Paleoenviroment

Paleoecology (also spelled palaeoecology) is the study of interactions between organisms and/or interactions between organisms and their environments across geologic timescales. As a discipline, paleoecology interacts with, depends on and informs a variety of fields including paleontology, ecology, climatology and biology.

Paleoecology emerged out of the field of paleontology in the 1950’s, though paleontologists have conducted paleoecological studies since the creation of paleontology in the 1700s and 1800s. Combining the investigative approach of searching for fossils with the theoretical approach of Charles Darwin and Alexander von Humboldt, paleoecology began as paleontologists began examining both the ancient organisms they discovered and their environments. Visual depictions of past marine and terrestrial communities has been considered an early form of paleoecology.

Assumptions - While the functions and relationships of fossil organisms may not be observed directly (as in ecology), scientists can describe and analyze both individuals and communities over time. To do so, paleoecologists make the following assumptions:

The aim of paleoecology is therefore to build the most detailed model possible of the life environment of previously living organisms found today as fossils. Such reconstruction takes into consideration complex interactions among environmental factors such as temperatures, food supplies, and degree of solar illumination. Often much of this information is lost or distorted by the fossilization process or diagenesis of the enclosing sediments, making interpretation difficult.

The environmental complexity factor is normally tackled through statistical analysis of the available numerical data (quantitative paleontology or paleostatistics), while the study of post-mortem processes is known as the field of taphonomy.

Much of the original paleoecological research has focused on the last two million years (the Quaternary period), because older environments are less well represented in the fossil timeline of evolution. Indeed, many studies concentrate on the Holocene epoch (the last 11,500 years), or the last glacial stage of the epoch (the Wisconsin/Weichsel/Devensian/Würm glaciation of the ice age, from 50,000 to 11,500 years ago). Such studies are useful for understanding the dynamics of ecosystem change and for reconstructing pre-industrialization ecosystems.

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