Friday mystery object #316

Back to bones this week, with a mystery skull for you to identify. Any idea what species this skull belonged to?

mystery316

I don’t think it will prove too much of a challenge for the bone geeks among you, so please try to be a bit cryptic with your answers to keep it fresh and fun for those who are not so familiar – and that’s a cryptic clue about what it’s not right there ūüôā

Have fun!

Friday mystery object #315

It’s been another week of working with the Dead Zoo insect collection for me, so I thought I’d give you one of them to have a go at identifying:

mystery315

A big bug  at around 135mm wingtip to wingtip

I don’t think it’ll be particularly difficult for some of you, so please try to offer cryptic suggestions if you know what is, to keep it challenging for others who aren’t as familiar with these impressive invertebrates.

Have fun!

Friday mystery object #314 answer(ish)

Last week I gave you this guest mystery object, courtesy of Joseph van Sambeek:

Mystery object. Image by Joseph van Sambeek, January 2000

The bony struts reinforcing thin plates of bone show it’s from something that lives in water all the time and which lacks lungs – you can tell this because this structure is what you get when you’re dealing with forces moving in a variety of directions, rather than mainly dealing with the constant force of gravity or compensating for buoyancy that is unavoidable when you live in water, but have lungs.

This means that many of you recognised it as being the neurocranium (that’s the bit of the skull that surrounds the brain) from a fish – more specifically from Sarah Gibson:

The first image is the skull roof, showing the elongated frontals and parietals (front of snout is left in first three images). Second image is a left lateral view, showing the internal parasphenoid that would pass between the two eye sockets. Third image is a ventral view, showing the bottom of the parasphenoid. And obviously last image is posterior view, showing the foramen magnum where the spinal cord would pass through, over the occipital condyle. It just may not look like a skull to some because it’s missing the eye sclera bones, jaws, cheek bones, pretty much anything that is not the skull roof or braincase.

However, as we all know, there are a LOT of different sorts of fish Рaround 33,600 described species and counting. This can make fish a nightmare to identify. However, there are some great resources out there, like Osteobase which has a very useful identification guide for various elements of a range of fish.

Alas, Osteobase didn’t have anything that fits this mystery specimen, so narrowing down to a species is rather difficult. I had the advantage of knowing that the specimen was collected in Baja California, although that was of little help in trying to get in an approximate area of the fishy family tree based on morphology, and there are still a ridiculous number of fish species is the area.

Sarah Gibson suggested that it may be a Barracuda, and it certainly fits in many aspects, but the shape of the frontals and parietals and details of the point of connection between the parasphenoid (that’s the bottom bar bit you see in the side view) don’t quite fit.

I had almost given up hope, when it occurred to me¬†to concentrate on understanding the unusually large occipital condyle that Allen Hazen noticed, which suggested that it might be a taxon with an extremely extended rostrum (like the paddlefish or swordfish that Jennifer Macaire suggested) but with a weedier body and defined neck region since there would be no need for such a large articulation in a fusiform fish (they’re the muscular type that taper at both ends and have no neck, so don’t move their heads).

With this bizarre sounding fish in mind I was able to fairly rapidly narrow down the possibilities to one of the three species of cornetfish that live in the Pacific. I was delighted to find some great images of the skull of a Red Cornetfish, which matches the morphology very well.

Red Cornetfish Fistularia petimba from the Gulf of Mexico. Image by SEFSC Pascagoula Laboratory; Collection of Brandi Noble, NOAA/NMFS/SEFSC

Red Cornetfish Fistularia petimba from the Gulf of Mexico. Image by SEFSC Pascagoula Laboratory; Collection of Brandi Noble, NOAA/NMFS/SEFSC

However, the Red Cornetfish doesn’t really occur in the eastern Pacific, so it’s very unlikely to be that species. The Reef Cornetfish does occur in the eastern Pacific, but has only been reported in Californian coastal waters since November 2015¬†and this mystery specimen was collected back in January 2000 (which doesn’t make it impossible to be a Reef Cornetfish, just very unlikely). Which leaves us with the most likely identification (although by no means confirmed) of Deepwater Cornetfish Fistularia corneta Gilbert & Starks, 1904.

These long, thin fish can reach up to 2m, but they have tiny mouths that limit them to eating crustaceans, marine worms and smaller fish that they pick up from near the surface of reefs and the sea bed – presumably being harder to spot as a predator thanks to their very small frontal projected area.

