1
|
Ant invasion is associated with lower root density and different root distribution of a foundational savanna tree species. Biol Invasions 2023. [DOI: 10.1007/s10530-023-03008-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
2
|
Liu K, Tseng S, Tatsuta H, Tsuji K, Tay J, Singham GV, Yang CS, Neoh K. Population genetic structure of the globally introduced big-headed ant in Taiwan. Ecol Evol 2022; 12:e9660. [PMID: 36582779 PMCID: PMC9789323 DOI: 10.1002/ece3.9660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 12/25/2022] Open
Abstract
Global commerce and transportation facilitate the spread of invasive species. The African big-headed ant, Pheidole megacephala (Fabricius), has achieved worldwide distribution through globalization. Since the late 19th century, Taiwan has served as a major seaport because of its strategic location. The population genetic structure of P. megacephala in Taiwan is likely to be shaped by international trade and migration between neighboring islands. In this study, we investigated the population genetics of P. megacephala colonies sampled from four geographical regions in Taiwan and elucidated the population genetic structures of P. megacephala sampled from Taiwan, Okinawa, and Hawaii. We observed a low genetic diversity of P. megacephala across regions in Taiwan. Moreover, we noted low regional genetic differentiation and did not observe isolation by distance, implying that long-distance jump dispersal might have played a crucial role in the spread of P. megacephala. We sequenced the partial cytochrome oxidase I gene and observed three mitochondrial haplotypes (TW1-TW3). TW1 and TW3 most likely originated from populations within the species' known invasive range, suggesting that secondary introduction is the predominant mode of introduction for this invasive ant. TW2 represents a novel haplotype that was previously unreported in other regions. P. megacephala populations from Taiwan, Okinawa, and Hawaii exhibited remarkable genetic similarity, which may reflect their relative geographic proximity and the historical connectedness of the Asia-Pacific region.
Collapse
Affiliation(s)
- Kuan‐Ling Liu
- Department of EntomologyNational Chung Hsing UniversityTaichungTaiwan
| | - Shu‐Ping Tseng
- Department of EntomologyNational Taiwan UniversityTaipeiTaiwan
| | - Haruki Tatsuta
- Graduate School of Systems Life SciencesKyushu UniversityFukuokaJapan
| | - Kazuki Tsuji
- Department of Subtropical Agro‐Environmental SciencesUniversity of the RyukyusOkinawaJapan
| | - Jia‐Wei Tay
- Department of Plant and Environmental Protection SciencesUniversity of Hawaii at ManoaHonoluluHawaiiUSA
| | - G. Veera Singham
- Centre for Chemical BiologyUniversiti Sains MalaysiaPenangMalaysia
| | - Chin‐Cheng Scotty Yang
- Department of EntomologyVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | - Kok‐Boon Neoh
- Department of EntomologyNational Chung Hsing UniversityTaichungTaiwan
| |
Collapse
|
3
|
Blumenfeld AJ, Eyer PA, Helms AM, Buczkowski G, Vargo EL. Consistent signatures of urban adaptation in a native, urban invader ant Tapinoma sessile. Mol Ecol 2021; 31:4832-4850. [PMID: 34551170 DOI: 10.1111/mec.16188] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/11/2021] [Accepted: 09/15/2021] [Indexed: 11/29/2022]
Abstract
Biological invasions are becoming more prevalent due to the rise of global trade and expansion of urban areas. Ants are among the most prolific invaders with many exhibiting a multiqueen colony structure, dependent colony foundation and reduced internest aggression. Although these characteristics are generally associated with the invasions of exotic ants, they may also facilitate the spread of native ants into novel habitats. Native to diverse habitats across North America, the odorous house ant Tapinoma sessile has become abundant in urban environments throughout the United States. Natural colonies typically have a small workforce, inhabit a single nest, and are headed by a single queen, whereas urban colonies tend to be several orders of magnitude larger, inhabit multiple nests (i.e., polydomy) and are headed by multiple queens (i.e., polygyny). Here, we explore and compare the population genetic and breeding structure of T. sessile within and between urban and natural environments in several localities across its distribution range. We found the social structure of a colony to be a plastic trait in both habitats, although extreme polygyny was confined to urban habitats. Additionally, polydomous colonies were only present in urban habitats, suggesting T. sessile can only achieve supercoloniality within urbanized areas. Finally, we identified strong differentiation between urban and natural populations in each locality and continent-wide, indicating cities may restrict gene flow and exert intense selection pressure. Overall, our study highlights urbanization's influence in charting the evolutionary course for species.
