They have a head! Cretaceous dino head in Burmese amber

[ITdactyl]

https://www.nationalgeographic.com/science/2020/03/smallest-ever-fossil-dinosaur-found-trapped-in-amber/

https://www.sciencemag.org/news/2020/03/head-tiny-dinosaur-found-trapped-amber

https://www.scientificamerican.com/article/smallest-known-dinosaur-found-in-amber/




Oculudentavis khaungraae - apparently closer to urvogel than to a modern pigeon... and hummingbird sized to boot.

[Faelrin]

I was a wee bit too excited jumping to conclusions thinking it was going to be something without a beak, but regardless this is still an amazing find, since this is still the first time seeing a toothy birb in the flesh (well the head anyways). Definitely up there with the tail, wings, etc so far on best amber discoveries I think. Pretty interesting how tiny it is too. Those deposits just keep on giving at this rate. Thank you, you magnificent prehistoric trees and your precious sap capturing and preserving some unfortunate victims for millennia, that have luckily survived in tact (somewhat) for all these millions of years, for us to uncover and study.

[Sim]

My understanding is a beak won't be present on a part of the mouth that has teeth, which is explained here: http://dinogoss.blogspot.com/2011/04/youre-doing-it-wrong-birds-with-teeth.html

So this new bird's snout wasn't a beak along most or all of its length.  I'm surprised it was reconstructed without lips, I'm not sure if that's what the fossil shows.  An interesting thing about it is it shows the feathering didn't continue further down the snout.

[stargatedalek]

My understanding is a beak won't be present on a part of the mouth that has teeth, which is explained here: http://dinogoss.blogspot.com/2011/04/youre-doing-it-wrong-birds-with-teeth.html

So this new bird's snout wasn't a beak along most or all of its length.  I'm surprised it was reconstructed without lips, I'm not sure if that's what the fossil shows.  An interesting thing about it is it shows the feathering didn't continue further down the snout.

The phrasing of that is rather deceptive. What that post is referring to as "beak" is inherently semantic. These animals still had a hard keratinous coating on the outside of their jaws, but the inside would have been soft with traditional gums. The beak in birds covers the area that would normally be gums with keratin as well, hence the argument of when it starts being a beak.

All of this conveniently ignoring that we refer to turtles, puffer fish, and marine parrot fish as having beaks. Given that it feels incredibly disingenuous to refer to the "keratinous mouth parts" of dinosaurs and early birds as anything but beaks. It absolutely gives people the impression they should be depicted with scaled snouts, which we know is incorrect.

[brontosauruschuck]

This guy (or gal) is so cute! I hate imagining it slowly suffocating in sap.

[Patrx]

As with any cool dinosaur discovery, it's always worth reading the Tetrapod Zoology article on the subject!

[Sim]

Well, turtles do have a beak.  I'm surprised pufferfish and parrotfish would be referred to as having beaks though, as the feature is composed of the animals' teeth.  This makes me think of how there are whales and dolphins that are said to have a beak.  In the case of the fish and the cetaceans I personally think it's a misnomer to say they have a beak, although I can see the use in colloquial speaking for the cetaceans.

How is it known a scaled snout is incorrect?

Thanks for the link @Patrx!  I noticed the following in that link:

It also has to be said that the teeth look prominent, such that it's hard to understand how they could be sheathed by lip tissue, nor is any such tissue preserved. Remember that beak tissue doesn't occur in the same part of the jaws as teeth do, so Oculudentavis wouldn't had have a true horny covering on its jaws. I assume that it had 'lip' tissue sheathing its teeth (except perhaps for the tips of the longest ones), as do other terrestrial tetrapods.

[Patrx]

Exactly! That portion of the text is the most specifically interesting to me. It sounds like there must have been something covering the teeth, but the remains don't show us precisely what that looked like. The teeth themselves, as described earlier in the article, are unusual in a couple of ways, so I wonder how illustrative its facial tissues will really be with regard to trying to reconstruct other theropods.

[Sim]

It turns out Oculudentavis might not be a theropod: http://theropoddatabase.blogspot.com/2020/03/oculudentavis-is-not-theropod.html

[ITdactyl]

Oh well, that's science I guess... discovery... disputes... discovery... disputes... after 3 decades, facts... disputes..

Also this:
http://markwitton-com.blogspot.com/2020/03/the-ugly-truth-behind-oculudentavis.html

I know we're discouraged from getting political in the forum.. but I'm glad Mark Witton (among others) talked about the elephant in the room.  I'll admit to still celebrating this find, despite its (possibly) dark provenance.  I think the best way is to raise awareness, so that the situation may be changed in the future.

[stargatedalek]

As much as they may sell for these fossils are barely a novelty to the people doing this stuff. These mines are for the jewelry industry, a demand for fossil specimens alone, even at the described prices, is a drop in the bucket and would not on its own be creating these conflicts.

The idea that research on these specimens should be banned or even protested feels not only like an overreaction but a placement of blame in the wrong place.

[Ravonium]

Pretty big update to this discovery: https://www.nature.com/articles/s41586-020-2553-9

[Libraraptor]

Didn't some scientists doubt that the specimen was even a dinosaur at all?

[CityRaptor]

Yep. Some serious scientists...and David Peters. No doubt being right about that one ( by pure chance ) will go straight to his head.

[ceratopsian]

At least Peters wasn't the only one to express doubts!

[Halichoeres]

I don't think Peters would concede this, but this is a case study in science working like it should. I don't mean the initial paper, it seems like at least one of the original authors knew it was incorrect and published it anyway, and I think it also reflects editorial and peer-review failures. Maybe you can quibble with the retraction as a logistical matter, but the collective response of identifying the problem, correcting the record, and changing opinions in response to new evidence is exactly what's supposed to happen. Peters hasn't shown the same willingness to revise his opinions in the face of new data, to put it mildly.

[ceratopsian]

You make a cogent point on Peters.  He is indeed utterly intransigent.

[brontosauruschuck]

You make a cogent point on Peters.  He is indeed utterly intransigent.

Thank you for teaching me a new word.