I’ve asked Joe to check his specimen against the images of the cornetfish, since there’s nothing better than having a specimen in your hand when attempting an identification.

I hope you enjoyed the challenge!

Friday mystery object #312 answer

Last week I gave you this specimen to identify, which came in as an enquiry after being found in someone’s toilet:

There were a variety of great responses, with some fantastic cryptic clues, including an anagram by Claire Miles (great stuff!). Most opted for this being Stegobium paniceum, which is also known by the aliases Drugstore Beetle, Biscuit Beetle or Bread Beetle.

Stegobium paniceum by Sarefo, 2007

Stegobium paniceum by Sarefo, 2007

However, the mystery critter has a subtly different pronotum (that’s the plate over the thorax that extends over the head).

Another suggestion was woodworm or one of the false powderpost beetles, which covers a range of wood-boring beetles, with Liberty Hightower correctly giving the more taxonomically constrained suggestion, of something from the Tribe Anobiini (which includes Stegobium). However, my colleague Olivier sent me an email with a very definitive identification, informed by a past experience with this particular pest Рthe Furniture Beetle Anobium punctatum De Geer, 1774.

These beetles have a distinctive pronotum that supposedly looks like a monk’s cowl, with a more distinctive hump and slightly pinched looking back section than the more smoothly curving pronotum of the Stegobium. They fall into the broad category of woodworm because their larvae feed on wood, making tunnels hidden from view and only becoming visible when they emerge from small holes in the wood as adults, leaving a little pile of wood dust as they go.

The presence of these beetles in a toilet isn’t related to the water in the bowl or even wood of the seat – it turns out that there was a window above the toilet and the adult beetles, in an attempt to leave the building after emerging, were attracted to the light from the window and flew into the glass only to bounce off and land in the toilet.

This attraction towards light in the dispersing adult stage of the beetle is a handy behaviour if you want to keep track of these pests. If you’re concerned you may have active woodworm it’s worth checking your windowsills in the summer to see if you have any of these adult beetles lying around. Of course, there are other species that would also be worth checking for, since there are plenty of beetles whose larvae would be considered woodworm. Keep your eyes peeled!

Friday mystery object #311 answer

For the last couple of weeks I’ve been offering up what has been affectionately nicknamed ‘cave snot’ for identification:

mystery311a

The initial goop was a bit too difficult to identify from a photo, so I dug in and pulled out the critter responsible:

mystery311c

This proved much more identifiable, with Chris immediately recognising that it’s the larva of a Caddisfly (not really a fly, but a more moth-like insect in the Order Trichoptera – which means ‘hairy wings’ as palfreyman1414 mentioned). Natalia Maas went one better by alluding to the family – the Philopotamidae or Finger-net Caddis, explaining¬†the goop, which is actually made up of little silk nets shaped like fingers (hence the common name for the family). These nets are used to collect organic detritus and diatoms from flowing water, which the larvae then feed on.

I provided a couple of extra images to help narrow down the identification, since there are only five species in three genera of Finger-net Caddis in Ireland (and England for that matter), which are able to be differentiated from the anterior margin of their frontoclypeus (see the diagram below if you’re not sure what that is).

caddis-frontoclypeus

There’s an excellent website looking at Trichoptera in Ireland, descriptively called TrichopteraIreland, where you can find the details of how to tell the larvae of different genera apart, but the short version is to look at the frontoclypeus and if it has a deep U-shaped notch in it you have a¬†Chimarra marginata, if it has a shallow V-shaped notch in it then you have¬†Philopotamus montanus and if it’s a smooth curve then you have a species in the genus¬†Wormaldia (which could be W. subnigra, W. mediana or W. occipitalis).

Unfortunately you can’t readily tell Wormaldia species apart when they’re larvae, so unless I’m missing a well-hidden notch in the frontoclypeus, we can’t identify this to anything better than genus level – but that’s still a substantial improvement on simply calling it cave snot.

I’ll be taking the specimen to the previous Entomology curator of the Museum, since his area of specialist interest is Caddis, so I’m sure he’ll be able to confirm the identification and I expect there may be some interest in where it came from.

More mysteries next week!

Friday mystery object #311 part 2

Last week I gave you this delightful jar of ‘cave snot’ to have a go at identifying:

mystery311a

Perhaps unsurprisingly, nobody came close to identifying what this is. I didn’t have a clue until I dived in and dissected out a small sample:

mystery311b

Notice the little critter on the left of the image? This immediately made it much more obvious what this stuff was – not something living in its own right but something produced by an animal.

