Editing Paleontology (section)

===Paleophysiology===
{{main|Paleophysiology}}
Paleophysiology is the study of how ancient life coped with its chemical and physical surroundings. Much is known about [[physiological]] changes on a short time scale, but less so about long-term responses including genetic modification. Paleophysiological analysis can investigate how species evolved or went extinct from gradual or rapid environmental change and apply that to modern scenarios to predict responses in the future. Past geological records can be found that resemble those predicted for the future. Extinctions of ancient organisms tend to be selective to certain traits like [[metabolic rate]], temperature tolerance, [[photosynthesis]] and [[homeostasis]], but much is not yet understood about the physiology of ancient organisms. The most useful tool for assessing paleophysiology is through the studies of "[[living fossils]]" that has presumably changed very little physiologically over long periods of time and therefor can be used to indicate paleophysiological conditions. It remains largely unknown how calcifying organisms built robust skeletons at times when atmospheric carbon dioxide levels were high, but the understanding of this process can be applicable to current rising carbon dioxide levels. Similar work may explain how photosynthetic corals and reefs can exist in times of higher acidity and temperatures as in the past. Plants respond to changes in temperature, [[precipitation]], soil quality, and atmospheric gas composition, which can be seen in their fossils. Fossils offer a large array of phenotypes and physiologies that are rare or absent in modern biotas making it possible to assess adaptations that are not found in living species.<ref name="vermeij2015"/>