TY - JOUR

T1 - Evidence for a pervasive ‘idling-mode’ activity template in flying and pedestrian insects

AU - Reynolds, Andrew M.

AU - Jones, Hayley B.C.

AU - Hill, Jane K.

AU - Pearson, Aislinn J.

AU - Wilson, Kenneth

AU - Wolf, Stephan

AU - Lim, Ka S.

AU - Reynolds, Don R.

AU - Chapman, Jason W.

PY - 2015/5/20

Y1 - 2015/5/20

N2 - Understanding the complex movement patterns of animals in natural environments is a key objective of ‘movement ecology’. Complexity results from behavioural responses to external stimuli but can also arise spontaneously in their absence. Drawing on theoretical arguments about decision-making circuitry, we predict that the spontaneous patterns will be scale-free and universal, being independent of taxon and mode of locomotion. To test this hypothesis, we examined the activity patterns of the European honeybee, and multiple species of noctuid moth, tethered to flight mills and exposed to minimal external cues. We also reanalysed pre-existing data for Drosophila flies walking in featureless environments. Across these species, we found evidence of common scale-invariant properties in their movement patterns; pause and movement durations were typically power law distributed over a range of scales and characterized by exponents close to 3/2. Our analyses are suggestive of the presence of a pervasive scale-invariant template for locomotion which, when acted on by environmental cues, produces the movements with characteristic scales observed in nature. Our results indicate that scale-finite complexity as embodied, for instance, in correlatedrandom walk models, may be the result of environmental cues overriding innate behaviour, and that scale-free movements may be intrinsic and not limited to ‘blind’ foragers as previously thought.

AB - Understanding the complex movement patterns of animals in natural environments is a key objective of ‘movement ecology’. Complexity results from behavioural responses to external stimuli but can also arise spontaneously in their absence. Drawing on theoretical arguments about decision-making circuitry, we predict that the spontaneous patterns will be scale-free and universal, being independent of taxon and mode of locomotion. To test this hypothesis, we examined the activity patterns of the European honeybee, and multiple species of noctuid moth, tethered to flight mills and exposed to minimal external cues. We also reanalysed pre-existing data for Drosophila flies walking in featureless environments. Across these species, we found evidence of common scale-invariant properties in their movement patterns; pause and movement durations were typically power law distributed over a range of scales and characterized by exponents close to 3/2. Our analyses are suggestive of the presence of a pervasive scale-invariant template for locomotion which, when acted on by environmental cues, produces the movements with characteristic scales observed in nature. Our results indicate that scale-finite complexity as embodied, for instance, in correlatedrandom walk models, may be the result of environmental cues overriding innate behaviour, and that scale-free movements may be intrinsic and not limited to ‘blind’ foragers as previously thought.

KW - Behavioural bursts

KW - Intermittent locomotion

KW - Lévy flights

KW - Power-law distributions

KW - Spontaneous movement patterns

U2 - 10.1098/rsos.150085

DO - 10.1098/rsos.150085

M3 - Journal article

AN - SCOPUS:84940456760

VL - 2

JO - Royal Society Open Science

JF - Royal Society Open Science

SN - 2054-5703

IS - 5

M1 - 150085

ER -