Friday mystery object #346 answer

Last week I gave you this funky fossil from the National Museum of Ireland to have a go at identifying:

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Everyone in the comments immediately recognised that this is the fossil of something that flies, thanks to the slender bones. The general consensus from the outset was that it was Archaeopteryx, but I wonder how much of that is because this specimen is preserved in the same Middle Jurassic lithographic limestone from Solnhofen that preserves the first bird?

The Berlin Archaeopteryx

The Berlin Archaeopteryx

However, Allen Hazen noticed the long slender finger that marks the mystery object as something different, when he correctly suggested that it was a pterosaur, winning over palfreyman1414 and sallie reynolds. On Twitter, @Robertgagliano1 went one better and got the correct genus when he suggested Germanodactylus.

This is indeed a fossil of Germanodactylus cristatus (Wiman, 1925). These small Jurassic pterosaurs were about the size of a raven and it is thought that they may have fed on marine crustaceans and molluscs, based on their fairly robust teeth.

This particular specimen is currently on display in our Jurassic Skies exhibition (that I talked about a fortnight ago), as it helps represent the successful group of flying reptiles that were already in the air 150 million years ago, when feathered dinosaurs first took to the skies.

In an unexpected twist, research was published just a week after we opened the exhibition, describing the first evidence for feathers in pterosaurs. This was unexpected, although fur-like filaments had already been recognised in the group. This means it’s possible that feathers originated in a common ancestor of dinosaurs and pterosaurs – which may have even included the group that is today represented by the crocodiles.

This means it’s possible that the ancestors of crocodiles would have been feathered and modern crocodiles have lost this covering, possibly thanks to their specialisation for living in water. I find it quite interesting that a reticence to add feathers to representations of dinosaurs (in things like Jurassic Park) has been influenced in part by the scaly skin of modern crocodiles (the nearest living relatives to dinosaurs that are not birds), but now we find out that crocodiles may have had feathers and lost them, making prehistory a much more fuzzy place than we ever dreamed!

Friday mystery object #205 answer

Last Friday I gave you these tiny bones to identify:

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Several suggestions were put forward with soph coming close with the suggestion of a broken furcula and Lena and henstridgesj correctly suggesting the clavicles (or collarbones) of a Cat Felis catus Linnaeus, 1758.

Cat clavicles, like the clavicles of a variety of other animals, are much reduced and are no longer connected to the scapulae (shoulder blades). This allows the scapulae to move much more freely during running, which can increase stride length and in the case of Cats it allows the animal to fit through holes big enough to get their heads through (assuming the Cat isn’t a bit too portly).

These sorts of vestigial structures are interesting from an evolutionary perspective, since they serve little or no direct function, but they still develop as a result of inheritance from ancestral forms that did use them.

In the case of Cats that form would have been around quite some time ago (probably 61.5 – 71.2 million years ago) since the closest related group to the Carnivora with a well-developed clavicle (that I can think of) would be the Chiroptera (bats), where it plays an important role in flight.

Since that divergence of the Chiroptera and the lineage giving rise to the Pangolins, Carnivora and Ungulata the clavicle has been pretty much completely lost, so it’s interesting that even a vestigial form occurs in Cats.

It’s funny to think how such small bones can raise questions that lead us through millions of years of evolution in search of answers, but that’s the nature of studying nature!

Friday mystery object #130 answer

On Friday I gave you this specimen to identify:

I thought that some of you might find it a bit tricky, since this is a shell from a group of animals that aren’t that familiar to most people.

Barbara Powell was the first to spot what this shell came from and her identification was supported by Dave Godfrey, Julie Doyle and henstridgesj. It’s a   Continue reading

Friday mystery object #112 answer

Below is Rachel’s follow-up guest post answer to last Friday’s challenging mystery object. Many thanks Rachel – it was a good one!

Well, I seem to have led you all a merry dance this week! Admittedly, it was sneaky to not include a scale bar or provide you with another view of the skull, but if I’d put the top view in I think it would have been game over in about five minutes…

As cromercrox so rightly pointed out, it is a bird skull. Many of the guesses tended towards water birds, with suggestions including goose, gull, and rail.

Manabu Sakamoto was the first to suggest a ratite, and later tentatively guessed ostrich, while Matt King went for a rhea.

Paolo and I actually thought it might be a rhea to start with, but after comparing it to an identified rhea skull in the collections and the ratite images on Skullsite, we decided that it is in fact an  Continue reading

Friday mystery object #111 answer

On Friday I gave you this object (from the NHM) to identify:

It was a bit of a tricky one for those of you who haven’t seen the First Time Out exhibition (jackashby and David Godfrey obviously did see it). This fossil skull looks like it belonged to some kind of pig rather than a primate – yes, that’s right, I said primate.

The main feature visible here that indicates that this skull may belong to a primate is the enclosed orbit, which isn’t a particularly strong characteristic since various ungulates also have an enclosed orbit – as I said, it’s a tricky one.

The type of primate is the Koala Lemur Megaladapis edwardsi Forsyth Major, 1894 from Madagascar. It was an arboreal, slow moving, gorilla-sized folivore – with superficial similarities to Koalas (hence the name). It is hypothesised that the extended bony nasal region may have supported a prehensile top lip, that would have been beneficial when foraging for leaves in the trees.

I won’t go into much detail here, because other curators have provided their interpretation for this object as part of the First Time Out project, so I will leave you with a link to that information. However, I would be interested in taking a closer look at the dentition and complete skeleton of one of these animals – I’d like to get a better grip on this apparent convergence on a suid cranial morphology and more gorilla-like body. I wonder what it might have looked like?

Gamorrean Guards by Dextar FX