Locomotion in the fastest rodent, the mara Dolichotis patagonum (Caviomorpha; Caviidae; Dolichotinae)

KARINE SILVA CLIMACO DAS CHAGAS; ECHEVERRÍA AI; BECERRA, FEDERICO; ROCHA BARBOSA, OSCAR; VASSALLO, AI; MARIANA FIUZA DE CASTRO LOGUERCIO

Mastozoología Neotopical

SAREM

Lugar: Mendoza; Año: 2019 vol. 26 p. 65 - 79

1666-0536

Although rodents can move fast, they are in general considered non-cursorial mammals, with thenotable exception of some species within the suborder Caviomorpha which are convergent with small-sizedartiodactyls. The mara, Dolichotis patagonum (average body mass: 8 kg), is a member of the family Caviidaewhich occupies relatively open habitats in southern South America, and shows remarkable anatomical traitsassociated to fast locomotion. These include elongated limbs, especially their distal segments, a digitigrade footposture, and muscles attached near limb joints. However, its locomotor behavior is not yet well understood. Herewe focus on the mara?s locomotor kinematics, especially on the gaits performed at different speeds, and providenew data and analyses. By means of high-speed video-recordings, it was observed that maras use lateral walkat low speeds and pace at moderate speeds. By implementing half bound maras reached their maximum speedat 36 km/h, i.e. 14.3 body length/s. It was also confirmed that maras are able to perform pronking, a probablealarm or fitness signal. Kinematic parameters (e.g. duty factor; stride frequency), and comparisons of runningspeed with other caviomorph and artiodactyl species are also provided.