Evolution Of A Evolutionary Theory

1500 WordsFeb 20, 20166 Pages
Evolution is descent with modification, a phrase Darwin used in proposing the at Earth’s many species are descendants of ancestral species that were different The power of evolution as a unifying theory is its ability to explain and connect a vast array of observations about the living world. Aristotle believed that life forms could be arranged on a scale of increasing complexity. Each form of life, perfect and permanent, had its allotted space. Darwin argued that classification should be based on evolutionary relationships Darwin used fossils, the remains or traces of organisms from the past, to study and observe change over time. Paleontology is the study of these fossils Darwin said that if geologic change results from slow, continuous actions rather than from sudden events, then the Earth must be much older than what was previously thought. Lamarck used two main principles already accepted to prove his evolutionary theory. The first was use and disuse, the idea that parts of the body that are used extensively become larger and stronger. The other was inheritance of acquired characteristics, which stated that an organism could pass these modifications to its offspring. Lamarck’s idea that organisms have an innate drive to become more complex was rejected by Darwin. Darwin reasoned that over a long time, descent with modification eventually led to the rich diversity we see today. Closely related species that are very similar due to their common ancestor, until they
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