Variability in odor-modulated flight by moths

Abstract Based on previous studies of odor-modulated flight where track parameter data was lumped and averaged, the speed and orientation of the moths' movement along their flight tracks have been said to be controlled to maintain certain “preferred” values. The results from our fine-scaled analysis of this behavior show that none of the track parameters typically measured are held constant. The moths' speed along the flight track is modulated substantially and predictably: fastest along the straight legs and slowest around the turns. In addition, about half of the individuals studied progressively reduced the peak speed along the straight legs as they approached the pheromone source. While most of the track legs between the turns were directed upwind, their orientations were widely distributed, indicating no preferred direction. Small fluctuations of orientation along some straight legs suggest corrective maneuvers to stabilize flight direction about an internal set point. The visual inputs hypothesized to control steering and speed, transverse and longitudinal image flow, changed continuously during upwind flight in pheromone, but no regular relationship between them was observed. We found that the orientation of the longitudinal body axis and the direction of thrust (course angle) were only rarely coincident during upwind flight to the odor source, suggesting that moths receive sensory input which differs quantitatively from that calculated by conventional methods. Our results strongly suggest that the long-accepted hypothetical mechanisms of control for this behavior do not operate in the manner in which they have been proposed.

[1]  T. Weis-Fogh Biology and Physics of locust flight II. Flight performance of the desert locust (Schistocerca gregaria) , 1956, Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences.

[2]  J. Kennedy,et al.  Pheromone-Regulated Anemotaxis in Flying Moths , 1974, Science.

[3]  R. A. Bell,et al.  Techniques for Rearing Laboratory Colonies of Tobacco Hornworms and Pink Bollworms , 1976 .

[4]  A. Ludlow,et al.  An analysis of anemotactic zigzagging flight in male moths stimulated by pheromone , 1978 .

[5]  Ring T. Cardé,et al.  Behavioral Responses of the Gypsy Moth in a Wind Tunnel to Air-Borne Enantiomers of Disparlure , 1979 .

[6]  E. Batschelet Circular statistics in biology , 1981 .

[7]  Thomas C. Baker,et al.  The effects of pheromone concentration on the flight behaviour of the oriental fruit moth, Grapholitha molesta , 1982 .

[8]  T. Baker,et al.  Pheromone Source Location by Flying Moths: A Supplementary Non-Anemotactic Mechanism , 1982, Science.

[9]  T. Baker,et al.  Optomotor regulation of ground velocity in moths during flight to sex pheromone at different heights , 1982 .

[10]  J. Kennedy Zigzagging and casting as a programmed response to wind‐borne odour: a review , 1983 .

[11]  Thomas C. Baker,et al.  A non‐anemotactic mechanism used in pheromone source location by flying moths , 1983 .

[12]  R. Preiss,et al.  Stabilization of altitude and speed in tethered flying gypsy moth males: influence of (+) and (‐)‐disparlure , 1983 .

[13]  William J. Bell,et al.  Chemo-orientation in Walking Insects , 1984 .

[14]  D. Varjú,et al.  Localization and Orientation in Biology and Engineering , 1984, Proceedings in Life Sciences.

[15]  T. Baker,et al.  Optomotor anemotaxis polarizes self‐steered zigzagging in flying moths , 1984 .

[16]  L. Riddiford,et al.  Regulation of reproductive behaviour and egg maturation in the tobacco hawk moth, Manduca sexta , 1984 .

[17]  W. J. Bell,et al.  Comprehensive Insect Physiology, Biochemistry and Pharmacology , 1985 .

[18]  H. Wagner Flight Performance and Visual Control of Flight of the Free-Flying Housefly (Musca Domestica L.) I. Organization of the Flight Motor , 1986 .

[19]  H. Wagner Flight performance and visual control of flight of the free-flying housefly (Musca domestica L.) II. Pursuit of targets , 1986 .

[20]  T. Baker,et al.  Manoeuvres used by flying male oriental fruit moths to relocate a sex pheromone plume in an experimentally shifted wind‐field , 1987 .

[21]  T. Baker,et al.  COMPARISON OF MANOEUVRES USED BY WALKING VERSUS FLYING GRAPHOLITA MOLESTA MALES DURING PHEROMONE-MEDIATED UPWIND MOVEMENT , 1987 .

[22]  Randall Beer,et al.  Intelligence as Adaptive Behavior , 1990 .

[23]  G. Wendler,et al.  Visual Control of Compensatory Head Movements in the Sphinx Moth , 1990 .

[24]  Thomas C. Baker,et al.  The effects of unilateral antennectomy on the flight behaviour of male Heliothis virescens in a pheromone plume , 1991 .

[25]  R. Cardé,et al.  Pheromone‐mediated upwind flight of male gypsy moths, Lymantria dispar, in a forest , 1991 .

[26]  M. Gewecke,et al.  Compensation of visually simulated wind drift in the swarming flight of the desert locust (Schistocerca gregaria) , 1991 .

[27]  D. Robert,et al.  I. Head movements and the organization of correctional manoeuvres , 1992 .

[28]  Daniel Robert,et al.  II. Acoustic avoidance manoeuvres and associated head movements, compared with correctional steering , 1992 .

[29]  J. Milde,et al.  Tangential medulla neurons in the moth Manduca sexta. Structure and responses to optomotor stimuli A Neuroethology, sensory, neural, and behavioral physiology , 1993 .

[30]  E. A. Arbas,et al.  Organization of goal-oriented locomotion: pheromone-modulated flight behavior of moths , 1993 .

[31]  H. Wolf The locust tegula: significance for flight rhythm generation, wing movement control and aerodynamic force production , 1993 .

[32]  R. Cardé,et al.  Fine-scale structure of pheromone plumes modulates upwind orientation of flying moths , 1994, Nature.

[33]  T. Baker,et al.  Reiterative responses to single strands of odor promote sustained upwind flight and odor source location by moths. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[34]  Ring T. Cardé,et al.  Strategies for recontacting a lost pheromone plume: casting and upwind flight in the male gypsy moth , 1994 .

[35]  T. Baker,et al.  Behaviour of flying oriental fruit moth males during approach to sex pheromone sources , 1994 .

[36]  R. Cardé,et al.  Influence of plume structure and pheromone concentration on upwind flight of Cadra cautella males , 1995 .