STL Science Center

STL Science Center

28 November 2018

It's in the Name

It was mentioned earlier this week that Protarchaeopteryx, as a name, translates literally to "Before Archaeopteryx". This poses a small problem because Protarchaeopteryx is a Cretaceous archaeopterygian and Archaeopteryx itself is a Jurassic animal. Geologically speaking, Archaeopteryx predates Protarchaeopteryx by approximately 25MY; though it is important to note that the accepted span of existence for Archaeopteryx is 150MYA - 125.45MYA and Protarchaeopteryx shows up in the fossil record at 124.6MYA. This means that they are not, temporally, that distant from one another. This does not necessarily reflect their phylogenetic relationship to one another. Now, the reason that we brought up the names is that the implication of the name is not actually what the name means. What I mean, and what Ji and Ji meant by that in 1997, is that Protarchaeopteryx did not come before Archaeopteryx, but rather it possess characters which appear to place it in a phylogenetically primitive position in relation to Archaeopteryx. The justification for the name as assigned by Ji and Ji was that "...it [Protarchaeopteryx] is regarded as more primitive because it has a more elongated tail, more robust pelvic girdle, longer and larger hind limb, and unfused proximal metatarsals [than Archaeopteryx]." These characters, it may not require stipulating, are more derived in Archaeopteryx. To better understand the description and read the translated version of that 1997 paper, please see the reference presented below.

Reference:
Ji, Qiang, Shu’an Ji, and Translated By Will Downs. "A Chinese archaeopterygian, Protarchaeopteryx gen. nov." Geol Sci Tech 238 (1997): 38-41.

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