Collapse
Affiliation(s)
| | - Pierre-André Eyer
- Department of Entomology, TAMU, Texas A&M University, College Station, Texas, USA
| | - Anjel M Helms
- Department of Entomology, TAMU, Texas A&M University, College Station, Texas, USA
| | | | - Edward L Vargo
- Department of Entomology, TAMU, Texas A&M University, College Station, Texas, USA
| |
Collapse
|
4
|
Palmer TM, Riginos C, Milligan PD, Hays BR, Pietrek AG, Maiyo NJ, Mutisya S, Gituku B, Musila S, Carpenter S, Goheen JR. Frenemy at the gate: Invasion by Pheidole megacephala facilitates a competitively subordinate plant ant in Kenya. Ecology 2020; 102:e03230. [PMID: 33098658 DOI: 10.1002/ecy.3230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/17/2020] [Accepted: 09/14/2020] [Indexed: 11/11/2022]
Abstract
Biological invasions can lead to the reassembly of communities and understanding and predicting the impacts of exotic species on community structure and functioning are a key challenge in ecology. We investigated the impact of a predatory species of invasive ant, Pheidole megacephala, on the structure and function of a foundational mutualism between Acacia drepanolobium and its associated acacia-ant community in an East African savanna. Invasion by P. megacephala was associated with the extirpation of three extrafloral nectar-dependent Crematogaster acacia ant species and strong increases in the abundance of a competitively subordinate and locally rare acacia ant species, Tetraponera penzigi, which does not depend on host plant nectar. Using a combination of long-term monitoring of invasion dynamics, observations and experiments, we demonstrate that P. megacephala directly and indirectly facilitates T. penzigi by reducing the abundance of T. penzigi's competitors (Crematogaster spp.), imposing recruitment limitation on these competitors, and generating a landscape of low-reward host plants that favor colonization and establishment by the strongly dispersing T. penzigi. Seasonal variation in use of host plants by P. megacephala may further increase the persistence of T. penzigi colonies in invaded habitat. The persistence of the T. penzigi-A. drepanolobium symbiosis in invaded areas afforded host plants some protection against herbivory by elephants (Loxodonta africana), a key browser that reduces tree cover. However, elephant damage on T. penzigi-occupied trees was higher in invaded than in uninvaded areas, likely owing to reduced T. penzigi colony size in invaded habitats. Our results reveal the mechanisms underlying the disruption of this mutualism and suggest that P. megacephala invasion may drive long-term declines in tree cover, despite the partial persistence of the ant-acacia symbiosis in invaded areas.
Collapse
Affiliation(s)
- Todd M Palmer
- Department of Biology, University of Florida, Gainesville, Florida, 32601, USA.,Mpala Research Centre, Box 555, Nanyuki, Kenya
| | - Corinna Riginos
- The Nature Conservancy, Lander, Wyoming, 82520, USA.,Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, 82071, USA
| | - Patrick D Milligan
- Department of Biology, University of Florida, Gainesville, Florida, 32601, USA.,Mpala Research Centre, Box 555, Nanyuki, Kenya
| | - Brandon R Hays
- Mpala Research Centre, Box 555, Nanyuki, Kenya.,Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, 82071, USA
| | - Alejandro G Pietrek
- Department of Biology, University of Florida, Gainesville, Florida, 32601, USA.,Mpala Research Centre, Box 555, Nanyuki, Kenya.,Instituto de Bio y Geociencias del NOA (IBIGEO), Salta, Argentina
| | - Nelly J Maiyo
- Conservation Department, Ol Pejeta Conservancy, Private Bag-10400, Nanyuki, Kenya
| | - Samuel Mutisya
- Conservation Department, Ol Pejeta Conservancy, Private Bag-10400, Nanyuki, Kenya
| | - Benard Gituku
- Conservation Department, Ol Pejeta Conservancy, Private Bag-10400, Nanyuki, Kenya
| | - Simon Musila
- Mammalogy Section, National Museums of Kenya, Nairobi, Kenya
| | - Scott Carpenter
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut, 06520, USA
| | - Jacob R Goheen
- Mpala Research Centre, Box 555, Nanyuki, Kenya.,Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, 82071, USA
| |
Collapse
|
5
|
Hsu HW, Chiu MC, Lee CC, Lee CY, Yang CCS. The Association between Virus Prevalence and Intercolonial Aggression Levels in the Yellow Crazy Ant, Anoplolepis Gracilipes (Jerdon). INSECTS 2019; 10:insects10120436. [PMID: 31817209 PMCID: PMC6956197 DOI: 10.3390/insects10120436] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/29/2019] [Accepted: 11/30/2019] [Indexed: 01/30/2023]
