Friday mystery object #298

This week it’s back to bones. I’ve had a couple of very helpful work experience students photographing some specimens from the Dead Zoo comparative osteology collection and here’s a distinctive bone for you to identify. The Order should be easy, the Family simple enough, but the Genus and Species may prove more difficult:

mystery298

So if you think you know what this is please put your suggestions in the comments below. Have fun!

Friday mystery object #292 answer(ish)

Last week I gave you a final mystery object from the Grant Museum of Zoology to help me identify:

dsc06030

Part of the reason for that was because I knew I’d be starting my new job in Dublin where there is a great collection of comparative bird osteology that I thought I’d get a chance to look at in time to write this post.

Alas, I’ve had a whirlwind first week at Dublin’s Dead Zoo and although I’ve managed to take a look at a few sterna, I’ve not had much time to really think about them or consider the identification. I’ve also had limited opportunity to follow up on everyone’s very useful suggestions, although I have tried to use them as a guide to narrow down my perusal of the comparative collections.

However, I did get a chance to take some quick snaps of a range of bird sterna with my phone, so I’m going to provide you with a veritable feast of breast bones to compare the mystery specimen against:

You can click on each image to see a large version – hopefully this will prove useful for future identifications!

None of them quite match the combination of having perforations near the straight and truncated bottom of the mystery specimen, which sports a broad triangular flattening of the lower portion of the carina or keel. This may be a feature of the particular individual, or it might be diagnostic – herein lie the problem with using strongly functional features for identification, as a juvenile or zoo specimen may have differences due to developmental progress of lack of use of a feature. To illustrate, this keel from a Griffon Vulture from the Royal Zoological Society of Ireland shows a significant asymmetry (although it’s hard to see the deformation in the image due to the shadow – I’ll see if I can get a better image):

Griffon Vulture sternum

Griffon Vulture sternum

It’s also worth noting that the Grant specimen has had the top of the sternum cut off, so the overall shape is a little misleading. From comparing the sterna of a variety of bird groups I’m in agreement with the emerging group consensus that this is probably from a pretty large bird of prey.

Thanks for your input on this – I will check some more next week when I have a zooarchaeologist looking at the comparative bird collection and I’ll get the chance to dig out some more material.

Cheers!

Friday mystery object #286 answer

Last week I gave you this mystery object to identify, found on a beach in Ireland:

mystery286

It led to a lot of great cryptic comments relating to marine birds and sternum keels, but Lena was the first to comment and was spot on with the species (or at least as far as I can tell!)

Bird sterna are quite distinctive, with overall shape giving an indicator of mode of life. Long narrow but well-developed keels like this tend to be seen in marine birds that use their wings to fly underwater. The shape of the bottom and sides of the sternum tend to be quite specific to particular genera and species, making sterna pretty good for identification.

Of course that depends on having good comparative material and I was delighted to find John Rochester’s very helpful Flickr page, that has a comparison of British Auks (in this case we’re talking about the geographical British Isles rather than the sociopolitical concept of Britain).

If you take a look at those images you’ll notice that one fits the shape very well indeed – the Guillemot or Common Murre Uria aalge (Pontoppidan, 1763).

1024px-common_murre_rwd2

Guillemot with its meat and feathers on. Image by Dick Daniels, 2011

So that’s the identification I gave to Emer, Ronan, Rory and Paddy who found it on their hols!

 

Friday mystery object #285 answer

Last week I gave you this unassuming bit of bone, that I found with no identification in the Grant Museum of Zoology stores:

mystery285

Daniel Jones and Daniel Calleri identified the element as a radius, but beyond that there was a general feeling that identification of species was a bit on the tricky side. Palfreyman1414 pointed out that it’s something approximately human sized, with Lena ruling out an ungulate, suggesting that it could be from a carnivore or possibly a marsupial.

I must admit that my mind immediately went to carnivores and I initially thought it could be from a Black Bear, since it’s fairly robust and about the right length. However, after checking the ever helpful Adams & Crabtree book I realised that bears are even more chunky than this.

It didn’t look right for a dog since they are straighter, have a flatter profile and a narrower distal end. However, it did look right for a big cat and I’m fairly certain that it’s from a Leopard Panther pardus (Linnaeus, 1758). If you want to compare a Leopard with a Dog radius you can see them compared in this paper, along with a good description of the bones of the Leopard forearm.

A bit of a tricky challenge – so next time I may try to do something a bit more distinctive!

Friday mystery object #283 answer

Last week I gave you this zoomed in picture of a specimen to have a go at identifying:

mystery283

It was a bit tricky, so I also gave you this bonus clue to help:

mystery283_bonus

I was impressed to see that, despite the limited information available from the images provided, many of you managed to work out that this shows the lightweight ‘honeycomb’ structure that supports the casque of a hornbill.

That was the first challenge but, as ever, I was keen to see if you could get the identification to species – far more of a challenge considering the lack of a side view of the skull and lack of a scale. To make up for that I’ve decided to provide the necessary image here:

Ceratogymna atrata skull

I won’t say what species this is in this post, as I normally would, just to give some more of you a chance to make the identification yourself. However, what I will say is that the very first response by Wood contained a link to an image of the correct species and later to a blogpost featuring this very specimen. In that post there is a discussion about the appearance of the casque, with speculation about whether it had been damaged during preparation, resulting in its appearance. However, as Richard Lawrence pointed out, this appearance is actually normal for the skulls of several species of hornbill.

I will also say that the discussion between Daniel Calleri & Dan Jones and Richard Lawrence about whether it was a hornbill from a genus starting with A or B was interesting and I initially thought it was an A, but am now convinced that it’s a C.

If you’re desperate to know which species it’s from, here’s a link to the skullsite.com page about it.