The sweet spot of a biological hammer: the centre of percussion of glyptodont (Mammalia: Xenarthra) tail clubs
- PMID: 19710060
- PMCID: PMC2825778
- DOI: 10.1098/rspb.2009.1144
The sweet spot of a biological hammer: the centre of percussion of glyptodont (Mammalia: Xenarthra) tail clubs
Abstract
The importance of the centre of percussion (CP) of some hand-held sporting equipment (such as tennis rackets and baseball bats) for athletic performance is well known. In order to avoid injuries it is important that powerful blows are located close to the CP. Several species of glyptodont (giant armoured mammals) had tail clubs that can be modelled as rigid beams (like baseball bats) and it is generally assumed that these were useful for agonistic behaviour. However, the variation in tail club morphology among known genera suggests that a biomechanical and functional analysis of these structures could be useful. Here, we outline a novel method to determine the CP of the glyptodont tail clubs. We find that the largest species had the CP very close to the possible location of horny spikes. This is consistent with the inference that they were adapted to delivering powerful blows at that point. Our new analysis reinforces the case for agonistic use of tail clubs in several glyptodont species.
Figures
References
-
- Alexander R. McN.1983Animal mechanics, 2nd edn.Oxford, UK: Blackwell
-
- Alexander R. McN., Fariña R. A., Vizcaíno S. F.1999Tail blow energy and carapace fractures in a large glyptodont (Mammalia, Xenarthra). Zool. J. Linn. Soc. 126, 41–49 (doi:10.1111/j.1096-3642.1999.tb00606.x) - DOI
-
- Bargo M. S., Vizcaíno S. F., Archuby F. M., Blanco R. E.2000Limb bone proportions, strength and digging in some Lujanian (Late Pleistocene–Early Holocene) mylodontid ground sloths (Mammalia, Xenarthra). J. Vert. Paleontol. 20, 601–610 (doi:10.1671/0272-4634(2000)020[0601:LBPSAD]2.0.CO;2) - DOI
-
- Beal B. F.1983Predation of juveniles by the hard clam Mercenaria mercenaria (Linne) by the snapping shrimp Alpheus heterochaelis Say and Alpheus normanni Kingsley. J. Shellfish Res. 3, 1–9
-
- Blanco R. E., Jones W. W.2005Terror bird on the run: a mechanical model to estimate its maximum running speed. Proc. R. Soc. B 272, 1769–1773 (doi:10.1098/rspb.2005.3133) - DOI - PMC - PubMed
MeSH terms
LinkOut - more resources
Full Text Sources
Other Literature Sources
Miscellaneous
