Insect Nests Research Articles

Stigmergic construction and topochemical information shape ant nest architecture

The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture.

A Brazilian Social Bee Must Cultivate Fungus to Survive

The nests of social insects provide suitable microenvironments for many microorganisms as they offer stable environmental conditions and a rich source of food [1-4]. Microorganisms in turn may provide several benefits to their hosts, such as nutrients and protection against pathogens [1, 4-6]. Several examples of symbiosis between social insects and microorganisms have been found in ants and termites. These symbioses have driven the evolution of complex behaviors and nest structures associated with the culturing of the symbiotic microorganisms [5, 7, 8]. However, while much is known about these relationships in many species of ants and termites, symbiotic relationships between microorganisms and social bees have been poorly explored [3,4, 9, 10]. Here, we report the first case of an obligatory relationship between the Brazilian stingless bee Scaptotrigona depilis and a fungus of the genus Monascus (Ascomycotina). Fungal mycelia growing on the provisioned food inside the brood cell are eaten by the larva. Larvae reared invitro on sterilized larval food supplemented with fungal mycelia had a much higher survival rate (76%) compared to larvae reared under identical conditions but without fungal mycelia (8% survival). The fungus was found to originate from the material from which the brood cells are made. Since the bees recycle and transport this material between nests, fungus would be transferred to newly built cells and also to newly founded nests. This is the first report of a fungus cultivation mutualism in a social bee.

A new species of Charinus Simon, 1892 (Amblypygi, Charinidae) from termite nests in French Guiana.

The genus Charinus is represented by 51 species, distributed in all tropical regions. Their small size allows them to use a wide range of micro-habitats, from caves, litter to insect nests. The new species C. sillami sp. nov. was found into termite nests of three different species: Neocapritermes taracua, Spinitermes sp. and Embiratermes neotenicus. Only Paracharon caecus (Paleoamblypygi: Paracharontidae) was previously known to be associated with Isoptera. Eleven species of Charinus were previously known from Northern South America. Charinus sillami sp. nov. is the second species of the genus occurring in French Guiana. An updated key of Northern South-American species is provided.

Composition of the insect diet in feces of yellow-throated marten, Martes flavigula, in Jirisan National Park, South Korea

The composition of the Martes flavigula diet has been extensively studied, but little is known about its insect component. This study characterized the insect diet and insect nest materials in the feces of M. flavigula . A total of 952 fecal samples were collected in Jirisan National Park from January 2009 to November 2011, and 1379 species or taxonomic groups were identified. M. flavigula fed on insects (8.7%) and bee wax (5.0%), which comprised 2.9% and 4.4% of the dry weight of M. flavigula feces, respectively. A total of 12 insect species belonging to 8 families in 3 orders were identified. The most fre quently found insects were Hymenoptera (frequency of occurrence, FO, 89.1), including Vespa simillima simillima (FO, 37.3) and Vespula koreensis koreensis (FO, 20.0). The Vespidae constituted the majority of the insect diet in autumn when the diversity of marten’s prey was strongly reduced, probably because the numbers of social insects were sufficient for M. flavigula. In addition, the data suggest that M. flavigula attacks the nests of social wasps in late autumn when males do not have a venomous sting and new queens are less aggressive than workers. Bee wax appeared in all seasons and the highest rate was from spring to early summer. However, the remains of honeybees were not found in feces; thus, M. fla vigula presumably eats honey but not honeybees.

The HIT study: Hymenoptera Identification Test—how accurate are people at identifying stinging insects?

