Is It a Bird or a Dinosaur? A Tale of a Tail Trapped in Amber


At the tail end* of last year, the discovery of “Eva” (more formally known as DIP-V-15103) was announced as a dinosaur tail with feathers preserved in Cretaceous amber. The apricot sized sample also includes an ant and some plant debris.

Discovered in an amber market in Myanmar, the tail fragment is believed to be a coleurosaur.  Coelurasauria (“hollow tailed lizards”) is one of two clades of the new Avetherapoda (literally “bird dinosaur”) clade, which also includes the Carnosauria clade. Coelurasauria basically includes all the theropods that evolutionists believe are more closely related to birds than carnosaurs, including includes compsognathids, tyrannosaurs, ornithomimosaurs, and maniraptorans (the clade which includes birds and the coelurasaurs that evolutionists believe are most closely related to them). So from the evolutionists POV, since it’s a dinosaur with feathers, what else would it be but a coleurosaur, right? 

The study itself is more scientific  (that is to say, tentative) than the reports we’ve read in National Geographic and other news sources. Which is to say there is a bit of misinformation surrounding the unusual find. For example, most of the news sources make a big deal out of the fact that there is no evidence that the vertebrae were fused into a solid rod at the tip of the tail, but then again this vertebral segment is believed to be from the middle of the tail, so we really have no idea whether the tip of the tail was fused or not. On the other hand, the projected length of the tail (estimated at 15 to 25 vertebrae) and the shape of the vertebrae suggest a flexible tail; the actual length of the fragment is 3.7 cm long, containing 8 vertebrae, each the size of a grain of rice. Archaeopteryx has a long tail with vertebrae fused at the ends, although not in the “parson’s nose” or pygostyle configuration of modern birds. It is still considered a true birds.

Much ado has been made of the fact that, while the evenly spaced barbules of the feathers were already well-developed, the rachis  (central shaft of the feather) is short and weak; however, there is little evidence of muscles on the specimen. This might suggest that the tail was light as in birds like Archaeopteryx rather than heavily muscled as in the tails of theropods dinosaurs, a difference that would be important in judging whether they carried themselves from the hip (as in dinosaurs with heavily muscled tails) or the knee (as in birds).

This means that the evidence for Eva being a bird or theropods is still pretty much in the air. Not that the specimen likely flew with that short rachis; it might have glided. Either way, those feathers are true feathers, not protofeather fuzz, meaning that in all likelihood it was a bird.

The bottom line is that nothing in this specimen suggests dinosaurs-to-birds evolution except to someone convinced of common descent. The barbs and barbules of the feathers are already fully formed and complex and the rachis presented in photographs seems well developed despite claims to the contrary. I believe my fellow creationists are justified in naming Eva a probable bird rather than a dinosaur.



*I can’t resist a bad pun

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