Palaeo Pondering is all about the little thoughts and questions that arise when reading the palaeo news of the day, which I'll share with you here. So today's pondering? Death poses interpreted as 'sleeping' poses.
I was reading a post by Brian Switek over at Dinosaur Tracking about Mei long specimens (a basal troodontid) fossilised in a 'sleeping' position, with the head and tail curled around the body (Gao et al., 2012). I don't have an issue with this hypothesis per se, but I wondered about the possibility that they were actually curled up in a resting pose, then died, while they tried to recover from disease, trauma, or infection. The sleeping pose hypothesis posits that the animal died and was rapidly buried from a sudden event like an ash fall (similar to Pompeii). My hypothesis considers non-sudden events causing death and burial, which although requires less 'luck', does not automatically make it the most correct hypothesis.
So, this may not be conclusive evidence of how dinosaurs slept, but perhaps how they rested while trying to recover from injury. It's a minor quibble, but more taphonomic and stratigraphic work needs to be done for these specimens before we can say anything conclusive about these poses (which, I should add, is also pointed out by Gao et al. (2012)).
I was reading a post by Brian Switek over at Dinosaur Tracking about Mei long specimens (a basal troodontid) fossilised in a 'sleeping' position, with the head and tail curled around the body (Gao et al., 2012). I don't have an issue with this hypothesis per se, but I wondered about the possibility that they were actually curled up in a resting pose, then died, while they tried to recover from disease, trauma, or infection. The sleeping pose hypothesis posits that the animal died and was rapidly buried from a sudden event like an ash fall (similar to Pompeii). My hypothesis considers non-sudden events causing death and burial, which although requires less 'luck', does not automatically make it the most correct hypothesis.
So, this may not be conclusive evidence of how dinosaurs slept, but perhaps how they rested while trying to recover from injury. It's a minor quibble, but more taphonomic and stratigraphic work needs to be done for these specimens before we can say anything conclusive about these poses (which, I should add, is also pointed out by Gao et al. (2012)).
Dorsal view of the Early Cretaceous (Hauterivian-Valanginian) Mei long, discovered in the lower Yixian Formation, Liaoning Province, China (Gao et al., 2012). The backbone runs along the top of the picture, with the head near the centre, and the tail curled around to touch the head.
References:
Gao, C., Morschhauser, E.M., Varricchio, D.J., Liu, J., Zhao, B. 2012. A Second Soundly Sleeping Dragon: New Anatomical Details of the Chinese Troodontid Mei long with Implications for Phylogeny and Taphonomy. PLoS ONE 7(9): e45203. doi:10.1371/journal.pone.0045203
Gao, C., Morschhauser, E.M., Varricchio, D.J., Liu, J., Zhao, B. 2012. A Second Soundly Sleeping Dragon: New Anatomical Details of the Chinese Troodontid Mei long with Implications for Phylogeny and Taphonomy. PLoS ONE 7(9): e45203. doi:10.1371/journal.pone.0045203
