paleantology
One of the principal objectives of geologists studying sedimentary rocks is the reconstruction of the environment in which the rocks were deposited. Correct reconstruction may result in the discovery of oilfields, deposits of salts, or base metals, and provide insight to our earth's past. As evidence to ancient environments the geologist has the structures, textures, and composition of the grains that make up the sediments, and the fossils preserved in them. Organisms are far more sensitive to, and therefore diagnostic of, the environment in whixh they live than are the grains of sediment to the environment in which they were deposited. A study of the way of life and environmental requirements of organisms that become fossils therefore yields the most accurate information about the environment in which sediments were formed.Ecology is the study of the relations between modern organisms and the environments in which they live; paleoecology is the study of these relations between species represented in the fossil record and the environments they inhabited. Unlike ecologists, the paleoecolgist has to work with organisms that are no longer alive and are very often misrepresented in the fossil record. Despite the limitations o
The fossils of living species whose temperature tolerance is known are obviously of value for determining temperatures of ancient seas. However, most fossil species are extinct, and their tolerances are not directly known. Comparing the morphology of the fossils to those of modern organisms can often lead to conclusions concerning their adaptation to a specific climate. For example, the plants of tropical rainforests have large leaves with tips shaped for dripping moisture, and large breathing pores; these features in extinct fossil plants, such as those of the coal forests, are interpreted as indicative of warm, moist climates. Most of paleoecological reconstruction is based on inference from modern organisms and their function in their ecosystem. Although it is not easy to specify the detailed behaviour of an extinct organism, there are certain constraints in the environment that almost certainly applied to the past as they do to the present, since they are largely based on invariant laws of chemistry and physics. In many cases a uniformitarian approach to paleoecology is justified, and we can clearly which conditions an ancient condition must have tolerated and which ones they could not. Important physical parameters of the environment such as temperature, light, salinity, nature of the soil or bottom sediment, and rainfall must have had the same effect on living oraginisms in ancient ecosystems as they do today. Other direct peleoecological evidence is more scientific in nature, often called paleobiogeochemistry. This study is based on the chemistry of the shell or the bone of the fossil, and often tells a lot more than the fossil
Some common words found in the essay are:
Behaviou Coevolution, , Fossils Life, modern organisms, preserved organisms, paleoecological evidence, oxygen isotopes, direct evidence, paleoecological reconstruction, ancient environments, modern communities, ancient ecosystems, isotope levels,
Approximate Word count = 1116
Approximate Pages = 4 (250 words per page double spaced)
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