Levers and linkages: mechanical trade-offs in a power-amplified system.

Journal Article (Journal Article)

Mechanical redundancy within a biomechanical system (e.g., many-to-one mapping) allows morphologically divergent organisms to maintain equivalent mechanical outputs. However, most organisms depend on the integration of more than one biomechanical system. Here, we test whether coupled mechanical systems follow a pattern of amplification (mechanical changes are congruent and evolve toward the same functional extreme) or independence (mechanisms evolve independently). We examined the correlated evolution and evolutionary pathways of the coupled four-bar linkage and lever systems in mantis shrimp (Stomatopoda) ultrafast raptorial appendages. We examined models of character evolution in the framework of two divergent groups of stomatopods-"smashers" (hammer-shaped appendages) and "spearers" (bladed appendages). Smashers tended to evolve toward force amplification, whereas spearers evolved toward displacement amplification. These findings show that coupled biomechanical systems can evolve synergistically, thereby resulting in functional amplification rather than mechanical redundancy.

Full Text

Duke Authors

Cited Authors

  • Anderson, PSL; Claverie, T; Patek, SN

Published Date

  • July 2014

Published In

Volume / Issue

  • 68 / 7

Start / End Page

  • 1919 - 1933

PubMed ID

  • 24635148

Electronic International Standard Serial Number (EISSN)

  • 1558-5646

International Standard Serial Number (ISSN)

  • 0014-3820

Digital Object Identifier (DOI)

  • 10.1111/evo.12407


  • eng