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The end all *clickey*
Evidence
For those of you who dont want to read that, Ill summerize some bits of it; (its a bit long, read it or dont, but dont whine about how long it is)
Quote: Description
Evolution is the process by which populations of organisms acquire and pass on novel traits from generation to generation. Its action over large stretches of time explains the origin of new species and ultimately the vast diversity of the biological world.
The understanding of evolution is based on the theory of natural selection, natural selection is the idea that individual organisms which possess variations giving them advantageous heritable traits are more likely to survive and reproduce and, in doing so, increase the frequency of such traits in subsequent generations.
Quote: Evidence of Evolution
The process of evolution has left behind numerous records which reveal the history of different species. While the best-known of these are the fossils, fossils are only a small part of the overall physical record of evolution. Fossils, taken together with the comparative anatomy of present-day plants and animals, constitute the morphological record. By comparing the anatomies of both modern and extinct species, biologists can reconstruct the lineages of those species with some accuracy. Using fossil evidence, for instance, the connection between dinosaurs and birds has been established by way of so-called "transitional" species such as Archaeopteryx.
Although we cannot obtain the DNA sequences of most extinct species, the degree of similarity and difference among modern species allows geneticists to reconstruct lineages with greater accuracy. It is from genetic comparisons that claims such as the 95% similarity between humans and chimpanzees come from, for instance.
Other evidence used to demonstrate evolutionary lineages includes the geographical distribution of species. For instance, monotremes and most marsupials are found only in Australia, showing that their common ancestor with placental mammals lived before the submerging of the ancient land bridge between Australia and Asia.
Scientists correlate all of the above evidence – drawn from paleontology, anatomy, genetics, and geography – with other information about the history of the earth. For instance, paleoclimatology attests to periodic ice ages during which the climate was much cooler; and these are found to match up with the spread of species such as the woolly mammoth which are better-equipped to deal with cold.
Quote: The Beginning
The chemical evolution from self-catalytic chemicals to life is not a part of biological evolution.
Not much is known about the earliest developments in life. However, all existing organisms share certain traits, including cellular structure, and genetic code. Most scientists interpret this to mean all existing organisms share a common ancestor, which had already developed the most fundamental cellular processes, but there is no scientific consensus on the relationship of the three domains of life (Archaea, Bacteria, Eukaryota) or the origin of life. Attempts to shed light on the earliest history of life generally focus on the behavior of macromolecules, particularly RNA, and the behavior of complex systems.
The emergence of oxygenic photosynthesis (around 3 billion years ago) and the subsequent emergence of an oxygen-rich, non-reducing atmosphere can be traced through the formation of banded iron deposits, and later red beds of iron oxides. This was a necessary prerequisite for the development of aerobic cellular respiration, believed to have emerged around 2 billion years ago.
In the last billion years, simple multicellular plants and animals began to appear in the oceans. Soon after the emergence of the first animals, the Cambrian explosion (a period of unrivaled and remarkable, but brief, organismal diversity documented in the fossils found at the Burgess Shale) saw the creation of all the major body plans, or phyla, of modern animals. This event is now believed to have been triggered by the development of the Hox genes. About 500 million years ago, plants and fungi colonized the land, and were soon followed by arthropods and other animals, leading to the development of land ecosystems with which we are familiar.
Quote: Misconceptions about modern evolutionary biology
Many critics of evolution claim that the theory robs life and the universe of any transcendental meaning. Indeed, one of the great strengths of evolution by natural selection is that it has no need for a supernatural intelligence or any intelligent design. As Louis Menand has pointed out, what was radical about Darwin's theory of speciation through natural selection was not the notion of evolution — a concept people espoused before Darwin, and a word that does not appear in The Origin of Species — but his materialism: "Darwin wanted to establish ... that the species — including human beings — were created by, and evolve according to, processes that are entirely natural, chance-generated, and blind" (Menand 2001: 121).
Nevertheless, many critiques of the modern evolutionary thought involve misunderstandings of the theory itself, or of science in general.
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