As populations of species moved into new habitats and new parts of the world, they faced different environmental conditions. Over time, these populations accumulated modifications, or adaptations, that allowed them and their offspring to survive better in their new environments. These modifications were the key to the evolution of new species, and Darwin proposed natural selection or "survival of the fittest" as the vehicle by which that change occurs. Under Natural Selection, some individuals in a population have adaptations that allow them to survive and reproduce more than other individuals. These adaptations become more common in the population because of this higher reproductive success.
(C.Darwin, 1859) Two notable scientists associated with the theory of evolution include Charles Darwin and Jean-Baptiste Lamarck. Charles Darwin contributed majorly to the evolutionary theory and was the first to consider the concept of natural selection. The evolutionary theory states that evolutionary change comes through the production of genetic variation in each generation and survival of individuals with different combinations of these characters. Individuals with characteristics which increase their probability of survival will have more opportunities to reproduce and their offspring will also benefit from the heritable, advantageous characteristic. So over time these variants will spread through the population.
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.
DNA fingerprinting and modern genetics can be utilised to document the history evolution. By studying variation among species, scientists are able to learn more about the changes that occurred in species over time. Scientists can compare DNA sequences of similar species and can discover information about their behaviour, relationships and appearances. Discoveries in modern genetics have also provided substantial evidence that species evolved from a common ancestor. There are still many gaps in the understanding the evolutionary process, but modern genetics has successfully proven that living species share a common hereditary system.
The first person who proposed natural selection in 1858 was the English scientist Charles Darwin. According to Darwin’s theory, mutated genetic traits, which allow an individual to survive environmental changes, prevail and are passed on to the offspring. The offspring, having inherited the mutated traits, reproduces again and expands the population with the new traits. This new offspring and population have passed through the process of Natural Selection and survived. In comparison, individuals without the mutated genes or with less desirable traits may have a harder time surviving natural obstacles.
Within these organisms there are different variations. Those variations are then inherited from parent to offspring; generation after generation. The organism with inherited characteristic that help with survival and reproduction are selected amongst the different variations of that organism. They are then able to reproduce more than others and therefore they are able to pass down their traits to one generation on to the next. Darwin’s theory of natural selection explained adaptations that helped a species to survive.
I became interested in this topic because it hard for me to think at one time humans had tails, or that some species of ape’s DNA is very similar to ours. Darwin 's theory of evolution states that all life is related in one way or another. He explains this by saying that due to random gene mutations form more advanced organisms from their simplistic counterpart. This feeds into the second half of his theory. This part of the theory is natural selection, or survival of the fittest.
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).
So somehow all species are somewhat connected. The basis of what Darwin was proving was that life on Earth is simply the result of billions of years of adaptation to the changing environments. That is why certain species can only live in certain climates. This can be explained with the color of your skin, or the growing of plants. The color of your skin used to depend on where you live.
Genetic diversity is crucial for adapting to new environments, as more variation in genes leads to more individuals of a population having favorable traits to withstand harsh or changing conditions of their environment. This genetic diversity is what allows for evolution to occur through “survival of the fittest”. Organisms with genes and characteristics more suited for their environment have a better chance at survival. Low genetic diversity can be very problematic in changing environments, as all individuals will react similarly. This similar reaction is caused by their similar genetic makeup.