You heard it here first: No two Archaeopteryx look the same.

The science section
of the online British news outlet, the Guardian, reported on the 12th (Haarlem) specimen of Archaeopteryx re-named Ostromia. You can read that story online here.

From the Guardian article:
“Of the Twelve Specimens Once Known as Archaeopteryx (SPOKA), only nine continue to carry that name. At the end of the day, we can’t all be winners. But even within that group of nine specimens, no two Archaeopteryx look the same. Rauhut and colleagues report that there is significant variation in the size, shape, spacing and orientation of the teeth, as well as differences in body size between the different specimens. This could be an ontogenetic pattern, with larger individuals representing adults with more developed dentition. Alternatively, as the Solnhofen Basin constituted a tropical island archipelago during the Late Jurassic, these differences in body size and dentition could be interpreted as island adaptations. Similarly to today’s Galápagos finches, different populations of Archaeopteryx may have adapted to different insular environments.”

We looked at
Solnhofen birds (Fig. 1) earlier here and Ostromia here. Since 2015 readers have known that no two Archaeopteryx specimens were identical and that phylogenetic analysis split them apart to nest at the base of each one of all the Cretaceous bird clades. And yes, we know of an embryo archaeopterygid, the Liaoning embryo most closely related to the London specimen.

Figure 3. Several Solnhofen birds, including Archaeopteryx, compared to Ostromia to scale.

Figure 3. Several Solnhofen birds, including Archaeopteryx, compared to Ostromia to scale.

It really is time to
run these birds through analysis and either affirm, modify or invalidate the results of the large reptile tree. And it should be done by someone with firsthand access to all the specimens. That would be a good test.

References
Elzanowski, A., 2002. Archaeopterygidae (Upper Jurassic of Germany) In: Chiappe LM, Witmer LM, eds. Mesozoic Birds. Above the Heads of Dinosaurs. Berkeley: University of California Press. 129-159.
Foth C, Rauhut OWM. 2017. Re-evaluation of the Haarlem Archaeopteryx and the radiation of maniraptoran theropod dinosaurs. BMC Evolutionary Biology 17:236

https://www.theguardian.com/science/2018/feb/21/the-new-specimen-forcing-a-radical-rethink-of-archaeopteryx

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