Friday mystery object #292

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?:

dsc06030No 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!

Friday mystery object #291 answer

Last week I gave you this skull from the Grant Museum of Zoology to identify:

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I thought this would be a fairly easy one and so I wasn’t surprised when Chris was straight in with a correct identification, in a suitably cryptic manner of course.

The huge open sinuses inside the orbit and openings around the auditory bullae (as spotted by palfreyman1414) immediately suggest that this is an animal that dives deep underwater, as the large openings help prevent pressure from building up inside the skull. The shape of the teeth are another giveaway that this is a fish-catching mammal in the Order Carnivora. It is of course a seal.

But what kind of seal? There are 33 species of pinniped, so there are a few options, although the large and distinctive species like Walruses can be ruled out for obvious reasons. In this size range and with multicusped teeth like these we’re looking at one of the true seals (the Phocidae) at the medium to small end of the size range.

When you start looking at the skulls of seals in this range, you need to look  closely. It lacks the flat top of the head and steeply sloping profiles following the nares of a Grey Seal, plus the interorbital distance (the distance between the eyes) is much smaller.

It lacks the inflated nasal region of the cold water Bearded Seal, Ribbon Seal, Ringed Seal and Harp Seal, which need well developed nasal turbinates to help warm the air they breathe in. It also lacks the deflection of the zygomatic below the orbit that is seen in the smaller species like the Caspian and Baikal Seals.

Overall the morphology is most similar to either the Spotted Seal or Harbour Seal, but picking between the two is tricky, especially since the Harbour Seal has around five subspecies that vary somewhat in size and shape of things like the auditory bullae. There is a list of characters that can be used to distinguish between the skulls of the two species by John J. Burns in the Encyclopedia of Marine Mammals. Using that as a guide I think this is a Harbour Seal Phoca vitulina Linnaeus, 1758.

Thanks to everyone who had a go at identifying this – I hope you had fun with it!

Friday mystery object #289

This week I’ve decided to go for another mini mystery object from the Grant Museum Micrarium. Any idea what this is and what it’s from?

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As always, your thoughts, questions and suggestions can go in the comments box below.

Also, if you have any images of tiny things you can share them on Twitter with the hashtag  to win a signed copy the excellent new book by Ed Yong – it’s well worth a read!

Have fun!

Friday mystery object #288 answer

Last week I gave you this mystery object from the Grant Museum of Zoology to try your hand at identifying:

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Not the best photos, but they do show some of the key features I used to work out what it is.

There were a lot of comments with a variety of different groups of animal being mentioned, although everyone recognised this as a mammal immediately. The large broad tail was recognised by Allen Hazen as an adaptation to swimming, but its unusual proportions threw some people into thinking this was something quite basal, like a marsupial or member of the Pilosa. The presence of a clavicle supported that to some extent as many of the more recent mammal orders, like the Carnivora, have a reduced or absent clavicle.

The hind feet were also recognised as an adaptation to swimming by palfreyman1414, but he was sceptical that this specimen represented just one species, suggesting it might be a chimera. However, I wouldn’t do that to you (unless it was an April Fool prank) so the real animal remained to be identified.

Hiroto Nakatsubo raised the possibility of it being a rodent, but commented that it was on the big side. This could have pointed at Beaver, as many people suggested, except the specimen lacks the distinctive tail morphology. All of this followed my own though path for working out what it is – a medium large aquatic rodent that isn’t a Beaver.

That narrowed it down to Capybara, Muskrat, Coypu or monster Water Vole. Of these, only one has the size difference between fore and hind limbs, plus the distinctively weird acromion process on the shoulder – the Coypu Myocastor coypus Kerr, 1792. So Isaac Krone was the first to get the correct identification, which he hinted at with reference to the Coypu’s alternative common name Nutria and the genus name which means “mouse-beaver” in Greek. Well done to Isaac!

Coypu showing off its weird discrepancy in limb lengths. Image by José Reynaldo da Fonseca, 2006

Coypu showing off its weird discrepancy in limb lengths. Image by José Reynaldo da Fonseca, 2006

 

 

Friday mystery object #288

This week I have a mystery skeleton that emerged from the collections of the Grant Museum of Zoology recently and required identification:

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Apologies for the slightly rubbish photographs, but I’ve taken pics of the bits I found most useful in making my identification.

Any thoughts on what species this specimen represents? You can put your questions, thoughts and suggestions in the comments section below. Have fun with it!

Friday mystery object #287 answer

Last week I gave you this specimen from the Grant Museum of Zoology Micrarium to try your hand at identifying:

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I enjoyed the variety of entertaining answers, ranging from a preschool drawing of a grandma with a beehive hairdo to a larval Alien, but I was also impressed by the range of cryptic clues about the identity of the specimen.

A favourite was a reference to “dealing with a pea covering” or variations on that theme, which gives us “Cope” and “pod”, which is what this is – a Copepod (which means “oar-foot” in Greek). For those of you unfamiliar with copepods are small crustaceans, many of which live as zooplankton and that as a group may make up the majority of the Earth’s animal biomass. They’re tiny, but there are countless billions of them.

This one isn’t as tiny as many of its relatives, because it has a rather different lifestyle to planktonic forms. This is a sea louse and it’s a parasite of fish. They feed on the mucus, skin and blood of fish and if they reach high levels of infestation they can be a real problem, potentially killing fish. This particular specimen has two trailing egg cases, which I think threw some of you. It was removed from a Brill and as Daniel Calleri recognised from a visit to the Grant Micrarium, it’s Lepeophtheirus hippoglossi (Krøyer, 1837).

If you’ve been to the Grant Museum and have photos from the Micrarium, or if you have any photos of tiny animals, you might fancy entering a Twitter and Instagram competition by sharing them with the hashtag #MicroMultitudes, Have fun with your photos!