Modulation, individual variation and the role of lingual sensory afferents in the control of prey transport in the lizard Pogona vitticeps

Most organisms feed on a variety of food items that may differ dramatically in their physical and behavioural characteristics (e.g. mobility, mass, texture, etc.). Thus the ability to modulate prey transport behaviour in accordance with the characteristics of the food appears crucial. Consequently, prey reduction and transport movements must be adjusted to the natural variation in material properties of the food, between and within feeding sequences and transport cycles. Here we describe an investigation of (1) the ability of the agamid lizard Pogona vitticeps to modulate prey transport kinematics when feeding on a range of food items differing in their physical characteristics and (2) the role of sensory feedback in controlling jaw and tongue movements by bilateral transection of the lingual trigeminal sensory afferents. Our findings demonstrate that P. vitticeps modulates the kinematics of its feeding behaviour in response to the mechanical demands imposed by different food types. In addition, transection of the trigeminal sensory afferents has an effect on the movements of jaws and tongue during transport, and increases the duration of transport cycles needed to process a given food type. However, after transection, transport cycles were still different for different food types suggesting that other sources of sensory information are also used to modulate prey transport in the lizard P. vitticeps.