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To find answers, scientists study ecological complexity of Mexican, Central American coffee plantations More at http://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=132874&WT.mc_id=USNSF_1
This is an NSF Discoveries item.
Thelytokous Parthenogenesis in the Ant Myrmecina nipponica (Hymenoptera: Formicidae).
Zoolog Sci. 2014 Sep;31(9):582-6
Authors: Masuko K
Abstract Myrmecina nipponica Wheeler is a terrestrial ant nesting chiefly in the soil in forest. It is a specialized predator of oribatid mites, but also scavenges on a broad spectrum of other arthropods. In the studied population at Cape Manazuru in central Japan, M. nipponica colonies are typically monogynous, and previous dissections of queens suggested that these individuals were not inseminated, thus suggesting these ants can reproduce via thelytokous parthenogenesis. To test for thelytokous parthenogenesis in M. nipponica the spermathecae of queens (dealate gynes) from worker-containing colonies were histologically examined in detail. All specimens examined (n = 5) had no spermatozoa in the spermatheca. In addition, a total of four colony-founding queens were reared in isolation in the laboratory to test whether non-inseminated females were capable of egg laying and to test whether female offspring emerged from this brood. In all of four culture replicates, only new workers were produced from the eggs those queens had laid and male offspring was absent. After the breeding experiment, the queens' spermathecae were histologically examined and no sperm were detected in their spermathecae. These results reveal that M. nipponica queens of the Manazuru population are capable of producing female offspring thelytokously. Sexual reproduction by typical gynes and also by intermorphs has been known from other local populations of M. nipponica; therefore, this species shows geographical polymorphism in sexuality.
PMID: 25186929 [PubMed - in process]
Comparative genomics and transcriptomics in ants provide new insights into the evolution and function of odorant binding and chemosensory proteins.
BMC Genomics. 2014 Aug 26;15(1):718
Authors: McKenzie SK, Oxley PR, Kronauer DJ
Abstract BACKGROUND: The complex societies of ants and other social insects rely on sophisticated chemical communication. Two families of small soluble proteins, the odorant binding and chemosensory proteins (OBPs and CSPs), are believed to be important in insect chemosensation. To better understand the role of these proteins in ant olfaction, we examined their evolution and expression across the ants using phylogenetics and sex- and tissue-specific RNA-seq. RESULTS: We find that subsets of both OBPs and CSPs are expressed in the antennae, contradicting the previous hypothesis that CSPs have replaced OBPs in ant olfaction. Both protein families have several highly conserved clades with a single ortholog in all eusocial hymenopterans, as well as clades with more dynamic evolution and many taxon-specific radiations. The dynamically evolving OBPs and CSPs have been hypothesized to function in chemical communication. Intriguingly, we find that seven members of the conserved clades are expressed specifically in the antennae of the clonal raider ant Cerapachys biroi, whereas only one dynamically evolving CSP is antenna specific. The orthologs of the conserved, antenna-specific C. biroi genes are also expressed in antennae of the ants Camponotus floridanus and Harpegnathos saltator, indicating that antenna-specific expression of these OBPs and CSPs is conserved across ants. Most members of the dynamically evolving clades in both protein families are expressed primarily in non-chemosensory tissues and thus likely do not fulfill chemosensory functions. CONCLUSIONS: Our results identify candidate OBPs and CSPs that are likely involved in conserved aspects of ant olfaction, and suggest that OBPs and CSPs may not rapidly evolve to recognize species-specific signals.
PMID: 25159315 [PubMed - as supplied by publisher]
Collective defence portfolios of ant hosts shift with social parasite pressure.
Proc Biol Sci. 2014 Sep 22;281(1791)
Authors: Jongepier E, Kleeberg I, Job S, Foitzik S
Abstract Host defences become increasingly costly as parasites breach successive lines of defence. Because selection favours hosts that successfully resist parasitism at the lowest possible cost, escalating coevolutionary arms races are likely to drive host defence portfolios towards ever more expensive strategies. We investigated the interplay between host defence portfolios and social parasite pressure by comparing 17 populations of two Temnothorax ant species. When successful, collective aggression not only prevents parasitation but also spares host colonies the cost of searching for and moving to a new nest site. However, once parasites breach the host's nest defence, host colonies should resort to flight as the more beneficial resistance strategy. We show that under low parasite pressure, host colonies more likely responded to an intruding Protomognathus americanus slavemaker with collective aggression, which prevented the slavemaker from escaping and potentially recruiting nest-mates. However, as parasite pressure increased, ant colonies of both host species became more likely to flee rather than to fight. We conclude that host defence portfolios shift consistently with social parasite pressure, which is in accordance with the degeneration of frontline defences and the evolution of subsequent anti-parasite strategies often invoked in hosts of brood parasites.
PMID: 25100690 [PubMed - in process]
Correction: Ants of the Genus Solenopsis Westwood 1840 (Hymenoptera: Formicidae) in the Arabian Peninsula with Description of a New Species, Solenopsis elhawagryi.
PLoS One. 2014;9(6):e101856
Authors: The PLOS ONE Staff
Abstract [This corrects the article DOI: 10.1371/journal.pone.0049485.].
PMID: 24968259 [PubMed - as supplied by publisher]
The Higher Classification of the Ant Subfamily Ponerinae (Hymenoptera: Formicidae), with a Review of Ponerine Ecology and Behavior.
