Evolution can be defined as the process through which the characteristics of a species undergo changes over a number of generations through the process of natural selection. There are different mechanisms that try to explain the evolution process and these are mutation, migration, genetic drift and natural selection. However for natural selection and genetic drift to take place there must exist a certain type of genetic variation. To begin with natural selection can be defined as the process through which organisms that are better adapted to a certain environment survive and produce fertile off springs. Organisms that do not seem to adapt in that particular environment are left out.
He paid more attention to the varieties of individuals during his work on barnacles, domestic plants and animals. The variability is an important part of natural selection and the most important aspect of evolution. The article “Brief Essay on the Darwin’s Theory of Natural Selection” written on PreserveArticles.com indicates, “The differences of offsprings from their same species are called variations. […] Such variations were of two kinds, some were inheritable while others were not inheritable” (Vijaykant, par. 12).
An Introduction to Evolution What is Evolution? Evolution is the process by which all living things have developed from primitive organisms through changes occurring over billions of years, a process that includes all animals and plants. Exactly how evolution occurs is still a matter of debate, but there are many different theories and that it occurs is a scientific fact. Biologists agree that all living things come through a long history of changes shaped by physical and chemical processes that are still taking place. It is possible that all organisms can be traced back to the origin of Life from one celled organims.
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.
Evolutionary ecologists are aware that not only intrinsic factors constrain how organisms use their habitat, but the environment itself have implications for a species ability to colonise new areas (Holt 2003). Predicting how species will respond to environmental change such as their ability to track optimal habitats and adapt to changing conditions, depends on understanding these mechanisms will be important. The distance that an organism travels can tell us something about their preferred habitat, how they reproduce as well as being a primary determinant of their likelihood to survive. Dispersal between populations influences the likelihood of colonisation and extinction. If extinction occurs in one habitat patch populations may be rescued by individuals from a nearby population.
Essay on Evolution There are many mechanisms that lead to evolutionary change. One of the most important mechanism in evolution is natural selection which is the differential success in the reproduction of different phenotypes resulting from the interaction of organisms with their environment. Natural selection occurs when a environment makes a individual adapt to that certain environment by variations that arise by mutation and genetic recombination. Also it favors certain traits in a individual than other traits so that these favored traits will be presented in the next generation. Another mechanism of evolution is genetic drift.
There have been many ideas on the theory of evolution. Some simply take our existence for granted, others prefer to explain all evolution in terms of the bible and the presence of a God. However, there are those who have researched the topic of evolution and have offered an explanation as to where a species comes from and how they evolved in the manner that they did. This type of science has been studied for a very long time, and one of the most famous minds in the field of evolution was a man named Charles Darwin. Darwin was not the first one to offer theories on evolution.
Overall, Charles Darwin had a theory and proved that animals and plants have evolved in an orderly manner and evolving. He lived an extraordinary life traveling, studying and discovering on the HMS Beagle and the Galapagos Islands. Darwin believed that evolution occurred because of natural selection, or known as the survival of the fittest. Many people did not agree with his theory of evolution because it went against all religious thoughts of creation. However, the scientist believed that this was the start of biology.
It led biologists to concentrate on the diversity of organisms, their origins and their relation, their similarities and their differences, their geographical distribution and their adaptation to various environments. Darwin (1859) arrived at two main conclusions. • All species on earth descend from ancestral species and he presents a mechanism explaining evolution called natural selection. • Natural selection results in adaptive evolution (prevalence of hereditary characteristics favouring the survival and the reproduction of organisms in different environments). Evolution: Historical Controversy In order to fully understand Darwin’s vision, it is important to understand the historical context and compare it to the previous ideas on Earth and life on Earth.
On the other hand, through studies of comparative embryology, the fossil record, and comparative anatomy, evolutionists have found evidence that both directly and indirectly support the theory of evolution. A biological textbook states that evolution is "the origin of organisms by descent and modification from previously existing forms of life" (Arms and Camp 325). Therefore, evolution is the process that forms all life on Earth. Each species found on Earth today is a modified descendent of a previous species of organisms. Evolution's most significant mechanism is natural selection.