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Re: Tinirau, new Devonian marine stem-tetrapod



The paragraph that will be of the widest interest:

"However, the phylogenetic distribution of potential sarcopterygian trackmakers 
does bring into question whether digited tetrapodomorphs even produced the 
Zachełmie trackways. Digit-bearing molds are preserved alongside continuous 
trackways but the ‘digits’ themselves are known only from isolated prints. 
Crown-group coelacanths, lungfishes, and tetrapods are known to engage in 
trotting gaits [33]–[35], and thus suggest substrate-based locomotor abilities 
in stem-tetrapods as well. Moreover, recent work [36] has shown that African 
lungfish using a bipedal pelvic-driven gait can produce the three trackways 
patterns known from the Zachełmie Quarry: (1) alternating doublets; (2) 
alternating singlets; and (3) opposite, ladder-like prints. Considering this 
range of potential explanations, the non-congruence of continuous digited 
prints with trackways patterns, and the increasingly strong stratophylogenetic 
congruence in the stem-tetrapod body fossil record, it might be wis!
e to approach questions about timing of origins with a pluralistic eye and a 
bit of additional skepticism."

33: Fricke H, Reinicke O, Hofer H, Nachtigall W (1987) Locomotion of the 
coelacanth *Latimeria chalumnae* in its natural environment. Nature 329: 
331–333.
34: Greenwood PH (1986) The natural history of African lungfishes. Journal of 
Morphology Supplement 1: 163–179.
35: Edwards JL (1977) The evolution of terrestrial locomotion. In: Hecht MK, 
Goody PC, Hecht BM, editors. Major Patterns in Vertebrate Evolution. New York: 
Plenum. pp. 553–576.
36: King HM, Shubin NH, Coates MI, Hale ME (2011) Behavioral evidence for the 
evolution of walking and bounding before terrestriality in sarcopterygian 
fishes. Proceedings of the National Academy of Sciences of the United States of 
America 108: 21146–21151.

I'll have to download ref. 36... oh, hey, it's open access, or at least the 
HTML version is. PDF of text + supplementary information with links to movies 
of bipedally walking/running and hopping African lungfish: 
http://www.pnas.org/content/108/52/21146.full.pdf+html?with-ds=yes