Well, “new” is perhaps not the best word, since the astonishing find was made some year ago, but the paper was published recently. I have not accessed the paper, but made some basic research over the internet, after seeing a post on Paleoexhibit. This dinosaur, a juvenile megalosaur called Sciurumimus albersdoerferi (new genus and species, or, as scientists would say, gen. et sp. nov.), from the Late Jurassic period, is a fantastic discovery, not as much because it is the most well-preserved theropod found in Europe, but because it had feathers!
Image from http://www.globochannel.com/wordpress/2012/07/03/fossile-piumato-riscrive-la-storia-dei-dinosauri/. Apparently, the feathers are supposed to be visible under ultra-violet light.
Feathered dinosaurs are found virtually all the time in these days, especially in Asia and South America, but they are always closely related to early birds. Sciurumimus is indeed a theropod, the major group of dinosaurs from which birds evolved, but it is a megalosaur, a much more primitive member of the thropod group. Thus, this discovery shows that feathers appeared much earlier than in bird-like dinosaurs.
From what I have read, it seems the main emphasis of the importance of this find is that it (a) suggests that most theropods had feathers, and (b) “shows just how deep in the family tree many characteristics of modern birds go, and just how bird-like these animals were” (a web article about Sciurumimus, quoting Mark A. Norell; http://www.science20.com/news_articles/sciurumimus_albersdoerferi_dinosaur_feathered_theropod_not_related_birds-91672).
I have no disagreement with this – on the contrary, I have a thought that favours (a), and I suppose (b) too, depending on how you see it… Although Sciurumimus is a basal theropod, it lived around the time of the evolution of modern birds (give or take a dozens of millions of years… I don’t know exactly), i.e. when the coelurosaurs, the theropod lineage that gave rise to birds, had invented flight feathers. Now, if two separate groups share a common feature, it is a good reason to suspect that the most recent common ancestor of those groups also possessed that feature. Then, it would imply that feathers are older than known even now, that we can expect to find even older feathered dinosaurs!
Also, if the presence of feathers is such a basic feature among theropods, it might be a feature shared by other groups linked to the same ancestry. For instance, maybe allosaurs and other large Jurassic theropods had feathers too.
Still, there seems to be little though around what this actually could mean. The discovery shows that most theropod dinosaurs probably had feathers, And what does that mean? What are feathers used for? There are many things, not just flight. They can also be flashy and brightly coloured to serve as display or communication structures, or downy to function as insulation, making the body lose (and gain) heat slower. However, these are all linked to one of the most intriguing questions about dinosaurs: in essentially any of these ways, feathers are connected to warm-bloodedness!
Personally, I find the debate about whether dinosaurs were warm-blooded or not completely mesmerizing. I would love to explain how feathers fit into this, but it would take very very long. However, for a dinosaur course last summer, I wrote an assignment on this question. My analysis was eleven pages long (1.5 spacing), so you see why I do not want to go too deep here. Yet, I might upload the text as well, for those who are interested!
If you read that, it would be terrific, but if not, just trust me, as a fanatical dinosaur-warm-bloodedness-maniac-and-nerd, when I say that this find could turn out to be very important evidence in the matter, as it suggests that feathers, and thus warm-bloodedness, “goes deep” within the theropod group, and therefore is not restricted to advanced carnivorous dinosaurs. I will definitely try to keep an eye out for more news, and try to learn that weird name!
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