finding insects fossilized in amber, containing species such as a termite (30 million years ago), and a weevil from approximately 130 million years ago. These are extraordinary findings, but of course disputed. ...
Natural selection is a theory suggesting that some genetic traits will be more common than another trait in a given environment in which the organisms live in. Natural selection is a slow and gradual process which will happen in the matter of generations of the species. The traits become less or more common depending on the environmental circumstances, in other words, selection pressure.
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
Anyone with even a moderate background in science has heard of Charles Darwin and his theory of evolution. Since the publishing of his book On the Origin of Species by Means of Natural Selection in 1859, Darwin’s ideas have been debated by everyone from scientists to theologians to ordinary lay-people. Today, though there is still severe opposition, evolution is regarded as fact by most of the scientific community and Darwin’s book remains one of the most influential ever written.
Species that now populate the Earth come from other species that existed in the past, through a process of descent with modification. Biological evolution is the historical process of transformation from one species in other descendant species, including the extinction of most of the species that have ever existed. One of the most romantic ideas in the evolution of life is that any two living organisms, different as they are, they share a common ancestor sometime in the past. We and any current chimpanzee share an ancestor of 5 million years. We also have a common ancestor with any bacteria that exist today, although time this predecessor to soar in this case more than 3000 million years. However, the idea of evolution by itself is an open concept, is a mechanical description of change does not say anything about the engine or the creative force behind the transformation. Thus, in principle, evolution can be driven by immanent laws of matter, or a divine creator or by blind forces,
Charles Darwin’s theory of natural selection explains the general laws by which any given species transforms into other varieties and species. Darwin extends the application of his theory to the entire hierarchy of classification and states that all forms of life have descended from one incredibly remote ancestor. The process of natural selection entails the divergence of character of specific varieties and the subsequent classification of once-related living forms as distinct entities on one or many levels of classification. The process occurs as a species varies slightly over the course of numerous generations. Through inheritance, natural selection preserves each variation that proves advantageous to that species in its present circumstances of living, which include its interaction with closely related species in the “struggle for existence” (Darwin 62).
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
Darwinism, the theory of evolution, is a controversial theory that is still being contemplated today. Before the 19th century scientist were puzzled by the idea of where humans, plants, and animals originated. In the late 1700s the question was first tried by a group of scientist, but they were not successful. It was not until a young Charles Darwin found interest in the subject that the discovery was finally able to become a theory. His observations led to his theory of evolution by natural selection. Although, it was a new discovery that shocked so many, Darwin and his accomplices did not realize how significant their newfound theory was. ~~~~
Only in the past one hundred years have men finally put aside their Biblical and mythical tales about creation, and looked to the facts in order to piece together a logical explanation for the origin of mankind. In turn, men were now able to explain the enigma of their origin without the presence of a supernatural being responsible for their creation. At the head of a slew of men trying to uncover logical reasons for mans derivation was Charles Darwin. Darwin was the most accomplished of these men because he was able to put forth a logical conjecture that was based upon facts and observations. This theory, for a short time, was able to end the feud among educated men because many now put their trust in this new “theory of evolution”. Unfortunately, this revolutionary new theory threatened the religious beliefs about creation and soon a new rivalry emerged between the creationists and evolutionists.
With its abundance of genera, the Burgess Shale is one of the world’s most important fossil fields. It’s discovery in 1909 led to over 100 years of paleontological study in the Canadian Rockies, a majority of which has been carried out in two quarries known as the Walcott and Raymond quarries (Hagadorn, 2002). Though he was originally in search of trilobites in the Burgess Shale Formation, paleontologist Charles Walcott also discovered a diverse group of soft- and hard-bodied fossils, from algae and sponges to chordates and cirripeds (Hagadorn, 2002). Soft-bodied fossils are incredibly rare due to their delicate structure and susceptibility to decay, so it is hard-bodied fossils that more regularly occur in fossil findings. However over 75,000 soft-bodied specimens have been found in the Burgess Shale formation (Hagadorn, 2002). These specimens are preserved in layers of shale formed from deposits of fine mud. One of the most significant species discovered is the Pikaia gracilens. Believed to be an early chordate, the Pikaia gracilens existed very close to the beginning of the evolutionary path that ultimately lead to humans (McGraw-Hill Encyclopedia, 2006).
Charles Darwin in his book, On the Origin of Species, presents us with a theory of natural selection. This theory is his attempt at an explanation on how the world and its' species came to be the way that we know them now. Darwin writes on how through a process of millions of years, through the effects of man and the effects of nature, species have had an ongoing trial and error experiment. It is through these trials that the natural world has developed beneficial anomalies that at times seem too great to be the work of chance.
...of ancient prokaryotes into eukaryotic cells which gives rise to the present-day model of life is wondrous enough, but the fact that the organelles work in such efficient harmony, seemingly directed like well crafted machinery is another ponderous development. The layout of life begins with the cell. Without it there is no life even on a microscopic level. To imagine that giant beasts of the Jurassic and Triassic periods such Triceratops and Liopleurodon being sharing the same base parts as some as infinitesimally small as an amoeba or a plankton is astonishing. What's more amazing though is the fact it is readily provable and verifiable. In the study of life, the make up of all creature is known at a basic level. Even without the the scientists to explain the facts, the facts themselves are immutable in terms of defining the make up and rules of existence of life.
Charles Darwin, the English naturalist and geologist is attributed and accredited for his theory of evolution. His theory of evolution is based on the premise that strong heritable traits help individuals to survive in adverse and inimical environments.
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.