The Evolution Site
The concept of natural selection as the basis of evolution is the central force in the field of modern biology. It ties together disciplines that are as diverse as genetics microbiology, and palaeontology.
The study of evolution can be controversial and the misinformation that results can cause confusion about its fundamentals. This site explains 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 the result of natural selection. This is a process which increases the number of organisms that have beneficial traits, which enable them to live and reproduce in particular environments. As a result, these organisms have more offspring than those who do not have the beneficial traits. This leads to a genetic change that can eventually lead to the development of new species.
The term "evolution", is often associated with "survival-of-the best" which implies that people who are more adapted to certain environmental conditions will have an advantage over those who are less well adapted. In actuality it is only one of the many ways that evolution can occur.
Another popular way to use the word evolution is to suggest that a species are able to move from one stage to the next. This theory of evolution is called anagenetic or cladogenesis. The scientific definition of evolution does not support this view. Instead the scientific theory of evolution concentrates on the changes that take place within 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. Alfred Russel Wallace who developed the macroevolution theory believed that this was only way the higher living forms could have evolved.
A concept must be able stand up to rigorous tests and evidence in order to be considered as a theory. Evolution has stood the test of time, and has been supported in numerous scientific disciplines ranging from geology to biology, from astronomy to chemistry. In reality evolution is regarded as one of the fundamental tenets of science today, and is backed by the vast majority of scientists worldwide. However, many people have misconceptions about the nature of the theory of evolution, particularly how it relates to religion.
What is the Theory of Evolution?
Evolution is a scientific explanation of how living things change with time. It is based on a range of well-established observable facts: that more offspring are often produced than can possibly survive and that individuals differ from one another in their physical characteristics (phenotype); that different traits have different rates of reproduction and survival and can be passed down to the next generation. These findings are backed by a growing amount of evidence from molecular biology, palaeontology climatology functional geology, morphology.
Charles Darwin and Alfred Russel Wallace independently developed the theory of evolution by selection in the mid-19th century as a way to explain how organisms are able to adapt to their physical and biological environments. It is today the most supported and most extensively tested theory in all of science. Its predictions were proven by the evidence, for example that more complex organisms have less genetic mutations. In addition, the more successful an organism is at reproduction and survival in its ability to reproduce, the more likely it will be to pass on its genes to the next generation.
Some people oppose evolution because they think it suggests that there is no purpose to life. Many scientists who are religious like Cambridge palaeontologist Simon Conway Morris (BioLogos, 2014), believe that evolution is compatible with faith in God and is even enhanced by it.
In reality, a large number of highly qualified evolutionary biologists, including a few who are renowned evangelical Christian leaders are involved in the creation and testing of the theory of evolution. Many of these researchers have contributed to the understanding of a broad variety of phenomena including phylogenetics and genomics, and the formation and role of fossils.
The word "theory" is sometimes used to refer to a speculation or guess however it actually refers to a scientific idea that has been thoroughly developed and tested over time. Scientists test their theories by repeating the experiment or observations that resulted in them. Therefore, the theory of evolution has been repeatedly proven out as have the corresponding theories of Copernican, atomic and germ theory.
What is the Process of Evolution?
The process of evolution is the gradual shift over time in the ratio of genetically distinct individuals within a particular species. This change is a result of natural selection of those who are more well-adapted to their environment. The more adapted individuals have higher chances of reproduction and survival. As more of these people survive and reproduce their genes are more prevalent in the population. This is sometimes referred to as "survival for the fittest."
According to the theory of evolution the mutations that result in genomic variation are the primary basis for evolutionary change. These mutations may occur at random or under the influence of the environment. When mutations are random the frequency of the resultant alleles could differ from generation to generation. If a mutation is beneficial it will increase the frequency of alleles, causing the allele to be spread across the population.
Over time, these shifts in allele frequencies could result in the creation of new species. The new species will then grow and evolve into new forms. This process is called macroevolution. The formation of new species is typically a result of changes in the environment which makes certain resources available or creates new environmental issues. For instance, the rise of finches in the Galapagos Islands is a result of the abundance of food sources and the need defend themselves from predators.
In a wider context, evolution is defined as any change that takes place in the traits of organisms over time. The change could be minor or even the creation of a new coloration, or massive, for instance, the development of a brand new organ.
Scientists who believe in evolution theory generally agree that genetic change is essential in creating evolution. They also believe that evolution is a process that occurs in time, typically over a period of millions of years. However, they differ over the importance of different factors that speed up or slow down the process, including the role of environmental pressures, sexual selection, and mutation bias. Despite these differences most scientists believe that evolution is real and that the evidence in support of this is overwhelming.
What 에볼루션 블랙잭 do we have to support evolution?
Since Darwin's time, scientists have gathered evidence to support his theory of evolution. This evidence comes from fossils which show the evolution of organisms over time. Similarities between living and non-living organisms as well as embryology, biogeography, and genetics are also evidence.
The primary evidence of evolution can be found in the evolutionary tree, which shows how species are related. Another evidence source is homologous structures, which have similar structures in different species but serve different purposes like the wings of birds and bats. The fact that different species develop and adapt to the same environment is another sign of evolution. For example, arctic foxes and ptarmigans have seasonal white pelts to blend into snow and ice. This is a kind of convergent evolutionary process which suggests that the species share ancestors.
Another source of evidence is vestigial structures, which are unutilized organs which could serve a purpose in a distant ancestor. The human appendix for instance is an odour from an organ that was once used to digest food. Natural selection causes these structures to shrink as they are no longer used.
Scientists have also gathered evidence for evolution through observation and experimenting. The evidence for evolution can be grouped into six categories: directly observed small-scale changes, biogeographic patterns, comparative anatomy, the fossil record, genetics, and classification. Each of these provides convincing evidence that evolution of life has occurred.
Many people have misconceptions regarding the theory of evolution. However, it is a fact. It is not just a theory; it is a potent collection of years of observations and data that has been tested and proven. Scientists continue to gather and analyze new data to better understand the arc of the Earth's life, 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 make the most of our planet's resources. It will also allow us to better meet the needs of the people on this planet.