BackgroundStinging insects in the order Hymenoptera include bees, wasps, yellow jackets, hornets, and ants. Hymenoptera sting injuries range from localized swelling to rarely death. Insect identification is helpful in the management of sting injuries. ObjectiveTo determine the accuracy of adults in identifying stinging insects and 2 insect nests. MethodsThis was a cross-sectional, multicenter study using a picture-based survey to evaluate an individual's success at identifying honeybees, wasps, bald-face hornets, and yellow jackets. Bald-face hornet and paper wasp nest identification also was assessed in this study. ResultsSix hundred forty participants completed the questionnaire. Overall, the mean number of correct responses was 3.2 (SD 1.3) of 6. Twenty participants (3.1%) correctly identified all 6 stinging insects and nests and only 10 (1.6%) were unable to identify any of the pictures correctly. The honeybee was the most accurately identified insect (91.3%) and the paper wasp was the least correctly identified insect (50.9%). For the 6 questions regarding whether the participant had been stung in the past by any of the insects (including an unidentified insect), 91% reported being stung by at least 1. Men were more successful at identify stinging insects correctly (P = .002), as were participants stung by at least 4 insects (P = .018). ConclusionThis study supports the general perception that adults are poor discriminators in distinguishing stinging insects and nests with the exception of the honeybee. Men and those participants who reported multiple stings to at least 4 insects were more accurate overall in insect identification.

Insights on the association of American Cetoniinae beetles with ants

AbstractCetoniinae beetles (Coleoptera: Scarabaeoidea: Scarabaeidae) can occupy the nests of social insects. In many cases the beetles located within the colonies of social insects encounter a place of shelter and food resources for both adults and immatures. Despite the numerous cohabitation records, the relationship of Cetoniinae beetles with their ant hosts remains mostly unexplored. In this review we provide hypotheses explaining this ant–beetle association. A conceptual model is presented on the processes underpinning the occupation of the nest and the consequences that unfold after occupation, including: (i) death of the ant colony; (ii) death of beetles; and (iii) coexistence. We also provide an exhaustive list of American Cetoniinae beetle species found associated with ants and discuss the symbiotic relationships occurring between the beetles and their host ants.

Anomalies in insect nest structures at the Garden Well gold deposit: Investigation of mound-forming termites, subterranean termites and ants

Previous research has demonstrated that small mounds of the termite Tumulitermes tumuli (Froggatt) can successfully be used as a geochemical sample medium for detecting Au mineralization concealed beneath transported cover. This finding is in contrast to the use of large mound forming species typically targeted for exploration in northern Australia and Africa. Large areas of Australia not only have small mound forming termites present but also have subterranean termites and ants. Subterranean termites can have large nests hidden sub-surface. When foraging they sheath their food sources with soil in order to create a microclimate. Here we investigate the use of this material along with nest material from an ant species as sampling media for geochemical exploration in the Yilgarn Craton, Western Australia.Samples were collected along a transect at the Garden Well Au deposit in the Duketon Greenstone Belt of the Yilgarn Craton in Western Australia. Elevated Au concentrations (above a background level ~2ppb) were found in all 3 nest structure types over the mineralization. The mound forming termite (T. tumuli), which forms structures to 60cm in height, had up to 7.4ppb Au. The subterranean termite (Schedorhinotermes actuosus) had up to 8.4ppb, in the sheath material, and an ant species (Rhytidoponera mayri) recorded Au up to 24.4ppb, in the nest material. Vertical movement of Au, Cu and Zn from at least 1.4m deep is supported by evidence in the form of XRD studies and mineral grain counts of nests. These show vertical movement of calcite-rich fragments associated with elevated Au.This is the first investigation of the suitability of subterranean termites for use in geochemical exploration and results suggest that they and ants in the same area represent a potentially useful sample media.

Recognition of nestmate eggs in the ant Formica fusca is based on queen derived cues

Abstract Inclusive fitness benefits depend on recognizing the right individuals to interact with. Social insect nests protect themselves from non-kin intruders through nestmate recognition based on chemical cues. The recognition cues on adult individuals are from a mixture of genetic and environmental sources, but the ontogeny and use of recognition cues on eggs has not been previously assessed. We studied recognition by workers of eggs that were either nestmates or non-nestmates. and the ontogeny of recognition cues on eggs in the ant Formica fusca, a species with precise egg recognition abilities. Workers were able to discriminate among freshly laid eggs with no nest derived cues on them, and the egg surface chemicals varied among nests in these eggs, suggesting that queen derived cues are used in nestmate recognition. The results are discussed in the light of their implications on deceptive social parasite strategies and within colony conflicts.

