In paleontology, a fern spike is the occurrence of abundant fern spores in the fossil record, usually immediately (in a geological sense) after an extinction event. The spikes are believed to represent a large, temporary increase in the number of ferns relative to other terrestrial plants, probably because of the extinction or thinning of the latter. Fern spikes are most associated with the Cretaceous-Tertiary extinction event^[1][2], although they have been found at other events such as at the Triassic-Jurassic boundary^[3][4]. Away from the fossil record, fern spikes have also been observed to occur in response to local extinction events, for instance the 1980 Mount St. Helens eruption. Paleontology or palaeontology (see Spelling differences) is the study of the history and development of life on Earth, including that of ancient plants and animals, based on the fossil record (evidence of their prehistoric existence as typically preserved in sedimentary rocks). ... Classes Psilotopsida Equisetopsida Marattiopsida Polypodiopsida A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta. ... This article is about a biological reproductive structure; for the video game, see Spore (video game). ... It has been suggested that this article or section be merged into Fossil. ... An extinction event (also known as: mass extinction; extinction-level event, ELE) occurs when there is a sharp decrease in the number of species in a relatively short period of time. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) †Rhyniophyta - rhyniophytes †Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses †Trimerophytophyta - trimerophytes Pteridophyta - ferns and horsetails Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... The Dodo, shown here in illustration, is an often-cited[1] example of extinction. ... Thinning is in forestry a type of selective cutting primarily undertaken to make the forest more profitable in an upcoming final felling. ... Badlands near Drumheller, Alberta where erosion has exposed the KT boundary. ... The Triassic is a geologic period that extends from about 251 to 200 Ma (million years ago). ... // The image above is believed to be a replaceable fair use image. ... (Redirected from 1980 Mount St. ...

References

1. ^ Schultz, P.H. and D'Hondt, S. (1996) Cretaceous-Tertiary (Chicxulub) impact angle and its consequences. Geology 24, 963-967
2. ^ Vajda, V., Raine, J.I. and Hollis, C.J. (2001) Indication of global deforestation at the Creataceous-Tertiary boundary by New Zealand fern spike. Science 294, 1700-1702
3. ^ Fowell, S.J. and Olsen, P.E. (1993) Time calibration of Triassic-Jurassic microfloral turnover, eastern North-America. Tectonophysics 222, 361-369
4. ^ Olsen, P. E., Kent, D.V., Sues, H.D., Koeberl, C., Huber, H., Montanari, A., Rainforth, E.C., Fowell, S.J., Szajna, M.J. and Hartline, B.W. (2002) Ascent of dinosaurs linked to an iridium anomaly at the Triassic-Jurassic boundary. Science 296, 1305-1307