The Evolution Site
The theory of natural selection as the underlying principle of evolution is the defining factor in the field of modern biology. It ties together disciplines that are as diverse as genetics microbiology, and Palaeontology.
However, the study of evolution is often controversial, and the resulting misinformation can confuse people about its basic concepts. This site can help to clarify the fundamental concepts.
What is Evolution?
Modern evolutionary theory focuses on the gradual and cumulative changes that take place in populations over time. These changes are caused by natural selection, which increases the amount of organisms that possess beneficial traits that allow them to survive and reproduce in a particular environment. As a result, these organisms have more offspring than those that don't have these beneficial traits. This results in the genetic changes that can eventually lead to the creation of new species.
The term "evolution" is often ascribed to the notion of "survival of the fittest" which implies that people who are the most adapted to a specific set of environmental conditions will have an advantage over those who aren't well-adapted. This is just one of many ways that evolution can happen.
Another common way the word evolution is used to suggest that a species will eventually move from one state to the next state of being. This type of view of evolution could be described as anagenetic or cladogenesis. This theory is not supported by the definition of evolution that is scientifically accepted. Instead, the scientific theory of evolution concentrates on the changes that happen in populations over time and these changes are caused by genetic mutations and natural selection.
Some scientists, such as the great Charles Darwin, advocated this theory of evolution. Others, notably Alfred Russel Wallace, who created the macroevolution theory and believed that this was the only way that the higher forms of life could have evolved from the lower forms.
To be able to be considered a theory, it must be capable of surviving rigorous testing and evidence. The evidence for evolution has stood the test of time and has been backed by numerous studies in a wide range of sciences, from geology to biology to astronomy. In reality evolution is regarded as one of the fundamental tenets of science today and is supported by the vast majority of scientists across the globe. However, there are many misconceptions about the nature of the theory of evolution, particularly the relationship it has with religion.
What is the Theory of Evolution (Evolutionary Theory)?
Evolution is the scientific explanation for the way living things change over time. It relies on a number of well-established observable facts: that more offspring are created than are likely to survive in the long run; that individuals differ from one another in their physical characteristics (phenotype); that different characteristics result in different rates of reproduction and survival and reproduction; and that these traits can be passed on to the next generation. These observations are supported by a growing body of evidence derived from molecular biology, palaeontology and climatology functional morphology geology.
The theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the late 19th century to provide an explanation for how organisms adapt to their biological and physical environment. It is the most widely accepted and tested theory in the field of science. Its predictions have been proved out by the fact that, for instance, more complex organisms have less genetic mutations than simpler ones. The more successful an organism is in terms of survival and reproducing, the more likely it will transmit its genes to the next generation.
Some people oppose evolution because they believe that it implies there is no purpose for life. However, a lot of scientists who are also religious such as the renowned Cambridge Palaeontologist Simon Conway Morris, believe that evolution isn't just compatible with faith in God but also enhances it (BioLogos 2014).
Many highly skilled evolutionary biologists have been involved in the development and testing the theory of evolution, including several revered evangelical Christian leaders. Many of them have contributed to the understanding of a wide variety of phenomena, including phylogenetics and genomics and the formation and function of fossils.
The term "theory" is sometimes used incorrectly to mean a guess or speculation but in reality it refers to a scientific idea that has been systematically developed and tested over time. Scientists test hypotheses through repeating the experiments or observations that led them to the conclusion. Thus, the theory of evolution has been repeatedly borne out, as have the related theories of Copernican, germ and atomic theory.
What is the Process of Evolution?
The process of evolution is a gradual shift in the genetic makeup of different individuals within a species over time. This change is a result of natural selection, which favors individuals who are better adapted for their environment. The people who are more adaptable have better chances of reproduction and survival. As more people survive and reproduce, their genes become more prevalent in the general population. This process is sometimes referred to as "survival of the strongest."
According to original site of evolution the mutations that result in genomic variation are the raw basis for evolutionary change. These mutations may occur at random or under the influence of the environment. If mutations occur in a random manner, the allele frequencies may vary from generation to generation. When a mutation is beneficial it can increase the frequency of the allele, causing the allele to be spread across the population.
The changes in frequency of alleles can lead to new species over time. The new species will develop and evolve into new forms. This is a process called macroevolution. The formation of a new species is usually caused by changes in the environment which provide certain types of resources available or cause new environmental problems. The evolution of finches in Galapagos Islands, for example, is due to the availability of new foods and the need to defend themselves against predators.
In a larger sense the term "evolution" refers to any change that occurs in the traits of organisms over the course of time. This change can be small, such as the development of a new coloration, or even massive, like the creation of a new organ.
Scientists who accept the theory of evolution generally agree on the importance of genetic change in generating evolution. They also agree that the process of evolution occurs over a lengthy period of time, typically millions of years. However, they differ on the importance of different factors in accelerating or retarding the process, like the impact of environmental pressures, sexual selection and mutation bias. Despite these differences scientists believe that evolution has occurred and that the evidence for this is overwhelming.
What evidence can be found for evolution?
Since Darwin's time, scientists have collected evidence that supports Darwin's theory of evolution. This evidence comes from fossils that show the evolution of living organisms over time. Similarities between living organisms as well as embryology, biogeography and genetics are further evidence.
The evolutionary tree is the most effective way to prove evolution. It demonstrates how species are closely related. Another evidence source is homologous structures, which have a similar structure in different species, but serve different purposes such as the wings of birds and bats. The fact that different species evolve and adapt to the same environment is also evidence of evolution. For instance, arctic foxes and Ptarmigans have white pelts during the winter months which blend with snow and ice. This is a type of convergent evolutionary process, which suggests that the species share common ancestors.
The vestiges of structures are another source of evidence. They are the remains of an organism that may serve a function in the past. The human appendix for instance, is a vestige from an organ that once used to digest food. These structures tend to shrink in size once they are no longer utilized, a process known as natural selection.
Scientists have also gathered evidence for evolution by observing and testing. Evidence for evolution is divided into six categories: directly visible small-scale changes in biogeographic distribution, comparative anatomy, the fossil record, genetics, and classification. Each of these categories offers compelling evidence for the evolution of life.
Although many people have misconceptions about the theory of evolution it is a scientific fact. It is not just a theory; it is a potent collection of decades of research and observation that has been tested and proven. Scientists continue to collect and study new information to better understand the evolution of Earth's evolution regardless of whether people believe in the theory of evolution or not. This information will aid scientists understand how to prevent future global catastrophes and how to best utilize the resources of our planet. This will allow us to better serve the needs of people on this planet.