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Extinction coefficient refers to several different measures of the absorption of light in a medium: Attenuation coefficient , sometimes called "extinction coefficient" in meteorology or climatology Mass extinction coefficient , how strongly a substance absorbs light at a given wavelength, per mass density
An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth.Such an event is identified by a sharp fall in the diversity and abundance of multicellular organisms.
Ceballos pointed to the extinction of the passenger pigeon, which was the only species in its genus, as an example of how losing a genus can have a cascading effect on a wider ecosystem.
Changes in sea level and chemistry? [39] Mulde event: 424 Ma: Global drop in sea level? [40] Ireviken event: 428 Ma: Deep-ocean anoxia; [41] Milankovitch cycles? [42] Ordovician: Late Ordovician mass extinction: 445-444 Ma Global cooling and sea level drop, and/or global warming related to volcanism and anoxia [43] Cambrian: Cambrian ...
The conservation of mass was obscure for millennia because of the buoyancy effect of the Earth's atmosphere on the weight of gases. For example, a piece of wood weighs less after burning; [17] this seemed to suggest that some of its mass disappears, or is transformed or lost. Careful experiments were performed in which chemical reactions such ...
There is evidence of a mass extinction of bony fishes at a fossil site immediately above the K–Pg boundary layer on Seymour Island near Antarctica, apparently precipitated by the K–Pg extinction event; [90] [91] the marine and freshwater environments of fishes mitigated the environmental effects of the extinction event. [92]
Because the modern rate of carbon release exceeds the PETM's, it is speculated the a PETM-like scenario is the best-case consequence of anthropogenic global warming, with a mass extinction of a magnitude similar to the Cretaceous-Palaeogene extinction event being a worst-case scenario. [222]
The Signor–Lipps effect is a paleontological principle proposed in 1982 by Philip W. Signor and Jere H. Lipps which states that, since the fossil record of organisms is never complete, neither the first nor the last organism in a given taxon will be recorded as a fossil. [1]