Today’s mystery object is a fairly straightforward one from the Grant Museum, although I’m hoping that we’ll get a species identification for the specimen. Any idea what this is?
As usual, a nice cryptic clue would be appreciated so that we can have some fun and not give away what it is too soon for those who are developing their identification skills. Enjoy!
This week I have a lovely, but perhaps an easy skull for you to identfy from the Grant Museum:
Cryptic clues on what you think this is please, let’s see what creative gems you can come up with!
Last week I gave you this part of a skull to have a go at identifying:
It’s quite a distinctive structure and very particular to one particular group of mammals. It is of course an external auditory meatus (or ear hole as it’s more commonly known), but instead of opening directly into the auditory bulla (the inflated bony bulb that holds the ear bones) it has a long and robust tube.
Lee Post, Daniel Calleri & Dan Jones and Allen Hazen recognised this characteristic feature as belonging to a Beaver and Richard Lawrence went one better and narrowed it down to Castor canadensis Kuhl, 1820 – an identification that I agree with having seen the whole skull:
I’m not sure if there’s any real functional reason for the ear tube, but it looks to me like it might be a “spandrel” a feature that’s an artefact of another adaptive feature – in this case the articulation of the mandible.
Gnawing through a tree trunk is no easy task, so it’s not surprising that the Beaver has some serious adaptations to deal with the work involved. Unlike carnivores, which have a fixed lateral mandibular articulation powered mainly by the temporalis muscles, rodents have a dorso-ventral articulation usually powered by the masseter muscles, which allows the jaw to move backward and forward. In the Beaver the sagittal crest suggests that the temporal muscles are more involved than usual which, with the orientation of the articulation, may necessitate the ear tubes as lateral braces against which the mandible can secondarily articulate. That’s my guess…
Great work on identifying this specimen using very limited information!
Sticking with a close-up theme, have you got any idea what this very distinctive bit of bone is from?
As usual, you can leave your suggestions, comments and questions below. If you find this too easy feel free to spice up your answer with some cryptic clues. Have fun!
Last week I gave you this zoomed in picture of a specimen to have a go at identifying:
It was a bit tricky, so I also gave you this bonus clue to help:
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:
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.
Last week I asked for your opinion on this mystery object:
It had originally been identified as Boa constrictor and then reidentified as Green Anaconda, but I didn’t believe either of those options.
There was some activity in the comments, from the initial observation that it’s a snake from Wood, to Andy Mills’ suggestion of Python, with palfreyman1414 and Daniel Jones and Daniel Calleri’s discussing how to tell whether it’s a boid or pythonid.
In fact, palfreyman1414 did some sterling work tracking down characteristics to help distinguish between these commonly confused groups, with this handy comment:
“The postfrontal bone, usually present, borders the orbit behind, rarely also above, and in the pythons a supraorbital bone is intercalated between it and the prefrontal bone.”
And..
“Boids are, however, distinguished from the pythons in that none has postfrontal bones or premaxillary teeth”
The character of the presence or absence of teeth in the premaxilla (the frontmost bone of the upper jaw in the midline of the skull) is particularly useful, although it’s not unusual for the premaxilla to fall out of snake skulls.
The postfrontal character is a bit less obvious and I’m not fully convinced by it – not because there isn’t an extra bone in the pythons compared to the boas (there is), it’s just whether it’s a postfrontal, a supraorbital or a post orbital. That depends on the reference you read. To help get an idea of the bits we’re talking about, I’ve highlighted them here (purple for premaxilla, pink for the bit missing in boids, call them what you like):
It’s probably worth mentioning that Anacondas are members of the boid family, so it’s clear that this specimen is a pythonid rather than a boid. But that doesn’t tell us what species it is (if you want to see a Boa constrictor skull there’s a video of one here).
Comparing overall skull shapes in snakes is not very effective, since the skull is very loosely articulated to allow it to deform when swallowing large prey, so when mounted they can be very variable in shape. Because of this you need to compare the shapes of the various bones that make up the skull to narrow it down.
There is a very helpful image resource called BioLib that has validated photos of skulls amongst other images, so it’s well worth checking out. Trawling through I didn’t manage to find a species with the same shapes in the nasals, prefrontals, frontals, parietals and supratemporal – but I did discover a specimen photo by Jean-Christophe Thiel that fit (not to mention a previous mystery object) – so I’m fairly confident that this is a Royal Python Python regius (Shaw, 1802).
Many thanks to everyone for their comments – it’s been a fun challenge where I know I’ve learned an awful lot. I hope you have too!
This week I have another specimen from the Grant Museum of Zoology for you to have a go at identifying:
This specimen has an identification, but I’m not sure I agree with it, so I want to see what you think it is.
Have fun with it!
