Last week I gave you this skinny piece of bone to have a go at identifying:
As it turns out, it was both a fairly easy one, and a difficult one at the same time. The easy bit was working out what the bone was and the family that this particular one comes from. The difficult bit was working out the species.
This bone is part of the tongue-bone (or hyoid) of a woodpecker – as everyone seems to have known, based on all the comments. More specifically, this hyoid is from a European Green Woodpecker Picus viridis Linnaeus, 1758.
If you’re not familiar with the hyoid of a woodpecker, it’s a particularly interesting structure that I have written about before (all the way back in 2012). To summarise, the tongue of woodpeckers is extremely long and has barbs, which allows the woodpecker to insert it into the holes it drills in trees to fish out insect larvae.
To help accomodate this length, the hyoid arises from the right nostril of the bird and goes around the skull and into the mouth, supporting the muscle of the tongue almost the whole way around. The tongue can then contract against the bone, which allows it to elongate significantly:
Since I first blogged about this, there has been research published that has dismissed one of the proposed functions of this unusual feature. Research suggests that it is no longer considered likely that the tongue and hyoid act like a shock-absorber to help protect the woodpecker’s brain from impacts when pecking wood. (Physiology: Woodpecker skulls are not shock absorbers: Current Biology).
This was previously a widespread idea that had gained a lot of support, but I’m not particularly surprised that it probably isn’t the case to be honest, since it didn’t make a huge amount of sense from a functional perspective. Other species of bird also wrap their hyoid around their skull in the same way, simply to accommodate long tongues, but without any need for cushioning their brain. Hummingbirds are a good example that I’ve featured on the blog before:
Shock absorbing or not, these long hyoids are fascinating features, that leave a clear mark on the skull of the birds that have them – see the wide, smooth groove over the top of the skull of the specimen that this mystery hyoid came from below (it even makes a handy place to write a museum number!):
Just to note, I thought that someone might have guessed the species based on the scale and shape of the mystery object. I noted that it was 6cm across, and with that curvature it offered a hint at the length of the skull, ruling out smaller species.
For reference, here are examples of the only woodpecker species that have been recorded in Ireland, with a scale bar to help compare sizes:
I hope you enjoyed that little update on our understanding of the weird and still wonderful woodpecker hyoid.









































