Last Friday I gave you this big chunk of bone to identify:

I was hoping that it might be a little bit of a challenge because it doesn’t seem to have any really diagnostic characters, but your shape-matching skills were good and several of you managed to get a close identification.

Heather was straight in with the suggestion of it being the back part of the frontal bone (the bit that makes up the front and top of the skull) of an Aurochs – the very large, extinct ancestor of modern Cows. Wouter van Gestel also suggested one of the large bovids – the Asian Water Buffalo, and Ben Gruwier agreed with both Heather and Wouter in saying that it was from a large bovid.

This was as far as I had managed to get with the identification myself, however the specimen had a number (39.16), which I was able to check against the natural history registers. The first part of the number told me to check in the register for the year 1939 and it was the 16th entry for that year, so it was easy to find (unlike with some numbering systems with museum specimens).

It turns out that this specimen is in fact the frontal bone of a Gaur or Indian Bison Bos gaurus Smith,1827, and it turns out that the Gaur has a distinctive ridge between the horns, which is what this specimen is showing, so I should have been able to work it out from the morphology (I will be able to in future).

Bull Gaur can weigh up to 1.5 tonnes and stand 2.2m (7’2″) to the shoulder – they’re enormous. Their only natural predators are the Tigers and large Crocodiles they share their Southeast Asian forest habitat with, but even then Gaur have been known to kill Tigers by trampling and goring them.

Perhaps unsurprisingly these animals are far more risk from humans and have been hunted for meat and trophies until they have become threatened. They are protected by CITES (the Convention on International Trade in Endangered Species), but illegal trade continues and their forest habitats are constantly being lost due to human encroachment.

It’s disheartening that so many of my mystery objects end with a comment about human activities driving a species towards extinction, but unfortunately it’s a massive problem in the world we live in. I wonder if there will be any wild Gaur left in 2039, just 100 years after this specimen was collected?