My OperaAnother Feathered Dinosaur
Wednesday, July 4, 2012 1:46:32 PM
A newly found fossil of Sciurumimus albersdoerferi, which lived about 150 million years ago, provides the first evidence of feathered theropod dinosaurs that are not closely related to birds. The fossil is described in a paper published online on 2 July in the Proceedings of the National Academy of Sciences (PNAS). Because the new species sits deep within the evolutionary tree of theropods, the findings suggest that all predatory dinosaurs might have had feathers. In other words feathered dinosaurs might have been much more common than we thought. Down may also have been a special way of protecting baby dinosaurs. This may explain why they have not been found on adults.
This baby Sciurumimus, just about 70 cm long, was found in the limestones of northern Bavaria and preserves remains of a filamentous plumage, indicating that the whole body was covered with feathers. The genus name of Sciurumimus albersdoerferi refers to the scientific name of the tree squirrels, Sciurus, and means “squirrel-mimic”—referring to the especially bushy tail of the animal. The species name honors the two private collectors who made the specimen available for scientific study, Raimund og Birgit Albersdörfer.
The specimen of Sciurumimus is the most complete megalosauroid yet discovered and helps clarify significant anatomical details of this important basal theropod clade, such as the complete absence of the fourth finger.
Reference:
O. Rauhut et al. (2012)
Exceptionally preserved juvenile megalosauroid theropod dinosaur with filamentous integument from the Late Jurassic of Germany.
PNAS, published online 2 July 2012 (see abstract)
DOI:10.1073/pnas.1203238109
In Norwegian:
http://www.forskning.no/artikler/2012/juli/327055
This baby Sciurumimus, just about 70 cm long, was found in the limestones of northern Bavaria and preserves remains of a filamentous plumage, indicating that the whole body was covered with feathers. The genus name of Sciurumimus albersdoerferi refers to the scientific name of the tree squirrels, Sciurus, and means “squirrel-mimic”—referring to the especially bushy tail of the animal. The species name honors the two private collectors who made the specimen available for scientific study, Raimund og Birgit Albersdörfer.
The specimen of Sciurumimus is the most complete megalosauroid yet discovered and helps clarify significant anatomical details of this important basal theropod clade, such as the complete absence of the fourth finger.
Reference:
O. Rauhut et al. (2012)
Exceptionally preserved juvenile megalosauroid theropod dinosaur with filamentous integument from the Late Jurassic of Germany.
PNAS, published online 2 July 2012 (see abstract)
DOI:10.1073/pnas.1203238109
- http://www.pnas.org/content/early/2012/06/25/1203238109
- http://www.science20.com/news_articles/sciurumimus_albersdoerferi_dinosaur_feathered_theropod_not_related_birds-91672
- http://www.amnh.org/news/2012/07/newly-discovered-dinosaur-implies-greater-prevalence-of-feathers/
In Norwegian:
http://www.forskning.no/artikler/2012/juli/327055
simoncito # Friday, July 6, 2012 8:17:21 AM
A friend of mine had maintained that feathers in dinosaurs only appear up to a certain size, and that species that grew to be larger than two or three meters (or a corresponding body mass) lost their feathers at that stage. That made sense to me, given that the body surface/body mass ratio makes insulation less and less important or even detrimental at a certain point, but then they came across yutyrannus huali http://www.nytimes.com/2012/04/05/science/dinosaur-dig-in-china-turns-up-largest-known-feathered-animal.html which was not a small or immature theropod and still had feathers. And one asks: What for?
Well, bird have feathers not just for insulation, but also for signaling to potential mates and so on, so maybe that's the answer. I do wonder though ...
Ole Nielsennielsol # Saturday, July 7, 2012 9:08:44 AM