Removing the goop reveals what we’re really dealing with:

mystery311c

mystery311e

mystery311d

I think I’ve given you all the images needed to work out what this is, so rather than just tell you, I’m making this part 2 of the mystery object, with quite a lot more to go on than the first post. So, as usual, you can put your questions, thoughts and suggestions in the comments section below. Have fun!

Friday mystery object #311

This week I have a real mystery object for you, which came in as an enquiry from the bottom of a mine in Ireland that was flooded to the roof with freshwater. It’s earned itself the delightful name of the ‘Clonkeen snot’ thanks to its appearance and texture:

mystery311

If you click on the image, it will open a large version so you can have a really good look at the fascinating gunk that was fished from the subterranean dankness.

Any ideas what this might be?

As always you can leave your questions, thoughts and suggestions in the comments section below. Have fun!

Friday mystery object #310 answer

Last week I thought it was time for some more bones, so I gave you this specimen from the Dead Zoo to have a go at identifying:

mystery310

There was no scale, the photo is far from ideal and the specimen isn’t in the best condition, but the animal is pretty distinctive, so I thought it wouldn’t prove too much of a challenge – and it turns out that I was right.

Palfreyman1414 was the first to identify it to genus level, correctly recognising that it was one of the two Notoryctes species of Marsupial Mole from Australia.

The weird limbs are a pretty good indicator this being a digger, with large muscle attachments and robust forelimbs, but it has couple of large claws rather than the ridiculous giant hands of the Old World Moles and it has a shorter skull.

Double prep mole from the Horniman Museum

Double prep of an Old World Mole Talpa europaea from the Horniman Museum & Gardens

The skull is more similar to that of the golden moles of southern Africa, although their rostrum (nosey bits) tends to be more concave while the marsupial moles have a more convex rostrum (and in some cases, weirdly flaring zygomatic arches).

mystery268

Lateral view of the skull of a Giant Golden Mole Chrysospalax trevelyani from the Grant Museum of Zoology

Now distinguishing between the two species of Marsupial Mole is a bit more tricky, not least because they are quite poorly known animals and there aren’t many specimens available for comparison – this is particularly true of the Northern species, which was first described as recently as 1920.

This is actually quite useful to know, since the mystery specimen came into the collection in 1897 – from Southern Australia – so it’s safe to say it’s the Southern Marsupial Mole Notoryctes typhlops (Stirling, 1889), but that’s not very helpful from a morphological perspective.

So far I’ve not found any useful skeletal features that help differentiate the two species, but apparently their fur colour is a little different, with the Northern species having pinkish or cinnamon fur and the Southern species having yellowish-white to a deep gold. To see what they look like with their fur, here’s the taxidermy partner to the mystery skeleton:

Southern_marsupial_mole

Taxidermy Southern Marsupial Mole Notoryctes typhlops in the National Museum of Ireland – Natural History

As with most moles these subterranean critters have adapted to spending much of their time underground by losing their eyes, investing in some serious digging equipment and tuning in to smells and low frequency sounds.

I hope you enjoyed this little tour around the main moles of the world! More mysteries next week.

Friday mystery object #308 answer

Last week I gave you this beautiful insect to try your hand at identifying:

mystery308

From the start it was pretty clear it’s a wasp (just look at that characteristic waistline) and palreyman1414 pointed out the key things to look for in making sure it isn’t a fly pretending to be a wasp:

I believe that there are some flies that are camouflaged to look like wasps, but a close look suggests that this thingy has a full complement of four wings, instead of the two plus two halteres (?) that characterises the flies

Now there are a LOT of wasps out there – somewhere in the region of 150,000 species (more than all of the vertebrates put together) so that doesn’t narrow it down much. However, that waist isn’t just pinched-in like your average wasp, it’s petiolate (that’s science-talk for “stalked”), which means it’s one of the Sphecidae.

The large size also helps – most wasps are tiny, so big ones like this are relatively scarce, especially bright metallic green-blue jobs.¬†This distinctive appearance brings to mind for me the Steel-blue Cricket Hunter (see below), but it’s from the wrong part of the world (and it’s more green than blue).

640px-chlorion_aerarium_2_biml_usgs

Chlorion aerarium from Maryland, USA, July 2012. Image by USGS Bee Inventory and Monitoring Laboratory

However, we know there are a lot of wasps, so it’s worth looking at close relatives in the Sphecidae, to see if there is anything from the right part of the world (that’s made reasonably easy by using an appropriate reference with a checklist).

