Oops 090628

[p 20, col 2, §3]

Genetic analysis, in relation to evolutionary issues, shows that actually, genes for limbs and for tails are similar, and many are identical ([98] and references above31, Ref. [60]). Also, genes which serve to form the true limb skeleton, are actually present in fish fins, in which such skeletal elements are absent [98] (Fig. 21).

31 “Not only are the same Hox genes expressed in both developing appendages but they are expressed in identical spatial and temporal patterns” in reference [85].


[98] is An autopodial-like pattern of Hox expression in the fins of a basal actinopterygian fish, Marcus C. Davis, Randall D. Dahn & Neil H. Shubin, Nature 447, 473-476 (24 May 2007) | doi:10.1038/nature05838 and deals with autopodial-like gene expression pattern, not limb in general. [for fig 21 follow the link].

[60] is Hox genes in digit development and evolution, József Zákány & Denis Duboule, Cell Tissue Res (1999) 296:19–25, doi: 10.1007/s004410051262.

[85] is presented as “85. D. Shu, X.-L. Zhang, S.C. Morris Nature (1996)“, probably corresponding to A Pikaia-like chordate from the Lower Cambrian of China, D.-G. Shu, S. Conway Morris, X.-L. Zhang, Nature 384, 157-158 (14 November 1996) doi:10.1038/384157a0, the authors not being presented in the right order. It is their single common paper published in Nature in 1996 and one of the four common (with other co-authors) ever published in Nature, all presenting fossils. At least, some paleontology slipped in this subsection, mistakenly, but…

Citation 31 is from [93], Why we have (only) five fingers per hand: Hox genes and the evolution of paired limbs, Clifford J. Tabin, Development 116, 289-296 (1992):

Not only are the same Hox genes expressed in both developing appendages but they are expressed in identical spatial and temporal patterns. The expression of posterior genes in the anterior appendage thus may indicate that the pelvic and pectoral fins evolved by both adopting molecular mechanisms present in a common ancestral posterior fin.

Oh boy! What a mess!

Now, many genes must be commonly expressed at tails and limbs and some differentially expressed specifying features identity.
What’s the point Fleury is trying to make?


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