Nest complexity, group size and brood rearing in the fire ant, Solenopsis invicta

Cassill, Deby L.; Tschinkel, Wälter R.; Vinson, S. Bradleigh

doi:10.1007/s00040-002-8296-9

Cited by 66 publications

(52 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Moreover, tunnels constructed in the laboratory and observed in X-ray CT were similar in diameter to tunnels found in natural fire ant nest mounds (4.4 mm) (46), nest entranceways (3-4 mm) (45), and incipient nests (3.1 ± 0.1 mm) (47), although tunnels deeper within natural nests may be larger in size (6.0 ± 3.0 mm) (46). Our results demonstrate that during tunnel founding, fire ants show a relatively fixed behavioral program by building tunnels of approximately the same diameter in a variety of conditions.…”

Section: Resultssupporting

confidence: 66%

Climbing, falling, and jamming during ant locomotion in confined environments

Gravish¹,

Monaenkova²,

Goodisman

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Locomotion emerges from effective interactions of an individual with its environment. Principles of biological terrestrial locomotion have been discovered on unconfined vertical and horizontal substrates. However, a diversity of organisms construct, inhabit, and move within confined spaces. Such animals are faced with locomotor challenges including limited limb range of motion, crowding, and visual sensory deprivation. Little is known about how these organisms accomplish their locomotor tasks, and such environments challenge human-made devices. To gain insight into how animals move within confined spaces, we study the locomotion of the fire ant Solenopsis invicta, which constructs subterranean tunnel networks (nests). Laboratory experiments reveal that ants construct tunnels with diameter, D, comparable to body length, L = 3.5 ± 0.5 mm. Ants can move rapidly (> 9 bodylengths per s) within these environments; their tunnels allow for effective limb, body, and antennae interaction with walls, which facilitate rapid slip-recovery during ascending and descending climbs. To examine the limits of slip-recovery in artificial tunnels, we perform perturbations consisting of rapid downward accelerations of the tunnels, which induce falls. Below a critical tunnel diameter, D s = 1.31 ± 0.02 L, falls are always arrested through rapid interaction of appendages and antennae with tunnel walls to jam the falls. D s is comparable to the size of incipient nest tunnels (D = 1.06 ± 0.23 L), supporting our hypothesis that fire ants construct environments that simplify their control task when moving through the nest, likely without need for rapid nervous system intervention.animal locomotion | extended phenotype | locomotion control | social insect | stability T errestrial animals and increasingly robots must move in diverse and complex environments, including running across flat landscapes (1), swimming in sand (2), climbing rough or smooth vertical surfaces (3), and squirming through cracks (4). The bulk of discoveries of locomotor behaviors and control strategies have been made by challenging animals in the laboratory in simplified environments that are typically featureless, flat, and unconfined (5). Such simplifications have allowed discovery of general principles in locomotor modes of walking, running, and climbing (6-9). Recent studies have generated appreciation for the importance of mechanical interactions with the environment, and through biological experiment (10) and robot modeling (11,12) have demonstrated that stable and robust movement can emerge as a result of appropriately tuned dynamics of limb-ground interaction (13,14). For example, rapid perturbations to locomotion may be corrected by so-called "preflexes" (15) in which mechanical design of the limb and appropriate kinematics enable rapid recovery from perturbation (6,8,10). However, typical substrates that legged locomotors contend with differ in orientation, can deform in response to foot/body contact (1, 11), and are rough on multiple size scales (16, 17); litt...

show abstract

Section: Resultssupporting

confidence: 66%

Climbing, falling, and jamming during ant locomotion in confined environments

Gravish¹,

Monaenkova²,

Goodisman

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…It has been shown that the coupling between amplification mechanisms modulated by the group size and such environmental templates may lead to very different patterns or dynamics (10,15,23,25). This template effect of gravity may account for the formation of ellipsoidal chambers or of vertical tunnels (7,9,12,20).…”