Last week I gave you this crocodilian skull from the Grant Museum of Zoology to see if you had any thoughts about which species it might be:
It turns out that you did indeed have some excellent thoughts about the identification, with Cindy Nelson-Viljoen immediately getting it right, with astute observations from David Godfrey and palfreyman1414, plus another correct responses from Joe Vans (as well as Tone Hitchcock and Henry McGhie not via the comments section).
This is a skull of the Dwarf Crocodile Osteolaemus tetraspis Cope, 1861. It’s small size is the first clue, but given how crocodiles grow this could pass as the skull of a young individual of a much larger species. As David Godfrey pointed out, there may be some paedomorphism (where adults look like juveniles) in effect in this species, since the adults as well as being small, have relatively short snouts and big eyes – which are features of juvenile animals as you can see in this display of crocodile development I did for Dinosaurs! Monster Families just before leaving the Horniman:
Part of my reason for wanting to show you this specimen was to force myself to look for some good online resources to get more familiar with crocodilian morphology. As it turns out, I did find a very useful comparative image, which shows the size and shape of the mandibular foramen (a large gap between the bones in the side of the lower jaw) is a helpful feature:
In this species the foramen is small, which when considered with the overall proportion is quite distinctive. Of course, this image does not include all 24(ish) living crocodilian species, but it does provide a pretty good range. Hopefully this will help speed up future croc skull identifications, at least allowing certain species to be discounted.
If you have any good tips for crocodile identification please share below!
Last week the answer to the mystery object was a Gharial – a very weird crocodilian from India. I realised that I didn’t know much about identifying the Crocodyliformes, so I thought it might be fun to have a go at working out what this species might be:
As always, I would love to hear your thoughts below and let’s see if we can find some good diagnostic features!
This week I have a specimen for you that I found in the stores of the Grant Museum of Zoology:
I have a strong suspicion that I know what it’s from, but I’d really appreciate your thoughts!
Last week I gave you this pretty cool skull from the Grant Museum of Zoology to identify:
On Twitter the prevailing hypothesis was that this is the skull of an Alien Xenomorph, which was also proposed by Daniel Calleri, but most the comments here on Zygoma were a bit more down to Earth.
The identification started being narrowed down by Sisyphus47 and palfreyman1414 who recognised it as a reptile, which was narrowed down further by joe vans to a fossorial (or burrowing) lizard.
Allen Hazen, John D’Angelo and Daniel Calleri took it another step further and identified this as an amphisbaenian or worm lizard, but Rebecca Watling went even better and identified it as the skull of a Red Worm Lizard Amphisbaena alba Linnaeus, 1758. The morphology is very close and the size is right, so that’s the identification I’d also reached.
Amphisbaena alba by Diogo B. Provete
I’ve talked about Amphisbaenia before, but this one is a good bit bigger than most other species and the skull is oddly similar to that of a Weasel. I’m not really sure why, because the diet of these strange reptiles is very poorly known. It seems likely that they’ll eat invertebrates and small vertebrates, presumably in burrows, which does actually sound similar to a Weasel.
Weird, but pretty awesome!
This week I have a pretty interesting little skull from the Grant Museum of Zoology for you to try your hand at identifying:
Any ideas what this might be from?
As usual you can leave your answers below – I have a feeling that some of you will find this easy, so please try to be a bit cryptic with your suggestions. Have fun!
This week I have a genuine mystery skull for you to identify from the Grant Museum of Zoology:
I think I know what it is, but I’d be keen to see if you agree with me.Probably a bit on the easy side, so please keep your answers cryptic to avoid spoiling the fun for others!
Oh and apologies for the substandard photos – I used my phone with a tripod, which sort of worked, but it’s not ideal. Hope it’s good enough for you to make an identification!
Last week I gave you this ungulate skull to try your hand at identifying:
It isn’t made any easier by the fact that it’s a female, so it lacks the horns or antlers that make identification easier. As with many ungulates it looks a bit sheepy (as I’ve mention before), but it has some clear indicators that helped you rule out what it’s not.
Jake spotted that the size was about right for a Roe Deer, but the auditory bullae (the bulbs on the underside of the skull that house the ear bones) are too massive and the proportions of the braincase are quite different.
Joe vans also ruled out deer, since it lacks lacrimal pits (large openings in front of the eyes that hold scent glands in cervids). Joe also noticed that the mandible is extremely pinched in just behind the incisors.
The incisors themselves caught the attention of Allen Hazen, who noted the extreme size of the first incisor, which he correctly recognised as being a bit of a giveaway to some people, although only when considered in the context of a variety of other features.
While Daniel Calleri summarised these odd features and added the observation of the decent sized occiptial condyl (the place where the atlas vertebra attaches to the skull) and small paracondylar processes (the bony extensions either side of the occipital condyl and just behind the auditory bullae).
