Current Projects

Suction feeding in fishes and its influence on body diversification

Suction feeding is the oldest and most widespread feeding strategy among jawed vertebrates. Fish suction feed by rapidly expanding the buccal cavity to create a negative pressure gradient, which drives the flow of water and nearby prey items into the mouth. It has recently been shown that 95% of the power required for suction feeding in largemouth bass is generated by the axial muscles that span most of the body and also function in swimming (Camp and Brainerd 2014; Camp et al. 2015). These muscles pull on the back of the head and cause the mouth to expand through a three-dimensional linkage of mobile cranial bones. Whether locomotor muscles provide most of the power in other suction-feeding ray-finned fishes remains unknown. Additionally, if largemouth bass are representative of other suction feeding fishes, how motor coordination between cranial and postcranial functional systems has influenced the diversification of body forms among fishes also remains unknown. Read more...

Modeling musculoskeletal systems as mechanical linkages

Mechanical linkages, interconnected chains of rigid links, provide a useful model for the motion and force transmission of musculoskeletal systems, particularly for those systems in which the skeletal elements interconnect to form closed chains (or loops). Mechanical linkages have been used as models for a diversity of musculoskeletal systems, including the skulls of fishes (Westneat 1990) , some lizards (Metzger 2002), and birds (Van Gennip and Berkhoudt 1992), the rib cages of birds (Claessens 2009), and the striking appendages of mantis shrimps (Patek et al. 2007). However, previous applications of linkage modeling have predominately focused on 2D models and linkages in which all the links interconnect as a single chain, excluding a number of diverse musculoskeletal characterized by 3D motions and elements that interconnect to form multiple, nested chains (referred to in engineering as multiloop or parallel linkages). Read more...

Reconstructing the evolution of feeding in waterfowl

Bird beaks are frequently invoked as a classic example of adaptive evolution to feeding ecology. However, most studies of feeding evolution in birds have focused on Passerines, which represent only half of all avian diversity. And, with the exception of Darwin's finches, there are few bird groups in which we have an integrated understanding of how the feeding system has evolved. Waterfowl (Anseriformes) are a diverse and globally distributed order of birds that includes ducks, geese, swans, and mergansers. Owing to their economic and agricultural importance, more is known about the diets of waterfowl than perhaps any other bird order. Waterfowl also exhibit a diversity of beak shapes and feeding behaviors. For these reasons waterfowl are an ideal model system for understanding the evolution of an avian feeding system and for testing classic hypotheses on the link between beak shape and feeding ecology. Read more...