Fern spike

From Wikipedia, the free encyclopedia

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.

[edit] 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