Section: Discussionmentioning

confidence: 99%

“…Most research describes final nest structures (7,9,12) or focuses on particular digging behaviors (13,14) but provides few insights on the building process as a whole or on the mechanisms that generate a diversity of nest shapes.…”

mentioning

confidence: 99%

Shape transition during nest digging in ants

Toffin

Paolo

Campo

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Nest building in social insects is among the collective processes that show highly conservative features such as basic modules (chambers and galleries) or homeostatic properties. Although ant nests share common characteristics, they exhibit a high structural variability, of which morphogenesis and underlying mechanisms remain largely unknown. We conducted two-dimensional nestdigging experiments under homogeneous laboratory conditions to investigate the shape diversity that emerges only from digging dynamics and without the influence of any environmental heterogeneity. These experiments revealed that, during the excavation, a morphological transition occurs because the primary circular cavity evolves into a ramified structure through a branching process. Such a transition is observed, whatever the number of ants involved, but occurs more frequently for a larger number of workers. A stochastic model highlights the central role of density effects in shape transition. These results indicate that nest digging shares similar properties with various physical, chemical, and biological systems. Moreover, our model of morphogenesis provides an explanatory framework for shape transitions in decentralized growing structures in group-living animals.self-organization | nest building | branching pattern | modeling | collective behavior T he building of structures by animals is a widely spread phenomenon, from protozoa to primates (1). These structures can be considered an extension of the animal body: They have an adaptive value by improving the regulation of energetic exchanges with the outer environment (2), by ensuring the management of waste compounds (3), and by allowing food storage or protection against predation, but also by shaping the spatial distribution of social interactions (4). The nests of social insects take over all of these functions and show a robust relationship between nest volume and colony size (5-9). In ants, every nest is made of the same basic building modules (9-11) (i.e. chambers, tunnels), the sameness of which contrasts with the diversity of nest architecture (number and proportion of different modules, nest topology, and pattern regularity) that varies not only interspecifically but also intraspecifically according to the colony growth process (7, 9).Although a dynamic study of nest building is essential to understand how the diversity of patterns is generated, there are few such studies (5, 6) addressing this issue. Most research describes final nest structures (7, 9, 12) or focuses on particular digging behaviors (13, 14) but provides few insights on the building process as a whole or on the mechanisms that generate a diversity of nest shapes.The prevailing questions, therefore, are: Does the shape diversity find its origin in the complexity of the building behaviors of the insects, a specific behavior being associated to a specific shape or in quantitative changes in digging activity? Does it result from changes in the insect environment due to the building process itself? Or does the nest pa...

show abstract

“…The subterranean nests of ants show a wide diversity of patterns ranging from highly stereotyped structures (Tschinkel 2003(Tschinkel , 2004(Tschinkel , 2005 to apparently highly disorganized ones (Cassill et al 2002). However, we have recently shown (Toffin et al 2009) that a characteristic sequence of events occurs during nest excavation in ants.…”

Section: Introductionmentioning

confidence: 88%

Excavated substrate modulates growth instability during nest building in ants

2010

View full text Add to dashboard Cite

In social insects, the nests of the same species can show a large difference in size and shape. Despite these large variations, the nests share the same substructures, some appearing during nest growth. In ants, the interplay between nest size and digging activity leads to two successive morphological transitions from circular to branched shapes (budding along the perimeter of the circular cavity and tunnelling of the galleries). Like several other self-organized collective behaviours, this phenomenon, as well as the entire nest-digging process, is thought to be modulated by environmental properties. The present study investigates the effect of excavated substrate on the nest morphogenesis and the morphological transitions by using two materials with different cohesions. Here, we show that the two morphological transitions occur more frequently with a cohesive substrate than with a granular one: 96 per cent of cohesive experiments showed both transitions, whereas only 50 per cent did in granular experiments. We found that transitions and excavation cessation follow area -response thresholds: the shape transitions take place and the digging activity stops when the dug area reaches the corresponding threshold values. The shape transition thresholds are lower with the cohesive substrate and that of stopping digging is independent of nest shape and material. According to simulations, the experimental frequencies of transitions found their origin in the competition between transitions and activity cessation and in the difference between the transition threshold values of each substrate. Our results demonstrate how the substrate properties modulate the collective response and lead to various patterns. Considering the non-specific mechanisms at work, such effects of substrate coarseness have their counterparts in various collective behaviours, generating alternative patterns to colonize and exploit the environment.

show abstract

Nest complexity, group size and brood rearing in the fire ant, Solenopsis invicta

Cited by 66 publications

References 22 publications

Climbing, falling, and jamming during ant locomotion in confined environments

Climbing, falling, and jamming during ant locomotion in confined environments

Shape transition during nest digging in ants

Excavated substrate modulates growth instability during nest building in ants

Contact Info

Product

Resources

About