Abstract
The recent discovery of multiple viruses in ants, along with the widespread infection of their hosts across geographic ranges, provides an excellent opportunity to test whether viral prevalence in the field is associated with the complexity of social interactions in the ant population. In this study, we examined whether the association exists between the field prevalence of a virus and the intercolonial aggression of its ant host, using the yellow crazy ant (Anoplolepis gracilipes) and its natural viral pathogen (TR44839 virus) as a model system. We delimitated the colony boundary and composition of A. gracilipes in a total of 12 study sites in Japan (Okinawa), Taiwan, and Malaysia (Penang), through intercolonial aggression assay. The spatial distribution and prevalence level of the virus was then mapped for each site. The virus occurred at a high prevalence in the surveyed colonies of Okinawa and Taiwan (100% infection rate across all sites), whereas virus prevalence was variable (30%–100%) or none (0%) at the sites in Penang. Coincidentally, colonies in Okinawa and Taiwan displayed a weak intercolonial boundary, as aggression between colonies is generally low or moderate. Contrastingly, sites in Penang were found to harbor a high proportion of mutually aggressive colonies, a pattern potentially indicative of complex colony composition. Our statistical analyses further confirmed the observed correlation, implying that intercolonial interactions likely contribute as one of the effective facilitators of/barriers to virus prevalence in the field population of this ant species.
Collapse
Affiliation(s)
- Hung-Wei Hsu
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan;
| | - Ming-Chung Chiu
- Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan;
| | - Ching-Chen Lee
- Center for Ecology and Environment, Department of Life Science, Tunghai University, Taichung 40704, Taiwan;
| | - Chow-Yang Lee
- Department of Entomology, University of California, Riverside, 900 University Avenue, Riverside, CA 92521, USA;
| | - Chin-Cheng Scotty Yang
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
- Correspondence: ; Tel.: +81-70-4144-2823
| |
Collapse
|
6
|
Ritualized aggressive behavior reveals distinct social structures in native and introduced range tawny crazy ants. PLoS One 2019; 14:e0225597. [PMID: 31756233 PMCID: PMC6874334 DOI: 10.1371/journal.pone.0225597] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 11/07/2019] [Indexed: 11/19/2022] Open
Abstract
How workers within an ant colony perceive and enforce colony boundaries is a defining biological feature of an ant species. Ants fall along a spectrum of social organizations ranging from single-queen, single nest societies to species with multi-queen societies in which workers exhibit colony-specific, altruistic behaviors towards non-nestmate workers from distant locations. Defining where an ant species falls along this spectrum is critical for understanding its basic ecology. Herein we quantify queen numbers, describe intraspecific aggression, and characterize the distribution of colony sizes for tawny crazy ant (Nylanderia fulva) populations in native range areas in South America as well as in their introduced range in the Southeastern United States. In both ranges, multi-queen nests are common. In the introduced range, aggressive behaviors are absent at all spatial scales tested, indicating that within the population in the Southeastern United States N. fulva is unicolonial. However, this contrasts strongly with intraspecific aggression in its South American native range. In the native range, intraspecific aggression between ants from different nests is common and ritualized. Aggression is typically one-sided and follows a stereotyped sequence of escalating behaviors that stops before actual fighting occurs. Spatial patterns of non-aggressive nest aggregation and the transitivity of non-aggressive interactions demonstrate that results of neutral arena assays usefully delineate colony boundaries. In the native range, both the spatial extent of colonies and the average number of queens encountered per nest differ between sites. This intercontinental comparison presents the first description of intraspecific aggressive behavior for this invasive ant and characterizes the variation in colony organization in the native-range, a pre-requisite to a full understanding of the origins of unicoloniality in its introduced range.