These sorts of observations are exactly what are needed to differentiate between species that are very similar in overall morphology. However, without either an excellent reference collection, or even better, a well researched key, it’s almost impossible.
Fortunately, there is a skull key for a subset of Antelope that occur in Tanzania, created by the Field Museum and the mystery object this week happens to be from a genus present in Tanzania. I’d recommend having a go at using the key, but if you’d rather just find out the answer I’ve provided a link to what it is here. Have fun with the key and enjoy your Easter!
Last week I talked about ungulates in collections being incorrectly identified as sheep. This week I have a specimen for you that is also not a sheep, although it does look a bit sheepish. Can you work out what it is?
You can leave your thoughts in the comments section below – I’m not sure they need to be cryptic, but it certainly adds to the fun!
Last Friday I gave you this skull to identify:
It was a bit of mean one, because although the family is fairly distinctive, it has poor species representation in online resources or indeed the literature.
The cranium is quite low and long, with some similarities to an otter, but the rostrum (or muzzle) is a bit too narrow and the teeth aren’t quite the right shape. Also the orbits are orientated more vertically, whereas otters have orbit that are at more of an angle so the eyes are closer to the top of the head.
The overall shape, dental configuration and median lacerate foramen all suggest it’s a member of the Herpestidae.
Narrowing down the species was a step too far however, after all, there are around 34 species spread across Africa, Madagascar and Asia and Europe and they are generally quite similar in cranial morphology, with only a few species having good descriptions of the skull.
To help challenge the lack of images of mongoose crania online, I’m pleased to say that this specimen does have an identification – it’s a Ruddy Mongoose Herpestes smithii Gray, 1837. While the name Ruddy Mongoose makes it sound like it’s annoyed me, it actually refers to the reddish-brown of its coat.
A Ruddy mongoose from Daroji wildlife sanctuary in Karnataka, India. By Kalyanvarma, 2009
This species is endemic to India and Sri Lanka, where it lives in dry, forested hills and feeds on pretty much anything it can get hold of, from snakes to bird eggs. As with other mongooses (or should that be mongeese?), they have a mutation that prevents snake neurotoxins from bonding at receptor sites, meaning that they are immune to some types of venom – pretty handy if you’re going to eat snakes!
This week I have another specimen from the Grant Museum of Zoology for you to try your hand at identifying:
I have a feeling that it may be easy to get this identification to Family level, but species may prove a little bit more tricky.
I’d love to hear what you think it might be, so leave your suggestions in the comments box below. Have fun!
Last Friday I gave you this odd looking V-shaped bone to identify:
It led to a lot of speculation on Facebook and Twitter, with ideas including a bird wishbone, hyoid or mandible. However, the comments on the blog tended to be a little more focussed in the area of the mandible of an ant-eating mammal.
The two little prongs at the anterior of this lower jaw are a bit of a give-away about which type of ant-eating mammal it is, as they are only seen on one family. When you look at the additional image I provided it becomes even easier to work out which:
As most of you correctly worked out, this is a specimen of Pangolin, of which there are four species in the genus Manis (thanks Allen Hazen for the correction – there are more like eight species in the family). I found this nice illustration of the skulls of the various species, to help narrow it down even further:
.jpg)
Anatomical and zoological researches: comprising an account of the zoological results of the two expeditions to western Yunnan in 1868 and 1875; and a monograph of the two cetacean genera, Platanista and Orcella. John Anderson, 1878.
So it appears from the morphology of the premaxilla, zygomatic region and nasals that this is a Sunda Pangolin, Manis javanica Desmarest, 1822.
Manis javanica by Piekfrosch, 2006
These unusual scaly insectivores are critically endangered due to poaching for their meat, skin and scales for the Chinese market, with their population suspected to have declined by 80% in the last 20 years, despite having a protected status. Sad to say that their ability to roll into an armoured ball does nothing to protect them from people.
This Friday I have another mystery object for you from the Grant Museum of Zoology:
This one is a bit of a tricky one, so I’m not sure the usual cryptic clues will be necessary – I’d love to hear your thoughts to see if you agree with my thoughts…
Have fun with this one!
Last week I gave you this mystery object from the Grant Museum of Zoology to have a go at identifying:
If you’ve been checking the mystery object recently you’ll notice that this specimen has a feature of the palate that I made reference to in the answer to mystery object #267 – the Tasmanian Devil. It’s incompletely ossified, which is a characteristic of marsupials.
The large curved canines and pointed premolars suggest some predatory activity, while the flattened molars suggest some grinding of vegetation, making this one of the marsupial omnivores, in the Order Peramelemorphia.
The large size of the skull and the long curved canines make this specimen rather distinctive – as first spotted by Richard Lawrence, this is indeed a Continue reading
