How do rats walk? - briefly
Rats move with a quadrupedal gait that alternates diagonal limb pairs, providing rapid and agile locomotion. Their flexible spine and precise foot placement allow swift changes in direction and speed.
How do rats walk? - in detail
Rats achieve rapid, agile locomotion through a series of coordinated limb movements and spinal adjustments. Each stride consists of a swing phase, during which the foot leaves the ground, and a stance phase, when the foot contacts the substrate and supports body weight. The forelimbs initiate the swing slightly earlier than the hindlimbs, creating a diagonal gait pattern that enhances stability on uneven surfaces.
Key characteristics of their gait include:
- High step frequency: Rats can execute up to 12 steps per second during sprinting, facilitated by short limb segments and powerful musculature.
- Extended stride length: During fast locomotion, hindlimb stride length increases proportionally to speed, while forelimb stride remains relatively constant to maintain balance.
- Dynamic spinal flexion: The lumbar spine flexes and extends rhythmically, contributing to forward thrust and allowing the tail to act as a counterbalance.
- Tail assistance: The tail oscillates in opposition to the hindlimb motion, reducing rotational torque and improving directional control.
- Paw placement precision: Sensory receptors in the pads detect substrate texture, enabling micro-adjustments that prevent slipping.
During acceleration, the duty factor—percentage of the gait cycle spent in stance—decreases, shifting the gait from a walk to a trot and eventually to a gallop at top speeds. Muscular activation patterns show early recruitment of the gastrocnemius and quadriceps to generate propulsion, followed by coordinated activation of the flexor digitorum muscles to retract the paw during swing. Electromyographic studies reveal that the central pattern generator in the spinal cord orchestrates these rhythmic bursts without requiring cortical input for each step.
Overall, rat locomotion integrates rapid limb cycling, spinal flexion, and tail dynamics to produce a versatile gait capable of navigating complex environments with speed and precision.