Collapse
|
7
|
Introduction history and genetic diversity of the invasive ant Solenopsis geminata in the Galápagos Islands. Biol Invasions 2018. [DOI: 10.1007/s10530-018-1769-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
8
|
Ruane S, Richards SJ, McVay JD, Tjaturadi B, Krey K, Austin CC. Cryptic and non-cryptic diversity in New Guinea ground snakes of the genus Stegonotus Duméril, Bibron and Duméril, 1854: a description of four new species (Squamata: Colubridae). J NAT HIST 2017. [DOI: 10.1080/00222933.2017.1391959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Sara Ruane
- Department of Biological Sciences, Rutgers University, Newark, NJ, USA
- Museum of Natural Science, Louisiana State University, Baton Rouge, LA, USA
| | - Stephen J. Richards
- Herpetology Department, South Australian Museum, North Terrace, Adelaide, Australia
| | - John D. McVay
- Department of Biology, Duke University, Durham, NC, USA
| | - Burhan Tjaturadi
- Center for Environmental Studies, Sanata Dharma University, Yogyakarta, Indonesia
| | - Keliopas Krey
- Department of Biology, Faculty of Mathematics and Natural Sciences, University of Papua, Manokwari, Indonesia
| | | |
Collapse
|
9
|
Ellis S, Procter DS, Buckham-Bonnett P, Robinson EJH. Inferring polydomy: a review of functional, spatial and genetic methods for identifying colony boundaries. INSECTES SOCIAUX 2016; 64:19-37. [PMID: 28255180 PMCID: PMC5310590 DOI: 10.1007/s00040-016-0534-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 11/04/2016] [Accepted: 11/06/2016] [Indexed: 06/06/2023]
Abstract
Identifying the boundaries of a social insect colony is vital for properly understanding its ecological function and evolution. Many species of ants are polydomous: colonies inhabit multiple, spatially separated, nests. Ascertaining which nests are parts of the same colony is an important consideration when studying polydomous populations. In this paper, we review the methods that are used to identify which nests are parts of the same polydomous colony and to determine the boundaries of colonies. Specifically, we define and discuss three broad categories of approach: identifying nests sharing resources, identifying nests sharing space, and identifying nests sharing genes. For each of these approaches, we review the theoretical basis, the limitations of the approach and the methods that can be used to implement it. We argue that all three broad approaches have merits and weaknesses, and provide a methodological comparison to help researchers select the tool appropriate for the biological question they are investigating.
Collapse
Affiliation(s)
- S. Ellis
- Department of Biology and York Centre for Complex Systems Analysis, University of York, York, UK
- Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - D. S. Procter
- Department of Biology and York Centre for Complex Systems Analysis, University of York, York, UK
- Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, UK
| | - P. Buckham-Bonnett
- Department of Biology and York Centre for Complex Systems Analysis, University of York, York, UK
| | - E. J. H. Robinson
- Department of Biology and York Centre for Complex Systems Analysis, University of York, York, UK
| |
Collapse
|
10
|
Procter DS, Cottrell JE, Watts K, A'Hara SW, Hofreiter M, Robinson EJH. Does cooperation mean kinship between spatially discrete ant nests? Ecol Evol 2016; 6:8846-8856. [PMID: 28035273 PMCID: PMC5192893 DOI: 10.1002/ece3.2590] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 11/26/2022] Open
Abstract
Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation.
Collapse
Affiliation(s)
- Duncan S. Procter
- York Centre for Complex Systems Analysis & Department of BiologyUniversity of YorkYorkUK
- Centre for Exercise, Nutrition and Health SciencesSchool for Policy StudiesUniversity of BristolBristolUK
| | | | | | | | - Michael Hofreiter
- Institut für Biochemie und BiologieUniversität PotsdamPotsdamGermany
| | - Elva J. H. Robinson
- York Centre for Complex Systems Analysis & Department of BiologyUniversity of YorkYorkUK
| |
Collapse
|
11
|
Milligan PD, Prior KM, Palmer TM. An invasive ant reduces diversity but does not disrupt a key ecosystem function in an
A
frican savanna. Ecosphere 2016. [DOI: 10.1002/ecs2.1502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Patrick D. Milligan
- Department of Biology University of Florida Gainesville Florida 32611 USA
- Mpala Research Centre Box 555 Nanyuki Kenya
| | - Kirsten M. Prior
- Department of Biology University of Florida Gainesville Florida 32611 USA
- Mpala Research Centre Box 555 Nanyuki Kenya
| | - Todd M. Palmer
- Department of Biology University of Florida Gainesville Florida 32611 USA
- Mpala Research Centre Box 555 Nanyuki Kenya
| |
Collapse
|
12
|
Lenoir A, Devers S, Touchard A, Dejean A. The Guianese population of the fire ant Solenopsis saevissima is unicolonial. INSECT SCIENCE 2016; 23:739-745. [PMID: 25953710 DOI: 10.1111/1744-7917.12232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/27/2015] [Indexed: 06/04/2023]
Abstract
In this study, conducted in French Guiana, a part of the native range of the fire ant Solenopsis saevissima, we compared the cuticular hydrocarbon profiles of media workers with previous results based on intraspecific aggressiveness tests. We noted a strong congruence between the two studies permitting us to delimit 2 supercolonies extending over large distances (up to 54 km), a phenomenon known as unicoloniality. Solenopsis geminata workers, taken as an out-group for cluster analyses, have a very different cuticular hydrocarbon profile. Because S. saevissima has been reported outside its native range, our conclusion is that this species has the potential to become invasive because unicoloniality (i.e., the main attribute for ants to become invasive) was shown at least for the Guianese population.
