This week I have my last mystery object from the Grant Museum of Zoology, since I am starting my new job as Assistant Keeper of Natural History at the National Museum of Ireland next week. However, there is one specimen that’s been getting on my nerves the whole time I’ve worked at the Grant, as it says on its label that it’s from an Albatross, but I simply don’t believe it. Can you help me work out what this rather dusty specimen actually comes from?:
No need for cryptic clues I think, since it’s probably going to be a little bit of a challenge and some discussion seems likely – which will be easier if we all know we’re talking about the same thing.
Have fun with this one!
Zygoma 
Definitely an upside-down keel with articulating rib. Also, definitely NOT and albatross which has an extremely well developed sternal crest.
Reminiscent of a Cape Griffon (I’m in South Africa), albeit the specimen is wider with smaller posterior lateral foramena. Also, the sternal cresting starts much lower with heavy muscle scarring leading in which would suggest a stronger pectoral muscle and thus lifting capacity.
Very interesting! Look forward to seeing the outcome!
Since I know diddley about these things, may I ask why it is upside-down? Seriously it would help me to know. Ta.
Wow – look at that heavy breastbone! After Thanksgiving turkey, it did look very familiar, lol. It seems too massive for such a glider as the albatross, the first thing that popped into my head actually was a dodo, but the breastbone is upside-down for that. I looked everywhere for a skua skeleton, thinking that might fit – a strong, heavy bird that needed lots of lift (to steal food) but I couldn’t find one anywhere – there is some literature about the skua skeletons, but I wasn’t good enough to find any photos. So, in absence of any proof, I will have to hazard a guess – a south polar skua – or, just to be silly, an upside down dodo. 🙂
How deep is the keel? This website is pretty helpful: http://www.shearwater.nl/index.php?file=kop125.php
here’s a great resource for sea birds that i’ve used before, though it doesn’t have the best views of skua keels.
http://www.shearwater.nl/index.php?file=kop125.php
It’s not from an albatross. The size is about right but the shape is wrong. Albatross only have 5 costal facets for the ribs . This has more . Albatross also don’t have those twin apertures. That is more of a raptor trait. The shape is very close to being from a North American golden eagle but the size is just a little small . I’d be looking at an eagle a bit smaller than North American eagles. A side view would help but probably not for me . What intrigues me even more is the stand it is on , and what looks like an extra wing bone between the coracoid and the humerus . The ruler is hiding that connection but the humerus would fit into the distal end of the coracoid and the humerus is a very long stong bone . The bones have been sliced , presumably to show the internal struts but someone did a lot of work to show that and then kind of crudely wired it to the wood-work . All very interesting. Like an exhibit for a science fair by someone who had a father who was a decent woodworker who made the stand . Not really display quality work for a museum. Maybe for a classroom . .
I agree with Lee Post – looks like a raptor sternum. The much-missed blog, Jake’s Bones, has a buzzard sternum bearing remarkable similarities to this one, except it is about twice the size (one dimensionally, I’ve about eight times the volume/mass).
Do smaller raptors also have similar apertures at their bases?
I’m seeing a trend here: one of the cathartids, perhaps a condor? The carina seems to be very small in this view, and there’s that expanded are at the posterior margin.
Oh dear. And here I was getting certain it was one of the accipitredae. Was sure it wasn’t one of the New World raptors. But then you came along…
I’m getting about 10 cm long on this sternum. . That’s about 2 cm too small to be a north american eagle . Which is also way too small for a california condor 15-16 cm range and slightly too big for a black or turkey vulture (8-9 cm range ) and way too big for a red tailed hawk . The apertures seem to be hit or miss as to which species of raptors have them or not .
Ah. Makes sense.
I am counting it as 12 cm, and am particularly intrigued by the triangular “shield” at the base which very few birds seem to have.
The wing length seems to indicate a soarer, either raptorial or over water. But no seabirds seem to have anything akin to those apertures (are we allowed to call them fenestres?) Penguins, I think, for instance, have posterior notches, not holes.
So I am still sniffing towards a medium sized Old World hunter. Secretary Bird anyone?
Not really a sea bird but mergansers have those holes as well .The shape and size doesn’t match too well . The golden eagle has that triangular plate that merges into the keel to a similar degree. How are you getting 12 CM ? Maybe I can up the length of it . That arm that extends off the top right side of the sternum is a seperate bone. Just making sure that isn’t what you included in the length. I just measured a goshawk sternum at 9.5 cm long . It too had the apertures. ( but not quite the right shape )
See? This is what happens when I speak to people who know so much more than me. I learn stuff. It’s disgusting!
More seriously, if that triangular shield is a feature of some of the larger raptors, could a bone like this have ossified this far even in a smaller juvenile? Could we be looking at a young ‘un?
After all, even Paolo admits to frustration at not knowing precisely what this is.
Is it possibly a vulture that would be sorted into Harry Potter’s house at Hogwarts?