Friday mystery object #456 answer

Last week I gave you this rugged skull, from a rugged place, to have a go at identifying:

As everyone spotted, this is a whale of some sort (what else has a skull that weird-looking?), but the question is, which species?

The location led to a few suggestions of Arctic / sub-Arctic species like Narwhal or Beluga, but they have a much flatter top section of the skull. In fact, those huge vertical lobes of the maxillae seen here is pretty unusual and quite distinctive (even if it is a ittle weathered and broken):

This reminded me of a specimen in the collections of the Dead Zoo and which I had to check, just to be sure of my identification:

As spotted immediately by Chris and not too long afterwards by Adam Yates and Wouter van Gestel, this is the skull of a Northern Bottlenose Whale Hyperoodon ampullatus (Forster, 1770).

This sub-Arctic species has a distribution across much of the North Atlantic. They tend to stick to quite deep water, which makes sense in the case of the specimen I shared from Iceland, since the Reynisfjara beach is infamously dangerous because it shelves off very steeply into very deep water, making the waves that break along the beach behave in an unusual (and frankly terrifying) way.

Occasionally this species will come into shallower waters, in one (somewhat tragic) case a female Bottlenose Whale swam up the Thames (and is now in NHM, London). Our specimen came from an animal stranded on the Irish coast and there are theories that maritime sound pollution is connected to them being driven into shallower waters.

Well done to everyone who worked out which species this skull is from – hope you’re ready for another mystery next week!

Friday mystery object #369 answer

Last week I gave you this weird, but rather nice object to have a go at identifying:

mystery369

Most people seemed to recognise it as the tympanic region (that’s the bony ear-related region) of a whale. But of course, I’m demanding when it comes to getting an identification and there are plenty of species of whale to rule out.

The size immediately narrowed down the possibilities – this is pretty small for a whale. But what really gives it away for the small number of people intimate with the cranial anatomy of whales (which goes beyond even my bone-nerdery), is the spongy bone attached to the tympanic bulla (that’s the bulb-shaped bit of bone that houses the inner ear).

This feature is proposed as a possible pressure receptor that’s found in the Pygmy Sperm Whale Kogia breviceps Blainville, 1838. Amazingly, Conor Ryan identified this on Twitter – his handle of @whale_nerd explains everything you need to know.

Kogia breviceps by George Brown Goode, 1887

Kogia breviceps by George Brown Goode, 1887

These toothed whales only grow to around 3.5m, which is pretty small for a whale. They share some features with their much larger Sperm Whale cousins, particularly in relation to adaptations for echolocation.

I was fortunate enough to meet Conor Ryan at the weekend at the Irish Whale and Dolphin Group conference. There were plenty of whale enthusiasts around and it was fantastic to get a chance to learn more about this incredible group of animals from a lovely bunch of passionate people.

While I was there, I also picked up some useful tips on differentiating between species of dolphin, so I may have to share those with you soon…