Road-kills of the giant anteater in south-eastern Brazil: 10 years monitoring spatial and temporal determinants

Context The giant anteater, Myrmecophaga tridactyla, is a large insectivorous mammal from Cerrado which is classified as vulnerable by the IUCN‘s red list. In spite of frequent giant anteater casualties, there continues to be a lack of published data on how road and landscape attributes affect road-kill rates – information that could prove useful in guiding mitigation measures. Aims We seek to determine whether road and landscape attributes influence the incidence of road-kills of the giant anteater. Methods From February 2002 to December 2012 (except for 2004), five roads in two regions in south-eastern Brazil were surveyed twice each month by car. We recorded temporal road-kill data for the giant anteater and related spatial road variables. These variables were also recorded at regular control sites every 2 km. We also took traffic volume data on stretches of the two roads to correlate with road-kills. Key results Of the 45 anteater casualties recorded, there was a predominance of adult males. On roads MG-428 and SP-334, we found anteater road-kills were more common in the dry season, negatively correlated with traffic volume and related to the presence of native vegetation. Accordingly, road-kill sites tended to occur near the cerrado and grasslands and also appeared more frequently on some straight stretches of roadways. Although it was not shown to influence road-kill rates, topography data does point to regular overpass/underpass locations allowing population connectivity. Termitaria or ant nests were present at all road-kill sites, with 86% having signs of feeding. Conclusions Native vegetation along roadways, together with straight road design, increases the probability of anteater road-kills by 40.1%. Implications For mitigation, mowing and removing insect nests on roadsides, as well as roadside wildlife fencing in cerrado and grassland areas is suggested. Warning signs and radar to reduce vehicle speed are recommended for both human safety and anteater conservation. With regard to population connectivity, the absence of aggregated anteater road-kill data in this study meant that there were no particular crossing locations identified. However, the collected topography data do show places that could be used for roadway crossings. The measures indicated may apply to similar species and types of topography on other continents.

Actinomycetes with Antimicrobial Activity Isolated from Paper Wasp (Hymenoptera: Vespidae: Polistinae) Nests

Actinomycetes-a group of antimicrobial producing bacteria-have been successfully cultured and characterized from the nest material of diverse arthropods. Some are symbionts that produce antimicrobial chemicals found to protect nest brood and resources from pathogenic microbes. Others have no known fitness relationship with their associated insects, but have been found to produce antimicrobials in vitro. Consequently, insect nest material is being investigated as a new source of novel antimicrobial producing actinomycetes, which could be harnessed for therapeutic potential. To extend studies of actinomycete-insect associations beyond soil-substrate dwelling insects and wood boring excavators, we conducted a preliminary assessment of the actinomycetes within the nests of the paper wasp, Polistes dominulus (Christ). We found that actinomycetes were readily cultured from nest material across multiple invasive P. dominulus populations-including members of the genera Streptomyces, Micromonospora, and Actinoplanes. Thirty of these isolates were assayed for antimicrobial activity against the challenge bacteria Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Serratia marcescens, and Bacillus subtilis. Sixty percent of isolates inhibited the growth of at least one challenge strain. This study provides the first assessment of bacteria associated with nests of P. dominulus, and the first record of antimicrobial producing actinomycetes isolated from social wasps. We provide a new system to explore nest associated actinomycetes from a ubiquitous and cosmopolitan group of insects.