Collapse
Affiliation(s)
- Alain Lenoir
- IRBI, Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, Université François Rabelais, 37200, Tours, France.
| | - Séverine Devers
- IRBI, Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, Université François Rabelais, 37200, Tours, France
| | - Axel Touchard
- CNRS, Écologie des Forêts de Guyane (UMR CNRS 8172), Campus agronomique, BP 316, 97379, Kourou cedex, France
| | - Alain Dejean
- CNRS, Écologie des Forêts de Guyane (UMR CNRS 8172), Campus agronomique, BP 316, 97379, Kourou cedex, France
- Université de Toulouse, UPS, INP, Ecolab, 118 route de Narbonne, 31062, Toulouse and CNRS, Ecolab (UMR-CNRS 5245), 31062, Toulouse, France
| |
Collapse
|
13
|
Social Structure and Genetic Distance Mediate Nestmate Recognition and Aggressiveness in the Facultative Polygynous Ant Pheidole pallidula. PLoS One 2016; 11:e0156440. [PMID: 27243627 PMCID: PMC4886963 DOI: 10.1371/journal.pone.0156440] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 05/13/2016] [Indexed: 11/19/2022] Open
Abstract
In social insects, the evolutionary stability of cooperation depends on the privileged relationships between individuals of the social group, which is facilitated by the recognition of relatives. Nestmate recognition is based on genetically determined cues and/or environmentally derived chemical components present on the cuticle of individuals. Here, we studied nestmate recognition in the ant Pheidole pallidula, a species where both single-queen (monogyne) and multiple-queen (polygyne) colonies co-occur in the same population. We combined geographical, genetic and chemical analyses to disentangle the factors influencing the level of intraspecific aggressiveness. We show that encounters between workers from neighbouring colonies (i.e., nests less than 5 m away) are on average less aggressive than those between workers from more distant colonies. Aggressive behaviour is associated with the level of genetic difference: workers from monogyne colonies are more aggressive than workers from polygyne colonies, and the intensity of aggressiveness is positively associated with the genetic distance between colonies. Since the genetic distance is correlated with the spatial distance between pairs of colonies, the lower level of aggression toward neighbours may result from their higher relatedness. In contrast, the analysis of overall cuticular hydrocarbon profiles shows that aggressive behaviour is associated neither with the chemical diversity of colonies, nor with the chemical distances between them. When considering methyl-branched alkanes only, however, chemical distances differed between monogyne and polygyne colonies and were significantly associated with aggressiveness. Altogether, these results show that the social structure of colonies and the genetic distances between colonies are two major factors influencing the intensity of agonistic behaviours in the ant P. pallidula.
Collapse
|
14
|
Riginos C, Karande MA, Rubenstein DI, Palmer TM. Disruption of a protective ant-plant mutualism by an invasive ant increases elephant damage to savanna trees. Ecology 2015; 96:654-61. [PMID: 26236862 DOI: 10.1890/14-1348.1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Invasive species can indirectly affect ecosystem processes via the disruption of mutualisms. The mutualism between the whistling thorn acacia (Acacia drepanolobium) and four species of symbiotic ants is an ecologically important one; ants strongly defend trees against elephants, which can otherwise have dramatic impacts on tree cover. In Laikipia, Kenya, the invasive big-headed ant (Pheidole megacephala) has established itself at numerous locations within the last 10-15 years. In invaded areas on five properties, we found that three species of symbiotic Crematogaster ants were virtually extirpated, whereas Tetraponera penzigi co-occurred with P. megacephala. T. penzigi appears to persist because of its nonaggressive behavior; in a whole-tree translocation experiment, Crematogaster defended host trees against P. megacephala, but were extirpated from trees within hours. In contrast, T. penzigi retreated into domatia and withstood invading ants for >30 days. In the field, the loss of defensive Crematogaster ants in invaded areas led to a five- to sevenfold increase in the number of trees catastrophically damaged by elephants compared to uninvaded areas. In savannas, tree cover drives many ecosystem processes and provides essential forage for many large mammal species; thus, the invasion of big-headed ants may strongly alter the dynamics and diversity of East Africa's whistling thorn savannas by disrupting this system's keystone acaciaant mutualism.
