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Period: to
time line of evalution
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Buffon
in 1700's two church doctines provided sweeping ecplanations for biological diversity. Separate creation, examlpe, all creatures were created independently of one another by God. Life forms were organized into a herachy ("chain of being") with Man occupying the most elevated rank beneath God. In the 1700's in was generally accepted that the age of the earth was 6000 years old. He was one of the first of many scientists to challenge publicly the idea that life forms are uncghanged. -
Lamark
Compared current species with fossil forms. He observed what he called a "line of descat" or progression. This progression led to a modern specices. He belived that species increased there complexity over time until they have acheived perfection. this theory also thought aquired characteristics could be inherited by the offspring. this was called "Zhenitare of aqired characteristics" so Lamark belived adaptations to the enviroment could be passed on to the next generation. -
Cuvier
largely created with developing the science of palentology. noticed that each strata of rock is characteristics by unique fossil types. The deeper the stratum the more disimillar from the modern the species became. This evedince showed the speices could become extinct. -
Lyell
Recected Coviers idea om many catastrophic events. suggested that geological process operated at the same rates in the past as they do today. if changes are slow and continous rather than catastophic the earth must be older that 6000 years. forces that built and erode mountains happen no differently today than in the past. floor in the past had no greater power than floods that occur today, Example, no global flood. if earth is slowly changing,could slow and suddle changes also occur population -
Darwin
Natural selection is the gradual,nonrandom process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers.It is a key mechanism of evolution.Variation exists within all populations of organisms.This occurs partly because random mutations cause changes in the genome of an individual organism, and these mutations can be passed to offspring.Throughout the individuals lives, their genomes interact with their enviroment -
Wallace
When Darwin and Wallace read Malthus, it occurred to both of them that animals and plants should also be experiencing the same population pressure. It should take very little time for the world to be knee-deep in beetles or earthworms. But the world is not overrun with them, or any other species, because they cannot reproduce to their full potential. Many die before they become adults. They are vulnerable to droughts and cold winters and other environmental assaults.