It turns out that we don’t need to look too far, as the mystery specimen looks like it’s in the same genus of Cricket Hunters – Chlorion (as suggested by Ilyas) and checking out the species occurring in India has me leaning towards Chlorion lobatum (Fabricius, 1775), which is what abcdefg200¬†hinted at.

These active hunters don’t eat Crickets themselves, they actually get their energy from nectar, so they’re helpful pollinators. The Crickets face a more grisly fate than just being killed and eaten – they are paralysed, then buried alive with a wasp egg laid on them, which subsequently hatches and the larvae eat the still-living Cricket. Nightmare fodder.

There are a few subspecies of this particular species of wasp, but I’m not even going to try to work out which this might be, since even carrying out a proper identification to species would require time with a microscope and a lot more experience than I have with this diverse, fascinating and above all nightmarish group of insects.

Friday mystery object #308

As I’ve mentioned before, for the last few months I’ve been feverishly moving objects for a gallery lighting project. 

That’s pretty much done now (and looking great) so now I’m feverishly moving the Dead Zoo’s collection of over a million insects out to a new home in the National Museum of Ireland’s Collections Resource Centre.

So this week I have an insect for you to identity, which should provide a bit of a colourful change from the usual vertebrate bones:

For some of you this may be way too easy, for others, way too hard. It help to know that this was collected in India and it’s around 25-30mm long.

I hope you have fun identifying it!

Friday mystery object #307 answer

Last week I gave you this specimen from the Irish Room of the Dead Zoo to try your hand at identifying:

mystery307

Now it’s not a particularly difficult species to identify for a keen birder, so I asked for cryptic clues to the identity, and I was not disappointed. Some suggestions were so cryptic I still haven’t managed to work them out!

First in was Jennifer Mccaire who quoted a brief line of poetry:

‚Äú‚ĶThou hast no sorrow in thy song, No winter in thy year.‚ÄĚ

This is a section of a poem published in 1770 by John Logan – the title being “Ode to the Cuckoo“. Now, it seems likely that Scottish born Logan wrote this about the Common Cuckoo¬†Cuculus canorus Linnaeus, 1758 that breeds in Europe and which looks like this:

Common Cuckoo. Image by Chris Romeiks, 2011

Common Cuckoo. Image by Chris Romeiks, 2011

Clearly it’s a different bird (one which mimics the appearance of a female Sparrowhawk) and it’s not quite the same as the mystery object – although there are similarities. However, we must keep in mind that Jennifer is of the North American persuasion, so her thoughts on Cuckoos will probably veer towards the Black-billed Cuckoo or Yellow-billed Cuckoo (or maybe the Mangrove Cuckoo, but that’s not as widespread as the other two).

If you don’t know the difference between these two North American Cuckoos, here’s a handy illustration to help differentiate:

Black-billed Cuckoo (left), Yellow-billed Cuckoo (right). Watercolour by Louis Agassiz Fuertes between 1910 and 1914.

Black-billed Cuckoo (left), Yellow-billed Cuckoo (right). Watercolour by Louis Agassiz Fuertes between 1910 and 1914.

Continue reading

Friday mystery object #307

The last few months have been particularly busy for me as I’ve been working on a lighting project in the Irish Room of the Dead Zoo in Dublin, so I’ve not had much opportunity to dig out mystery objects and get good images for you to identify.

However, I have moved pretty much every specimen in the gallery and if you want to see how much stuff that entails there’s a 3D interactive map of the space available here¬†(if you want to have a virtual tour of the whole museum check this out). All this moving means I’ve seen a lot of specimens, so here’s one of them for you to have a go at identifying:

mystery307

For a some of you this will be way too easy, so let’s have your best cryptic clues, hints and riddles as to what this is.

Have fun!

Friday mystery object #306 answer

Last week I gave you this interesting skull to identify:

Specimen LDUCZ-Z1058 from the Grant Museum of Zoology

Specimen LDUCZ-Z1058 from the Grant Museum of Zoology

I didn’t mention that top of the cranium had been removed, probably as part of a postmortem, which is quite common for zoo specimens. Of course, this made the identification a bit more tricky.

