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A preliminary analysis of correlated evolution in Mammalian chewing motor patterns.

Publication ,  Journal Article
Williams, SH; Vinyard, CJ; Wall, CE; Doherty, AH; Crompton, AW; Hylander, WL
Published in: Integrative and comparative biology
August 2011

Descriptive and quantitative analyses of electromyograms (EMG) from the jaw adductors during feeding in mammals have demonstrated both similarities and differences among species in chewing motor patterns. These observations have led to a number of hypotheses of the evolution of motor patterns, the most comprehensive of which was proposed by Weijs in 1994. Since then, new data have been collected and additional hypotheses for the evolution of motor patterns have been proposed. Here, we take advantage of these new data and a well-resolved species-level phylogeny for mammals to test for the correlated evolution of specific components of mammalian chewing motor patterns. We focus on the evolution of the coordination of working-side (WS) and balancing-side (BS) jaw adductors (i.e., Weijs' Triplets I and II), the evolution of WS and BS muscle recruitment levels, and the evolution of asynchrony between pairs of muscles. We converted existing chewing EMG data into binary traits to incorporate as much data as possible and facilitate robust phylogenetic analyses. We then tested hypotheses of correlated evolution of these traits across our phylogeny using a maximum likelihood method and the Bayesian Markov Chain Monte Carlo method. Both sets of analyses yielded similar results highlighting the evolutionary changes that have occurred across mammals in chewing motor patterns. We find support for the correlated evolution of (1) Triplets I and II, (2) BS deep masseter asynchrony and Triplets I and II, (3) a relative delay in the activity of the BS deep masseter and a decrease in the ratio of WS to BS muscle recruitment levels, and (4) a relative delay in the activity of the BS deep masseter and a delay in the activity of the BS posterior temporalis. In contrast, changes in relative WS and BS activity levels across mammals are not correlated with Triplets I and II. Results from this work can be integrated with dietary and morphological data to better understand how feeding and the masticatory apparatus have evolved across mammals in the context of new masticatory demands.

Duke Scholars

Published In

Integrative and comparative biology

DOI

EISSN

1557-7023

ISSN

1540-7063

Publication Date

August 2011

Volume

51

Issue

2

Start / End Page

247 / 259

Related Subject Headings

  • Phylogeny
  • Movement
  • Models, Statistical
  • Masticatory Muscles
  • Mastication
  • Mammals
  • Jaw
  • Evolutionary Biology
  • Electromyography
  • Bite Force
 

Citation

APA
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ICMJE
MLA
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Williams, S. H., Vinyard, C. J., Wall, C. E., Doherty, A. H., Crompton, A. W., & Hylander, W. L. (2011). A preliminary analysis of correlated evolution in Mammalian chewing motor patterns. Integrative and Comparative Biology, 51(2), 247–259. https://doi.org/10.1093/icb/icr068
Williams, Susan H., Christopher J. Vinyard, Christine E. Wall, Alison H. Doherty, Alfred W. Crompton, and William L. Hylander. “A preliminary analysis of correlated evolution in Mammalian chewing motor patterns.Integrative and Comparative Biology 51, no. 2 (August 2011): 247–59. https://doi.org/10.1093/icb/icr068.
Williams SH, Vinyard CJ, Wall CE, Doherty AH, Crompton AW, Hylander WL. A preliminary analysis of correlated evolution in Mammalian chewing motor patterns. Integrative and comparative biology. 2011 Aug;51(2):247–59.
Williams, Susan H., et al. “A preliminary analysis of correlated evolution in Mammalian chewing motor patterns.Integrative and Comparative Biology, vol. 51, no. 2, Aug. 2011, pp. 247–59. Epmc, doi:10.1093/icb/icr068.
Williams SH, Vinyard CJ, Wall CE, Doherty AH, Crompton AW, Hylander WL. A preliminary analysis of correlated evolution in Mammalian chewing motor patterns. Integrative and comparative biology. 2011 Aug;51(2):247–259.
Journal cover image

Published In

Integrative and comparative biology

DOI

EISSN

1557-7023

ISSN

1540-7063

Publication Date

August 2011

Volume

51

Issue

2

Start / End Page

247 / 259

Related Subject Headings

  • Phylogeny
  • Movement
  • Models, Statistical
  • Masticatory Muscles
  • Mastication
  • Mammals
  • Jaw
  • Evolutionary Biology
  • Electromyography
  • Bite Force