A1: descent with modification
Q2: what are the two different ways of evolution?
A2: the pattern of evolutionary change is revealed by data from a range of scientific disciplines.
the process of evolution consists mechanisms that produce the observed pattern of change.
Q3: what are the three key obervations about life?
A3: the stricking ways in which organisms are suited for life in their environment; the many shared characteristics of life; and the rich diversity of life.
Five Facts:
1. the Darwinian revolution challanged traditional view of a young Earth inhabited by unchanging species
2. descent with modification by ntural selection explains the adaptations of organisms and the unity and diversity of life.
3. Evolution is supported by an overwhelming amount of scientific evidence
4. individuals that are well suited to their enironment tend to leave more offspring than other individuals.
5. favorable traits accumulate in the population
Figure:
Summary:Aristotle viewed species as fixed, scala naturae. Carolus Linnaeus adopted classification system. Fossils are the remains or traces of organisms from the past. New layers of sediment cover older ones and compress them into superimposed layers of rock called strata. Palenotolgy is the study of fossils developed by Georges Cuvier. Catastrophism is the principle that events in the past occurred suddenly and were caused by mechanisms different from those operating in the present. Charles Lyell 's uniformitarianism stated that mechnisms of change are constent over time.Lamarck hypothesized that species evolve, but the mechanisms he proposed are not supported by evidence.
Darwin's voyage gave him lots of experience and evidences. Adaptations are characteristics of organism that enhance their survival and reproduction in specific environment. In his book The Origin of Species: that descent with modification explains life's unity and diversity and that natural selection brings about the match between organisms and their environment. Artifical selection is the process that humans have modified other species over many generations by selecting and breeding individuals that possed desired traits. Individuals do not evolve; traits are passed from organismms to their offspring; environmental factors vary form place to place and over time.
Predators are a potent force in shaping the adaptations of their food source. HIV is an example of drug-resistant pathogens. Natural selection is a process of editign rather than a creative mechanism. Natural selection depends on time and place. Similarity resulting from common ancestry is known as homology. Homologous structures that represent variations on a structureal theme that was present in their common ancestor. Vestigial structures are remmnants of features that served important functions in the organims's ancestors. Evolutionary tree is a diagram that reflects evolutionary relationship among groups of organims. Convergent evolution is the independent evolution of similar features in different lineages. Analogous is species share features because of convergent evoluion. Biogeography is the geographic distribution of species, including continetal drift. The origial single large contnent is Pangaea.
Video:evolution
http://www.youtube.com/watch?v=19PfUIovUaU&feature=related
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