That absent skullcap led to several suggestions of Tasmanian Devil, since they do have a very similar looking facial region to this specimen, with a short and blunt muzzle, robust zygomatic arch and even the same toothcount in the upper jaw. However, the Devils have an angular process of the mandible that projects medially (towards the midline) rather than backwards in a hook, so you wouldn’t see it in a side view.

mystery166

The correct answer was first tenuously suggested by palfreyman1414 in a pleasingly cryptic manner:

I’d have sworn this was a commie go-between for Cressida and Troilus

Which hints at “Red” and “Pandarus” giving us the Red Panda Ailurus fulgens F. Cuvier, 1825.

Red Panda image by Mathias Appel, 2016

Red Panda image by Mathias Appel, 2016

These charismatic critters are another example of an arboreal carnivore that is adapted to feed on a highly vegetarian diet, but unlike the previous mystery object (a Kinkajou) these cuddlesome floofballs eat mainly bamboo rather than fruit – rather like their very distant relative the Giant Panda (despite the similarity in diet and common name, the Red Panda is actually more closely related to the Kinkajou than it is the Giant Panda).

Red Pandas are a bit less highly specialised for feeding on bamboo than the Giant Pandas, probably because they have a more varied diet that also includes fruit, eggs, birds and small mammals. The poor nutritional quality of bamboo does mean that they spend a lot of time sleeping and they tend to move fairly slowly in order to conserve energy, although they can be very playful, especially in captivity where they can access higher quality foods.

Sadly, this playfulness and supreme floofyness is a bit of a problem for the wild Red Panda population. There is demand for wild caught Red Pandas in the pet trade and they are hunted for their thick fur right across their range through the foothills of the Himalayas, despite being protected by legislation in every country.

Friday mystery object #305

This Friday I’m giving you a game of heads or¬†tails from the Collections Resource Centre of the Dead Zoo:

mystery305amystery305bmystery305cmystery305d

I don’t normally add a photo of the tail, but in this case it should make the identification a doddle – literally a 50:50 shot at getting the right species. If you know what I’m talking about, then please be cryptic in your suggestions – don’t spoil it for everyone else!

If you don’t know why¬†this tail is so significant then you should know that the skull is 10cm long and all will be revealed next Friday!

Good luck!

 

Friday mystery object #304 answer

Last week I gave you this skull to have a go at identifying:

mystery304

The skull of specimen LDUCZ-Z144 from the Grant Museum of Zoology

I thought that some of you would find it a bit easy, but¬†the most diagnostic features aren’t visible in the image and it’s a nice¬†specimen, so I went with it.

There is a bit of similarity with the skull of a ruminant, as noted by palfreyman14141, while Gerard pointed out¬†that it’s from Africa and James M. Bryan was the first to drop a solid clue pointing to the correct species. As jennifermccaire¬†says, it’s the very first on the list (assuming the list is alphabetical) – an Aardvark¬†Orycteropus afer (Pallas, 1766).

An Aardvark at Detroit Zoo by MontageMan, 2008

An Aardvark (or as I prefer to call it, a Tippy-toes McSnuffleface) at Detroit Zoo. Image by MontageMan, 2008

Picking up on palfreyman1414’s observation about it looking like a ruminant, Allen Hazen asked an interesting question about the teeth, because the diet of these bizarre looking animals almost entirely consists of ants and termites, and most other mammals with a similar diet (like Pangolins and Tamanduas) have no teeth at all.

Making the presence of teeth even more weird is the fact that Aardvark stomachs have a muscular pyloric region that grinds up food in a similar way to a bird’s gizzard, so they really don’t need teeth for the major component of their diet. To top it off, the teeth of Aardvarks are utterly unlike any other mammal teeth – they’re made of¬†tubules of dentine (giving the Order the name ‘Tubulidentata’), with no enamel, no pulp-cavity and no root – so they keep on growing:

The weird teeth of the Aardvark, made up of tiny dentine tubules.

The weird teeth of the Aardvark, made up of tiny dentine tubules.

All of this suggests that their dentition is distinctly non-standard, so it probably isn’t just a vestigial feature inherited¬†from a toothed ancestor – which¬†reinforces the importance of the question ‘why do they have teeth?’

Bear with me.

A 60-80kg mammal living in hot and water-scarce regions of Africa, will struggle to get enough moisture from ants and termites to survive, even if they are nocturnal and sleeping in burrows during the hottest part of the day. So how do Aardvarks do it?

Cucumbers, that’s how.

There is actually a species of cucumber that has a symbiotic relationship with Aardvarks, and¬†it’s unimaginatively, but descriptively, called the Aardvark Cucumber Cucumis humifructus¬†Stent, 1927.

