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| According to a recent study, Archaeopteryx had some of its feathers jet-black, as discovered by its preserved melanosomes. |
Image written for permission to the author Nobu Tamura. Image courtesy of Nobu Tamura, whose blog is here and site here.
Based off of an Archaeopteryx feather, researchers were able to report upon the discovery of preserved melanosomes: cell organelles containing a pigment called melanin which, based upon morphology and a comparison to modern animals, can tell what an ancient organism's colors were. For example, the archaeopterygid/troodontid Anchiornis huxleyi has had its colors deciphered, as well as Sinosauropteryx - the basal coelurosaur.
Comparisons between modern bird melanosomes and the Archaeopteryx feather found that these were most morphologically similar to that of a blackish pigment. There is a small 5% chance that the feather, in life, was actually not black, but a different pigment.
Did this feather really belong to Archaeopteryx?
Melanosomes preserved in the original holotype specimen of Archaeopteryx have been discovered. However, this feather has been replaced with the London specimen neotype, discovered in 1861 (as was the feather, but it was discovered first and it was announced the holotype for a new species) and was the first Archie skeleton to have been unearthed.
What was the need for replacement? The feather only holds so much data to categorize complete other osteological specimens under that same taxon. In fact, scientists were not even quite sure that these skeletons belonged to A. lithographica (the feather), making the zoological nomenclature inefficient, hence the neotype.
If uncertainty regarded the feather's classification as belonging to the same species as the skeletons, there can still be some doubt that the feather analyzed actually did belong to what we would recognize as Archaeopteryx. Meaning that Archie may have been as pale as a dove, or as black as charcoal.
* If you think about it, every species is a transitional between one species and another. It would be silly to think that one species formed a new clade just like that. It takes many generations to create a new clade based off of morphological differences in multiple species.
Abstract - Archaeopteryx has been regarded as an icon of evolution ever since its discovery from the Late Jurassic limestone deposits of Solnhofen, Germany in 1861. Here we report the first evidence of colour from Archaeopteryx based on fossilized colour-imparting melanosomes discovered in this isolated feather specimen. Using a phylogenetically diverse database of extant bird feathers, statistical analysis of melanosome morphology predicts that the original colour of this Archaeopteryx feather was black, with 95% probability. Furthermore, reexamination of the feather's morphology leads us to interpret it as an upper major primary covert, contrary to previous interpretations. Additional findings reveal that the specimen is preserved as an organosulphur residue, and that barbule microstructure identical to that of modern bird feathers had evolved as early as the Jurassic. As in extant birds, the extensive melanization would have provided structural advantages to the Archaeopteryx wing feather during this early evolutionary stage of dinosaur flight.
Reference - Ryan M. Carney, Jakob Vinther, Matthew D. Shawkey, Liliana D'Alba, Jörg Ackermann (2012). "New evidence on the colour and nature of the isolated Archaeopteryx feather". Nature Communications, 3: 637. doi: 10.1038/ncomms1642.
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