Question
Mention three important features of fossils which help in the study of evolution.
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Answer
Fossils are remains or impressions of past organisms that are found in the rocks. Fossils of lower strata belong to early periods while those of upper strata are of later periods. Arranging the fossils stratumwise will indicate the occurrence of different forms of life at different times. It is found that the early fossils generally belong to simple organisms. Complexity and elaboration increased gradually with evolution. Evolution has never been linear or straight. A number of variants or branches appeared, some of which were more complex while others were less complex. Fossils indicate the path of evolution of different groups.They can indicate the phylogeny of some organisms, e.g, Horse, Elephant.
Some fossils have characteristics intermediate between two groups, e.g., toothed bird Archaeopteryx. They indicate how one group has evolved from another.
Some fossils have characteristics intermediate between two groups, e.g., toothed bird Archaeopteryx. They indicate how one group has evolved from another.
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