Propagation ofCaenorhabditis japonicain the Nest of Its Carrier Insect,Parastrachia japonensis

We demonstrated the disembarkation of the bacterial-feeding nematode Caenorhabditis japonica dauer larvae (DL) from adult Parastrachia japonensis female insects and observed the propagation of nematodes in artificial insect nests. Our results clarify the process of propagation in this nematode species and provide insights into the nematode-insect relationship. Quiescent C. japonica DL resumed their mobility only at > 99.9% relative humidity (RH) at 25°C in the presence or absence of the carrier insect. In artificial nests with > 99.9% RH, DL resumed their mobility and the number of DL on female insects decreased gradually after oviposition, although numerous DL remained on the insects. Very few DL were detected on mother insects after hatching. Nematode propagation was observed on the egg mass after hatching and on nymphal carcasses; the total number of nematodes in the nest increased dramatically after this point. These results indicate that humidity is an important factor for disembarkation of C. japonica DL and that C. japonica propagates in the nest of P. japonensis where it feeds on the remains of eggs and nymph carcasses, indicating that C. japonica and P. japonensis have a unique phoretic and necromenic association.

Accessibility in networks: A useful measure for understanding social insect nest architecture

Networks and the associated tools from graph theory have now become well-established approaches to study natural as well as human-made systems. While early studies focused on topology and connectivity, the recent literature has acknowledged the importance of the dynamical properties of these networks. Here we focus on such a dynamic measure: accessibility. It characterizes for any given movement dynamics (such as random walks) the average number of nodes that can be reached in exactly h steps (out-accessibility), or the average number of nodes from which a given node can be reached (in-accessibility). This focus on dynamics makes accessibility particularly appropriate to study movement on networks and to detect complementary properties with respect to topology-based measurements such as betweenness centrality. We apply this measure to six nests of Cubitermes termites. Their mushroom-like 3D architectures consist of chambers and connecting tunnels that can be associated to nodes and edges in a communication network. Accessibilities turn out to be particularly low in the bottom part of the nests that link them to their underground tunneling network. We interpret this result in the context of anti-predator (ants) behavior and/or as a side effect of the global nest shape.

Mixed colonies of two species of congeneric stingless bees (Hymenoptera: Apinae, Meliponini) display environmentally‐acquired and endogenously‐produced recognition signals

Nestmate recognition is fundamental for the maintenance of social organization in insect nests. It is becoming well recognized that cuticle hydrocarbons mediate the recognition process, although the origin of recognition cues in stingless bees remains poorly explored. The present study investigates the effects of endogenously‐produced and environmentally‐acquired components in cuticular hydrocarbons in stingless bees. The tests are conducted using colonies of Plebeia droryana Friese and Plebeia remota Holmberg. Recognition tests are performed with four different groups: conspecific nestmates, conspecific non‐nestmates, heterospecifics and conspecific, genetically‐related individuals that emerge in a heterospecific nest. This last group is produced by introducing brood cells of P. droryana into a P. remota colony, and the resulting adult bees are tested for acceptance 10 days after emergence. For all groups, 15 individuals are sampled for chemical analysis. The results show the acceptance of all conspecific nestmates, and the rejection of almost every conspecific non‐nestmate and every heterospecific bee. Genetically‐related individuals emerging from heterospecific nests present intermediate rejection (66.7% rejection). Chemical analysis shows that P. droryana individuals emerging in a P. remota nest have small amounts of alkene and diene isomers found in P. remota cuticle that are not found in workers from the natal nest. The data clearly show that the majority of the compounds present in P. droryana cuticle are endogenously produced, although a few unsaturated compounds are acquired from the environment, increasing the chemical differences and, consequently, the rejection percentages.

Mite species inhabiting commercial bumblebee (Bombus terrestris) nests in Polish greenhouses

Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.