Aardvark cucumber. Image by B. Strohbach

Aardvark cucumber (not a golf ball). Image by B. Strohbach

These weird fruits develop deep underground and have a tough skin that keeps them viable for months. Outside they’re like a leather golfball, but inside they’re watery like the cucumbers you’d put in a Hendrick’s gin and tonic – and that’s where the Aardvarks get their moisture (the Cucumber, not the G&T).

Nothing but the Aardvark¬†has a nose sensitive enough to detect the plant, or claws powerful enough to¬†dig into the hard-baked earth to access the fruits (or possibly only an animal that mostly eats ants¬†is desperate enough for some culinary excitement¬†to go to all that effort for something that the rest of nature views as a lacklustre garnish). The¬†Cucumber’s seeds need to pass through an¬†Aardvark to become viable and those seeds get distributed underground with a healthy dollop of fertiliser in what is otherwise a harsh environment.

The leathery skin of the Cucumber is almost certainly the reason why Aardvarks are alone in having teeth amongst the termite and ant-eating mammals. It also explains why those teeth grow constantly – and why they get so worn down.

I think that’s pretty awesome.

Now you may be wondering if I’m making all this up, but honestly, the world really is that weird (and wonderful) when you look at it closely enough!

Friday mystery object #303 answer

Last week I gave you this mysterious bit of bone from the Thames to have a go at identifying:

mystery303b

A few ideas were put forward, but DrewM was spot on with the suggestion:

I think it‚Äôs the synsacrum of a bird, without the ilia fused ‚Äď the foramina are for spinal nerves.

A synsacrum is a fused section of vertebrae including the sacrum (which is where the pelvis attaches to the spine). General opinion quickly agreed with that suggestion, but the taxonomic group that the synsacrum belongs to remained unguessed.

That is perhaps unsurprising, since it’s hard to find good comparative images of bird synsacra, especially with the hips and lateral (or side) bits knocked off and worn down.

chicken synsacrum

A Chicken synsacrum showing the section preserved in the mystery object

I had a go at looking through some of the comparative bird osteology collections at the Dead Zoo to get a feel for birds with a similar synsacral morphology.

The usual suspect for a bird bone found in the Thames (for me at least) is Chicken, since they’re so closely associated with humans and a lot of the bones washed up on the banks of the Thames are from butchery and food waste.¬†The size was about right, but¬†the vertebral centra (the middle bits) of the Chicken synsacrum become more narrow in the hip-line than in the mystery specimen.

Next I looked at ducks, whose centra taper more in the direction of the tail, then grebes whose whole synsacrum is more narrow overall:

grebe synsacrum

Synsacrum of a Great Crested Grebe

Eventually I made it to the gulls who seem to be a much better fit in terms of shape and the Herring Gull Larus argentatus Pontoppidan, 1763 was a good fit for size:

herring gull synsacrum

Herring Gull synsacrum

Now this doesn’t mean to say that the mystery object is certainly from a Herring Gull. I would want to have the object¬†in my hand and comparative material available from several specimens to check the identification before being sure, but on the basis of the images that¬†Keith Dunmall¬†kindly provided, I think we’re in the right ball park.

More mysteries next week!

Friday mystery object #302 answer

Last week I gave you this egg to try your hand at identifying:

mystery302

Eggs can be tricky, since they are largely similar in shape and, since egg collecting was banned many years ago, there are few modern resources for identification.

However,¬†you can pick up clues by¬†thinking about colour and pattern and working out what advantage it may have. So you might expect a brightly coloured egg to be laid in a well disguised and deep nest, where it’s unlikely to be spotted except by the parent, whereas a yellowy speckled egg is more likely to be camouflaged if laid in a fairly open, sandy environment.

So this egg was probably laid somewhere near the sea, which means it’s probably from a charadriiform bird (those are the shorebirds).

Now there are a lot of shorebirds, but this egg is pretty big and it lacks the strongly conical shape you’d expect from a cliff-nester like a Guillemot (the shape means it rolls in tight circle, making it less likely to be blown or knocked off a cliff). That actually narrows it down to a handful of birds that makes comparison easier. Curlew eggs, for example, are a similar size, but they tend to be more grey and have larger blotches, plus they’re a bit less elongated.

This particular egg has the shape and colour of a gull egg and large size means it’s almost certainly the egg of a Greater Black-backed Gull Larus marinus Linnaeus, 1758.

I would say more, but at the moment I’m at the natural history highlight of the year – the NatSCA conference. Here’s the Twitter feed in case you’re interested in the discussion: