Totally off topic here, Sarda, but could I beg for some commentary, in your far more educated opinion, about "Romer's Gap"?doubleplusuberthanx.PS I missed the meme infection because I took my family down to the .
Hey Will, hope this helps, Let me know if you have more questions. SardaRomer’s Bottleneck, coined by Coates and Clack (1995) is a gap in the fossil record of tetrapods between the Late Devonian tetrapods and the Visean. Horton Bluff, Nova Scotia is the best known Tournaisian fauna to date but consists of disarticulated elements (Carroll and Heatwole 2000). The gap was originally about 20-30 Myr of time but has been defined more narrowly, as having occurred 360-345 Ma, a period of time roughly equivalent to the Tournaisian (Ward et al. 2006). The nature of the gap has been debated. Some palaeontologists believe it is a deficiency of the fossil record caused by low preservational potential (Carroll 2001), but others think it was a true diversity loss in the fossil record. Notably, Jenny Clack believes it was actually a time of great gains in diversity, hence the gap is an artifact of the fossil record. However, Ward, Labandeira et al. (2006) examined the diversity of insects and tetrapods from 450 Myr to 290 Myr, they found a correlation between a diversity hiatus in insects, a drop in tetrapod diversity and decreased oxygen levels. Carroll, R. L. 2001. The origin and early radiation of terrestrial vertebrates. Journal of Paleontology 75:1202-1213.Carroll, R. L., and H. Heatwole. 2000. Amphibian biology: palaeontology. Surrey Beatty & Sons, Chipping Norton.Coates, M. I., and J. A. Clack. 1995. Romer's Gap - tetrapod origins and terrestriality. Pp. 373-388 in M. Arsenault, H. Lelièvre, and J. P., eds. Miguasha: Studies on Early Vertebrates. Muséum National de’l Histoire Naturelle, Paris.Ward, P., C. Labandeira, M. Laurin, and R. A. Berner. 2006. Confirmation of Romer's Gap as a low oxygen interval constraining the timing of initial arthropod and vertebrate terrestrialization. Proceedings of the National Academy of Sciences 103:16818-16822.
ees a swimming whale!!!! yay!!!!
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