Ants and xenarthrans involved in a Quaternary food web from Argentina as reflected by their fossil nests and palaeocaves

Genise, J.F. & Farina, J.L. 2011: Ants and xenarthrans involved in a Quaternary food web from Argentina as reflected by their fossil nests and palaeocaves. Lethaia, Vol. 45, pp. 411–422. Quaternary (Ensenadan stage-age) deposits of the Miramar Formation from the Buenos Aires sea coast near Mar del Plata (Argentina) are well known for bearing long horizontal tunnels produced by xenarthrans, either ground sloths or armadillos. Little known is that, in some cases, these palaeocaves cross-cut social insect nests. Nests of two studied palaeocaves can be attributed to ants based on the presence of abundant ant remains, filling of chambers and organic-rich linings. Insect remains show part of a food web composed of army ants (Neivamyrmex) preying on leaf-cutting ants (Acromyrmex), Pheidole and other soil invertebrates. The other main component of this web is represented by the xenarthrans feeding on these ants. The facultative foraging function of xenarthran palaeocaves is supported by the common record of these extended horizontal tunnel systems similar to other subterranean foraging mammals, the presence of insect nests cross-cut by them and the extended myrmecophagy among xenarthrans. Xenarthran foraging burrows, despite their high-energy cost, would have been favoured by abundance of underground ant nests during Quaternary times and harsh climate. This climate would have produced the scarcity of insects on surface and longest periods of underground activity by xenarthrans, involving the extension of shelter burrows for adult and possibly juvenile feeding. □Ant fossil nests, Argentina, Buenos Aires, food web, Quaternary, xenarthran palaeocaves.

Chemical Integration of Myrmecophilous Guests inAphaenogasterAnt Nests

Social insect nests provide a safe and favourable shelter to many guests and parasites. InAphaenogaster senilisnests many guests are tolerated. Among them we studied the chemical integration of two myrmecophile beetles,Sternocoelis hispanus(Coleoptera: Histeridae) andChitosa nigrita(Coleoptera: Staphylinidae), and a silverfish. Silverfishes bear low quantities of the host hydrocarbons (chemical insignificance), acquired probably passively, and they do not match the colony odour. Both beetle species use chemical mimicry to be accepted; they have the same specific cuticular hydrocarbon profile as their host. They also match the ant colony odour, but they keep some specificity and can be recognised by the ants as a different element.Sternocoelisare always adopted in other conspecific colonies ofA. seniliswith different delays. They are adopted in the twin speciesA. ibericabut never inA. simonelliiorA. subterranea. They are readopted easily into their mother colony after an isolation of different durations until one month. After isolation they keep their hydrocarbons quantity, showing that they are able to synthesize them. Nevertheless, their profile diverges from the host colony, indicating that they adjust it in contact with the hosts. This had never been demonstrated before in myrmecophile beetles. We suggest that the chemical mimicry ofSternocoelisis the result of a coevolution withA. seniliswith a possible cleaning symbiosis.

Egg Recognition and Social Parasitism in Formica Ants

Nests of social insects are an attractive resource in terms of nutrition and shelter and therefore targeted by a variety of pathogens and parasites that harness the resources of a host colony in their own reproductive interests. Colonies of the ants Formica fusca and F. lemani serve as hosts for mound-building Formica species, the queens of which use host colonies during colony founding. Here, we investigate whether workers of the host species can mitigate the costs imposed on them by invading parasite queens by recognizing and selectively removing eggs laid by these queens. We used behavioural assays, allowing host workers to choose between con-colonial eggs and eggs laid by the parasite species F. truncorum. We show that workers of both host species discriminate between the two types of eggs in favour of con-colonial eggs. Moreover, workers of F. fusca rejected more con-colonial eggs than F. lemani. This higher rate of error in F. fusca may reflect a greater selectivity or a greater difficulty in discriminating between the two egg types. Nevertheless, both host species removed parasite eggs at a similar rate, when these were artificially introduced into the colonies, although some eggs remained after 10 d. In addition, upon receiving parasite eggs, host workers started to lay unfertilized male-destined eggs within 6 d, thus employing an alternative pathway to gain direct fitness when the resident queen is no longer present and the colony is parasitized.

