Cutting corners: the dynamics of turning behaviors in two primate species

ostriches did use acceleration or braking forces to control body rotation, their morphology allowed for both crossovers and sidesteps to be accomplished with minimal net acceleratory/braking force production. Moreover, body roll and ab/adduction of the leg shifted the foot position away from the turn direction, reducing the acceleratory/braking forces required to prevent under-or over-rotation and aligning the leg with the ground reaction force.

Section: Introductionsupporting

confidence: 56%

Mechanics of cutting maneuvers by ostriches (Struthio camelus)

Jindrich

Smith

Jespers

et al. 2007

“…Embracing behavioral variability within locomotor repertoires of free-ranging animals is an emerging topic among those who model the mechanics of animal performance (Dickinson et al, 2000;Alexander, 2002;Demes et al, 2006;Jindrich et al, 2007). One fundamental aspect of this variability is the ability of an organism to change its direction of travel, or maneuver through an obstacle-filled environment.…”

Section: Introductionmentioning

confidence: 99%

“…Quadrupedal animals that inhabit spatially complex arboreal habitats or mountainous areas, particularly those characterized by rugged vertical relief, may benefit from adaptations facilitating the capacity to change travel direction. Despite the seemingly integral importance of turning to locomotor performance, and despite the development of a descriptive protocol for categorizing turning behavior (Eilam, 1994;Walter, 2003;Demes et al, 2006;Jindrich et al, 2006;Jindrich et al, 2007), turning as a locomotor mode is rarely integrated into consensus frameworks for recording locomotor behavior in free-ranging animals (e.g. Prost, 1965;Hunt et al, 1996;Thorpe and Crompton, 2006).…”

Section: Introductionmentioning

confidence: 99%

Increased non-linear locomotion alters diaphyseal bone shape

Carlson

Judex

2007

Self Cite

SUMMARY Comparative studies of vertebrate morphology that link habitual locomotor activities to bone structural properties are often limited by confounding factors such as genetic variability between groups. Experimental assessment of bone's adaptive response to altered activity patterns typically involves superimposing exercise onto a normal locomotor repertoire, making a distinction between qualitative changes to locomotor repertoires and quantitative increases in activity level difficult. Here, we directly tested the hypothesis that an increase in turning activity, without the application of exercise per se, will alter femoral cross-sectional shape. Thirty day-old female BALB/cByJ mice (n=10 per group) were single-housed for 8 weeks in custom-designed cages that either accentuated linear or turning locomotion or allowed subjects to freely roam standard cages. Consistent with a lack of difference in physical activity levels between groups, there were no significant differences in body mass, femoral length, midshaft cortical area,and individual measures of mediolateral (ML) and anteroposterior (AP) bending rigidity. However, the ratio of ML to AP diaphyseal rigidity, an indicator of cross-sectional shape, was significantly greater (P<0.05) in turning subjects than in linear or control subjects. Considering that across all groups mice were genetically identical and had equivalent levels of bone quantity and physical activity, differences in femoral shape were attributed to qualitative differences in locomotor patterns (i.e. specific locomotor modes). These data indicate that increased turning can alter distribution of bone mass in the femoral diaphysis, and that turning should be considered in efforts to understand form–function relationships in vertebrates.

“…Huey and Hertz, 1982;Huey and Hertz, 1984;Vilensky et al, 1994;Farley, 1997;Irschick and Jayne, 1998;Vanhooydonck and Van Damme, 2001), substrate width (e.g. Losos and Sinervo, 1989;Sinervo and Losos, 1991;Losos et al, 1993;Losos and Irschick, 1996;Bonser, 1999;Dunbar and Badam, 2000;Schmitt, 2003;Stevens, 2003;Lammers and Biknevicius, 2004;Demes et al, 2006) and texture (e.g. Zani, 2000;Claussen et al, 2002;Dai et al, 2002;Kerdok et al, 2002;Vanhooydonck et al, 2005) have all been shown to affect locomotor performance traits in a wide range of organisms.…”

mentioning

confidence: 99%

Out on a limb: the differential effect of substrate diameter on acceleration capacity inAnolislizards

Vanhooydonck

Herrel

Irschick

2006

How animals manage to effectively move around in complex arboreal environments is intriguing. Not only may perch density and inter-perch distance vary dramatically, but when moving about on, or in between trees, animals will come across a wide range of substrates differing in inclination, texture and diameter. Since different structural elements within the arboreal habitat pose different functional demands on the locomotor system, arboreal habitats are typically regarded as complex environments that are difficult to exploit. A wide diversity of organisms, however, seems capable of doing so, and examples of arboreal species exist for most tetrapod taxa (e.g. amphibians, reptiles, birds, mammals), many of which show distinct morphological and/or behavioural specializations to an arboreal lifestyle, such as the prehensile tail in monkeys (Lemelin, 1995), toe pads in frogs (Hanna and Barnes, 1991) and geckos (e.g. Autumn and Peattie, 2002), or the walking gait and prehensile feet in chameleons (Peterson, 1984) and didelphids (e.g. Lemelin et al., 2003).However, despite these specializations, locomotor performance will not be optimized on all substrates simultaneously. For instance, differences in inclination (e.g. Huey and Hertz, 1982;Huey and Hertz, 1984;Vilensky et al., 1994;Farley, 1997;Irschick and Jayne, 1998;Vanhooydonck and Van Damme, 2001), substrate width (e.g. Losos and Sinervo, 1989;Sinervo and Losos, 1991;Losos et al., 1993;Losos and Irschick, 1996;Bonser, 1999;Dunbar and Badam, 2000;Schmitt, 2003;Stevens, 2003;Lammers and Biknevicius, 2004;Demes et al., 2006) and texture (e.g. Zani, 2000;Claussen et al., 2002;Dai et al., 2002;Kerdok et al., 2002;Vanhooydonck et al., 2005) have all been shown to affect locomotor performance traits in a wide range of organisms. Even more so, some structural elements are known to mediate performance trade-offs. Substrate size, for instance, plays a mediating role in the trade-off between stability and speed. Whereas on broad surfaces (e.g. on the ground) high sprint speed can be attained without detrimentally affecting stability, on narrow surfaces (e.g. branches) high stability leads to decreased sprint performance (Peterson, 1984;Cartmill, 1985;Losos and Sinervo, 1989; Sinervo and Losos, 1991; Losos etWe investigated how substrate diameter affects acceleration performance in three Anolis lizard species (A. sagrei, A. carolinensis and A. valencienni), representing three different ecomorphs (trunk-ground, trunk-crown, and twig, respectively). We did so by measuring maximal acceleration capacity of the three species on a broad and narrow dowel. In addition to acceleration capacity, we quantified maximal sprint speed on both dowels. Both acceleration capacity and sprint speed are affected by substrate diameter, but the way in which they are, differs among species. Acceleration capacity in the trunk-ground anole, A. sagrei, was least affected by dowel diameter, whereas it was greatly reduced on the narrow dowel in the twig anole, A. valencienni. Sprint speed on the narrow dow...