Collapse
|
15
|
Dejean A, Corbara B, Céréghino R, Leponce M, Roux O, Rossi V, Delabie JHC, Compin A. Traits allowing some ant species to nest syntopically with the fire ant Solenopsis saevissima in its native range. INSECT SCIENCE 2015; 22:289-294. [PMID: 25813245 DOI: 10.1111/1744-7917.12078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/29/2013] [Indexed: 06/04/2023]
Abstract
Supercolonies of the red fire ant Solenopsis saevissima (Smith) develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant species were repeatedly noted as nesting in close vicinity to its mounds. Here, we verified if a shared set of biological, ecological, and behavioral traits might explain how these 8 species are able to nest in the presence of S. saevissima. We did not find this to be the case. We did find, however, that all of them are able to live in disturbed habitats. It is likely that over the course of evolution each of these species acquired the capacity to live syntopically with S. saevissima through its own set of traits, where colony size (4 species develop large colonies), cuticular compounds which do not trigger aggressiveness (6 species) and submissive behaviors (4 species) complement each other.
Collapse
Affiliation(s)
- Alain Dejean
- CNRS, Écologie des Forêts de Guyane (UMR-CNRS 8172), Campus agronomique, BP 316, 97387 Kourou cedex; Université de Toulouse; UPS, INP, Ecolab, 118 route de Narbonne, 31062, Toulouse
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Robinson EJ. Polydomy: the organisation and adaptive function of complex nest systems in ants. CURRENT OPINION IN INSECT SCIENCE 2014; 5:37-43. [PMID: 32846740 DOI: 10.1016/j.cois.2014.09.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 06/11/2023]
Abstract
Many ant species spread their colonies between multiple spatially separated but socially connected nests, a phenomenon known as polydomy. Polydomous species are ecologically and phylogenetically diverse, and often economically significant as invasive pests. Benefits of polydomy may include risk spreading, efficient resource exploitation and ergonomic factors. Very little is known about the costs of polydomy; facultatively polydomous species are good candidates for identifying costs. Analysing polydomous colony structure provides insights into which costs and benefits are driving the colony organisation; for example, a cross-species analysis of inter-nest trail networks shows structural features related to long-distance transport efficiency. Deeper understanding of polydomy will shed light on key issues in evolutionary and behavioural ecology, and also benefit both conservation and pest control.
Collapse
Affiliation(s)
- Elva Jh Robinson
- Department of Biology, University of York, Heslington, York YO10 5DD, UK.
| |
Collapse
|
17
|
Wills BD, Moreau CS, Wray BD, Hoffmann BD, Suarez AV. Body size variation and caste ratios in geographically distinct populations of the invasive big-headed ant,Pheidole megacephala(Hymenoptera: Formicidae). Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12386] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bill D. Wills
- Department of Animal Biology; University of Illinois; 515 Morrill Hall, 505 S. Goodwin Ave. Urbana IL 61801 USA
| | - Corrie S. Moreau
- Department of Science and Education; Center for Integrative Research; Field Museum of Natural History; 1400 South Lake Shore Drive Chicago IL 60605 USA
| | - Brian D. Wray
- Department of Science and Education; Center for Integrative Research; Field Museum of Natural History; 1400 South Lake Shore Drive Chicago IL 60605 USA
| | - Benjamin D. Hoffmann
- CSIRO Land and Water Flagship, Tropical Ecosystems Research Centre; PMB 44 Winnellie NT 0822 Australia
| | - Andrew V. Suarez
- Department of Animal Biology; University of Illinois; 515 Morrill Hall, 505 S. Goodwin Ave. Urbana IL 61801 USA
- Program in Ecology, Evolution and Conservation Biology; Department of Entomology; University of Illinois; 320 Morrill Hall, 505 S. Goodwin Ave. Urbana IL 61801 USA
| |
Collapse
|
18
|
How to coexist with fire ants: The roles of behaviour and cuticular compounds. Behav Processes 2013; 98:51-7. [DOI: 10.1016/j.beproc.2013.04.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/20/2013] [Accepted: 04/23/2013] [Indexed: 11/21/2022]
|