Genetic diversity of termite-egg mimicking fungi “termite balls” within the nests of termites

Antagonistic or mutualistic interactions between insects and fungi are well-known, and the mutualistic interactions of fungus-growing ants, fungus-growing termites, and fungus-gardening beetles with their respective fungal mutualists are model examples of coevolution. However, our understanding of coevolutionary interactions between insects and fungi has been based on a few model systems. Fungal mimicry of termite eggs is one of the most striking evolutionary consequences of insect–fungus associations. This novel termite–fungus interaction is a good model system to compare with the relatively well-studied systems of fungus-growing ants and termites because termite egg-mimicking fungi are protected in the nests of social insects, as are fungi cultivated by fungus-growing ants and termites. Recently, among systems of fungus-growing ants and termites, much attention has been focused on common factors including monoculture system for the ultimate evolutionary stability of mutualism. We examined the genetic diversity of termite egg-mimicking fungi within host termite nests. RFLP analysis demonstrated that termite nests were often infected by multiple strains of termite egg-mimicking fungi, in contrast to single-strain monocultures in fungus combs of fungus-growing ants and termites. Additionally, phylogenetic analyses indicated the existence of a free-living stage of the termite egg-mimicking fungus as well as frequent long-distance gene flow by spores and subsequent horizontal transmission. Comparisons of these results with previous studies of fungus-growing ants and termites suggest that the level of genetic diversity of fungal symbionts within social insect nests may be important in shaping the outcome of the coevolutionary interaction, despite the fact that the mechanism for achieving genetic diversity varies with the evolutionary histories of the component species.

Ecological and Taxonomical Perspective of Yeasts in Indonesia

In the course of ecological and taxonomical study of yeasts in Indonesia, a total of 2147 yeast isolates from 315 samples in the year 2003, 2005, 2006, and 2008 had been obtained from eight locations e.g. Liwa (Sumatera), Cibinong (Java), Cibodas (Java), Kutai (Kalimantan), Enrekang (Sulawesi), Pucak (Sulawesi), Gili and Kuta (Lombok), and Kupang (Timor).  Leaves, flowers, litters, soils, epiphytic soils, insects and insect's nests were collected for yeasts isolation.  Our molecular identification based on D1/D2 region of nuclear large-subunit rDNA and the internal transcribed spacer (ITS) regions sequence data on 525 representative isolates revealed that 306 isolates belong to 48 described species (18 genera) and 209 strains belong to 19 undescribed species (19 genera), and 10 isolates were discarded because of contamination.  Based on their substrates, litter had the highest yeasts genera (19) followed by soils (18), flowers (10), leaves (6), epiphytic soils (4), and insects and insect's nests (4).  Genera found on soils were also common on litters.  Yeasts genera found on flowers and epiphytic soils were common on leaves and litters.  The genera Aureobasidium, Cryptococcus, Pseudozyma, Rhodotorula and Sporidiobolus were found in all substrates.  Based on their locations, Kutai had the highest number of genera (15) followed by Cibodas (10), Cibinong (10), Enrekang (10), Kupang (10), Pucak (9), Liwa (7), and Lombok (7).  The genus Cryptococcus was found in all locations.  Our study shed a light to detection of many new taxa of yeasts, 41% of yeasts found in this study represented novel taxa.

Nest architecture and traffic flow: large potential effects from small structural features

1. Research on human pedestrian dynamics predicts that seemingly small architectural features of the surroundings can have large effects on the behaviour of crowds and the flow of pedestrian traffic, particularly when a crowd is panicked. This theoretical framework might usefully be applied to the study of collective movement within subterranean nests of social insects.2. We examined the rate of egress from artificial nests by alarmed Linepithema humile ants. In accord with model predictions, but counter to intuition, we found that a partially obstructed exit enhanced the average rate of escape from the nest.3. The study of traffic flows in subterranean nests is almost non‐existent, but it would be worth studying the effect of nest design elements on collective movements, given the great variety of nest forms among ants and termites.