Later he took a five year excursion on the HMS Beagle. While on the Galapagos Islands he noticed that the finches on the each island were closely related but different in big ways. When he returned, he theorized evolution based on natural selection. Twenty years later he and Alfred Russell Wallace discussed evolution openly. In he published his extremely controversial ideas. Darwin was attacked for his theory, particularly by the Church. But his ideas became widely accepted.
Erasmus did not come up with natural selection, but he did believe in competition and sexual selection. He believed that the strongest males reserved the right to mate, therefore passing on satisfactory traits. He used an integrative method of research, bringing together multiple branches of science to come to his conclusion.
Some of his ideas were alike to those of Jean Baptiste Lamarck. Lamarck is an obscure character in evolutionary history as he was ostracized and his theories were not recognized by his colleagues. He was in the army, then worked as a botanist in the royal gardens. In , Lamarck was appointed professor of invertebrates. At the time there was little research on insects.
He wrote a series of books about invertebrate zoology and paleontology. Although other scientists in his day hinted at the possibility of evolution, Lamarck declared it forthright. He was discredited by his peers and died a poor man. However, Charles Darwin and others respected his as a great zoologist and the forerunner of evolutionary theory. Cuvier had studied mummies of cats and ibises brought back from Egypt by Napoleon. Finding no difference from current day animals, he had decided evolution was false.
He later studied elephants and mammoth fossils, determining that mammoths were different from living elephants in their day. This led to the important idea of extinction.
Macroevolution is evolution on a grand scale. Instead of focusing on a single branch, macroevolution focuses on that chunk of the tree. It identifies patterns and transformations, then figures out how and why it happened. Mutation, migration, genetic drift, and natural selection are basic mechanisms that apply to both micro- and macroevolution to determine these patterns.
Changes and extinctions that have happened over the years are all part of macroevolution. Some changes take place slowly, this is called stasis. Extinction is an important part of evolution. Every species has a chance that it will become extinct.
Microevolution is an even more important part of the evolutionary theory. As previously discussed, it is evolution on a small scale. It is the changes in animals to adapt to their habitats and the changing environment.
Microevolutionairy changes can be seen by changes in gene frequency. A few of the mechanisms that affect these changes are mutation, migration, genetic drift, and natural selection. The genes in the yellow bird would have been mutated to produce purple chicks.
The typical view of the nature of species at the beginning of the nineteenth century is often described as the Doctrine of Fixed Species. This concept had its primary roots in Greek philosophy: During the eighteenth century, Carolus Linnaeus developed the basis for our nested, hierarchical classification system, or Taxonomy.
The geologic discipline of stratigraphy was developed during the late eighteenth and early nineteenth centuries.
Though this accomplishment was shared by many geologists throughout Europe, the name most commonly associated with developing the concept of stratigraphy is William Smith , who was an engineer engaged in building canals all over England. George Cuvier eventually Baron George Cuvier was a scientist of the late 18th and early 19th centuries.
His specialty was vertebrate anatomy. Because of his expertise in anatomy, Cuvier was the obvious person to ask to examine strange remains found during reconstruction after a major Paris fire. These remains turned out to belong to extinct organisms, and led to the development of the field of study we call Paleontology. Cuvier was the first to reconstruct dinosaurs.
Cuvier is also remembered for coming up with the concept of Catastrophism, as an attempt to reconcile his religious beliefs with the evidence he discovered as a scientist.
Charles Lyell , a British geologist, developed the concept of Uniformitarianism. In other words, the forces acting upon and shaping the Earth today are the same as the forces that acted upon and shaped the Earth in the past. Uniformitarianism is a central tenet of modern geology. Darwin was born in the first century of the nineteenth century to a wealthy family.
His hobby was natural history. He collected beetles, went on geological field trips and became very friendly with the natural history faculty at his universities. During the five-year trip, he collected tons literally of specimens of animals, plants and fossils, which he shipped back to England for later analysis.
Upon returning to England, he officially became a naturalist. Almost all of his specimens were sent to experts for analysis. He kept the barnacles for himself, setting out to become an expert in barnacles. It was the analyses that were returned to him from his experts that started him thinking along revolutionary pathways.
Thus, in order for humans to continue to survive, some have to die. One reason he finally published in and then published Origin of Species in was that he discovered that another man, Alfred Russell Wallace , had independently discovered and was about to publish exactly the same theory Darwin had been working on for 20 years. Darwin saw a clear pattern of common descent among the species of life. Examining the expert analyses of all of the specimens from the Beagle expedition, it was clear to Darwin that the various forms of life were all descended from one, or many from a very few, common ancestral species.
The mechanism Darwin figured out by which species could change from one thing into something different was natural selection.
He saw environmental competition as providing the selective pressure in nature. All living things tend to over-reproduce. There will be competition over resources, and not all members of any generation can survive. Many aspects of variation are heritable, meaning that they are passed from parents to offspring.
Each new generation will tend to be more like the successful parents and less like the unsuccessful parents. Given enough time meaning enough generations , these changes can produce brand new species, especially if the environmental pressure is strong. What is the evidence in support of the theory of evolution?
This question could take weeks to answer. Observations of a wide variety of phenomena demonstrate evolutionary action and consequences. Here are some examples:. Adaptive radiation, which Darwin saw abundantly demonstrated among the species he observed and collected while on the Beagle. Adaptive radiation is the phenomenon in which a single species splinters into many daughter species.
This phenomenon is very commonly observed among species living on off-shore islands like the Galapagos Islands to the west of South America. The fossil record abundantly demonstrates evolutionary change. Transitional sequences show, for instance, the emergence of mammals from reptiles in the Permian Period, and the emergence of Cetaceans from terrestrial mammals in the early Cenozoic Era.
Biogeography the distribution of species geographically abundantly supports evolution, specifically island biogeography, which shows us that the resident species of islands are always derived from the species on the adjacent mainland. Signatures of History are abundant in virtually all species.
These are physical or behavioral features which clearly show that the modern species is descended from a species that lived a different kind of life cycle. Molecular sequencing is an area of evidence that Darwin could never have predicted. Our modern biotechnology allows us to compare DNA and protein sequences among living organisms. Molecular sequencing has provided a superb method of directly testing the predictions of evolutionary theory.
Research Papers words | ( pages) | Preview Darwin's Theory of Evolution - "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life," usually shortened to "the Origin of Species," is the full title of Charles Darwin's book, first published in , in which Darwin formalized.
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.
May 16, · Evolution Essay Evolution is the theory that all living forms came from ancient ancestors. Through a series of mutations, genetic drift, migration, and natural selection today’s descendants show an amazing amount of similarities and diversity. Essays in Natural History and Evolution THE ESSAY in science is an art form as well as a means of communicating ideas. All scientists publish their findings somewhere, but .
Help and advice with writing an essay on evolution. How to outline and write your assignment on evolution.5/5. Free Essay: Evolution Evolution is a complex process by which the characteristics of living organisms change over many generations as traits are passed from.