Friday mystery object #262 answer

Last Friday I gave you this pretty characteristic mystery object from the Berlin Museum für Naturkunde to try your hand at identifying:

mystery262

There were lots of great comments – I must apologise for not responding to many (and for posting the answer to this mystery object so late), my excuse is that I’ve had an insanely busy week finishing up my old job at the Horniman Museum and Gardens and then getting started in my new job at the fantastic Grant Museum of Zoology at University College London (more to come about my big move). I also got started on a really interesting project looking at Gorilla osteology and I’m feverishly trying to prepare a training workshop on identifying natural materials for next week.

Back to the object. Several of you noticed the presence of a baculum (or penis bone) which shows us quite definitively that this was a male animal.

Panda penis bone (baculum) from the Berlin Museum für Naturkunde

It also suggests that the specimen was prepared and mounted without the prudishness that many historical mounts were affected by (see Jack Ashby’s comments about this in his post on the Grant Muesum’s Ringtail).

Many of you also correctly recognised that the plantigrade (or flat-footed) posture, short tail and robust build suggested a bear of some sort.

Panda hind limb bones showing plantigrade foot

The distinctive sagittal crest was the final feature needed for identification for some of you to work out that this is the skeleton of a Giant Panda Ailuropoda melanoleuca (David, 1869).

Panda skull side view

Panda_skull_top

I tend to think of Panda skulls as looking like a cross between those of a Hyaena and a Gorilla, which makes sense when you consider the adaptations of the jaw musculature required for the Panda to process the large volumes of tough bamboo needed to provide enough energy for survival. The bone of the skull has to be able to manage the large forces produced by all this chewing, resulting in a big and robust sagittal crest, a thick and deep mandible and really deep muscle scars on the coronoid process.

These are all features you also see in big chewers like the Gorilla and Hyaena, but not in rodents and ungulates – I think this reflects the difference between groups that rely on temporalis muscle (which runs along the side of the braincase) in chewing compared to the masseter muscle (which attaches to the zygomatic arch or cheekbone).

The final clue to confirm that this is a Giant Panda is the ‘thumb’ on the front limbs:

Panda_thumb_1

Panda_thumb_2

This handy (excuse the pun) extra ‘digit’ is actually the radial sesamoid bone of the Panda’s wrist, that has been commandeered by evolution for use as a bamboo holder. There are a few other species that have done weird things with wrist bones to gain a digit, but this is clearly not a Mole or Elephant and Red Pandas have a much longer tail.

I hope you enjoyed some of the interesting bony features of this specimen – it’s great to have a chance to see under the surface of such an iconic animal!

Friday mystery object #245 answer

Last Friday I gave you this guest mystery object from Dr Nick Crumpton at the NHM:
mystery245
Here’s what Nick had to say about it:
So when I first picked it up I thought – embarrassingly now – that perhaps it was something a bit pinniped-like but then the teeth didn’t match that idea at all so I reverted to thinking it was a bit more doggy.
Irritatingly, it was a juvenile so that scuppered size-based guesses, and ruled out taking too much information from the posterior, mandibular teeth. Also, the skull was darn cute, with a shorter snout than an adult would possess.
I had a couple of ideas from looking at the width of the zygomatic arches, but that lack of a parasagittal crest got me all twisted around. And time was tight for what we needed it for!
My esteemed colleague Mr Garrod was the first to push me in the direction of a wolverine, but I’ll leave it to Paolo to show how he managed to ID the little critter and save the day – although it looks like a bunch of people on here already managed that! Love the bone-banter. 😀
We’ve discussed in the past how the skulls of juvenile animals can be misleading and for this species a number of the features you would immediately recognise in the adult are absent in this juvenile. Therefore I’m not that surprised the suggestions in included Arctic Fox, Sea Otter, Common Seal and Spectacled Bear, in addition to the possibility of Wolverine.
Wolverine cranium

Wolverine cranium for comparison

Despite the juvenile dentition, the blade-like molar and 3rd premolar, and robust second molar were indicative of a carnivore with a specialisation for eating bone and the breadth across the zygomatic arches indicated something with a powerful bite force.
Wolverine dentition is remarkably robust, since they often scavenge bone and in the winter they need to feed on meat that has frozen solid. They have a wide skull (see above), but the relatively large upper molar is at right angles to the 4th premolar, which has a cleft that the 3rd premolar nestles into.
This is rather different to the much straighter dentition of the mystery animal, which is distinctly more cat-like, albeit with too many teeth. That narrows it down to one of the Hyenas. From there it becomes a bit more difficult and the fact it’s a juvenile throws a bit of a spanner in the works, but if pushed I’d probably opt for Spotted Hyaena Crocuta crocuta (Erxleben, 1777).
So well done to Chris, Lena, palfreyman1414, Allen Hazen and henstridgesj who all came to the same conclusion.
Finally, a big ‘thank you!’ to Nick for posing a decent challenge!