Zootaxa. 2014;3817(1):1-242
Authors: Schmidt CA, Shattuck SO
Abstract The tribal and generic classification of the diverse ant subfamily Ponerinae (Hymenoptera: Formicidae) is revised to reflect recent molecular phylogenetic information and a reappraisal of ponerine morphological diversity. The monogeneric tribe Thaumatomyrmecini (Thaumatomyrmex) is newly synonymized under Ponerini (syn. nov.), and the diverse genus Pachycondyla is fragmented into 19 genera, largely along the lines of its junior synonyms: Bothroponera, Brachyponera (gen. rev.), Ectomomyrmex (gen. rev.), Euponera (gen. rev.), Hagensia (gen. rev.), Megaponera (gen. rev.), Mesoponera (gen. rev.), Neoponera (gen. rev.), Ophthalmopone (gen. rev.), Pachycondyla, Paltothyreus (gen. rev.), Pseudoneoponera (gen. rev.), Pseudoponera (gen. rev.), and 6 new genera: Austroponera (gen. nov.), Buniapone (gen. nov.), Fisheropone (gen. nov.), Mayaponera (gen. nov.), Parvaponera (gen. nov.) and Rasopone (gen. nov.). Some junior synonyms of Pachycondyla are transferred to junior synonym status under other genera: Wadeura as a junior synonym of Cryptopone (syn. nov.), and both Termitopone and Syntermitopone as junior synonyms of Neoponera (syn. nov.). A new genus, Iroponera (gen. nov.), based on the new species Iroponera odax (sp. nov.), is described from Australia. Molecular and morphological justifications for these taxonomic changes are given alongside discussions of phylogenetic relationships. Keys to the world genera of Ponerinae are provided, and morphological diagnoses and species lists are given for each genus. Finally, the available information on ponerine ecology and behavior is reviewed and synthesized.
PMID: 24943802 [PubMed - in process]
A new carpenter ant, Camponotusparabarbatus (Hymenoptera: Formicidae) from India.
Biodivers Data J. 2014;(2):e996
Authors: Bharti H, Wachkoo AA
Abstract A new species of carpenter ant, collected in the Shivalik range of Himalaya is described and illustrated based on the worker and gyne castes under the name Camponotusparabarbatus sp. n. Presence of dense, short setae on gena and ventral surface of head resembles it most to Camponotusbarbatus Roger, 1863 distributed in Southeast Asia. A regional identification key of Camponotus species is provided from the Shivalik hills of Indian Himalaya.
PMID: 24855448 [PubMed]
Selective insectivory at Toro-Semliki, Uganda: Comparative analyses suggest no 'savanna' chimpanzee pattern.
J Hum Evol. 2014 Apr 29;
Authors: Webster TH, McGrew WC, Marchant LF, Payne CL, Hunt KD
Abstract Chimpanzee (Pan troglodytes) insectivory across Africa is ubiquitous. Insects provide a significant nutritional payoff and may be important for chimpanzees in dry, open habitats with narrow diets. We tested this hypothesis at Semliki, Uganda, a long-term dry study site. We evaluated prospects for insectivory by measuring insect abundance along de novo transects and trails, monitoring social insect colonies, and surveying available raw materials for elementary technology. We determined the frequency and nature of insectivory through behavioral observation and fecal analysis. We then compared our results with those from 15 other long-term chimpanzee study sites using a cluster analysis. We found that Semliki chimpanzees are one of the most insectivorous populations studied to date in terms of frequency of consumption, but they are very selective in their insectivory, regularly consuming only weaver ants (Oecophylla longinoda) and honey and bees from hives of Apis mellifera. This selectivity obtains despite having a full range of typical prey species available in harvestable quantities. We suggest that Semliki chimpanzees may face ecological time constraints and therefore bias their predation toward prey taxa that can be quickly consumed. Geographical proximity correlated with the results of the cluster analysis, while rainfall, a relatively gross measure of environment, did not. Because broad taxonomic groups of insects were used in analyses, prey availability was unlikely to have a strong effect on this pattern. Instead, we suggest that transmission of cultural knowledge may play a role in determining chimpanzee prey selection across Africa. Further study is needed to test these hypotheses.
PMID: 24792877 [PubMed - as supplied by publisher]
Targeted Research to Improve Invasive Species Management: Yellow Crazy Ant Anoplolepis gracilipes in Samoa.
PLoS One. 2014;9(4):e95301
Authors: Hoffmann BD, Auina S, Stanley MC
Abstract Lack of biological knowledge of invasive species is recognised as a major factor contributing to eradication failure. Management needs to be informed by a site-specific understanding of the invasion system. Here, we describe targeted research designed to inform the potential eradication of the invasive yellow crazy ant Anoplolepis gracilipes on Nu'utele island, Samoa. First, we assessed the ant's impacts on invertebrate biodiversity by comparing invertebrate communities between infested and uninfested sites. Second, we investigated the timing of production of sexuals and seasonal variation of worker abundance and nest density. Third, we investigated whether an association existed between A. gracilipes and carbohydrate sources. Within the infested area there were few other ants larger than A. gracilipes, as well as fewer spiders and crabs, indicating that A. gracilipes is indeed a significant conservation concern. The timing of male reproduction appears to be consistent with places elsewhere in the world, but queen reproduction was outside of the known reproductive period for this species in the region, indicating that the timing of treatment regimes used elsewhere are not appropriate for Samoa. Worker abundance and nest density were among the highest recorded in the world, being greater in May than in October. These abundance and nest density data form baselines for quantifying treatment efficacy and set sampling densities for post-treatment assessments. The number of plants and insects capable of providing a carbohydrate supply to ants were greatest where A. gracilipes was present, but it is not clear if this association is causal. Regardless, indirectly controlling ant abundance by controlling carbohydrate supply appears to be promising avenue for research. The type of targeted, site-specific research such as that described here should be an integral part of any eradication program for invasive species to design knowledge-based treatment protocols and determine assessment benchmarks to achieve eradication.
PMID: 24736559 [PubMed - as supplied by publisher]