Ant colonies in Denver areas: Did they affected by extreme condition?

The basic debates in science since a few years ago related issues of environmental and climate changes. Global warming huge effects in the biodiversity around the world. The classical example, an extreme condition in summer season under the pressure of climate change has a big impact on environmental especially the presence of ant colonies in Denver Colorado, USA. We know well, ant as famous social insect, strongest organism in daily work and ability adaptable in all of the environmental changes. The purpose of the research is to study the presence of ant colonies species and the impact of the environmental in Denver areas. The research was conducted in summer season (June – July 2021) in sidewalks of student’s dorm at Denver Colorado USA. The observation focused to ant species that survived around the environment. The parameter of observations: ant colonies species and their anticipated adapted in the extreme condition. The first data observation showed the dominant ant colonies identified as Tetramorium sp. (Hymenoptera: Formicidae). In the simple case effect of the extreme condition increasing soil temperature and humidity affected movement to another place, protecting them from sunlight exposure. There is the “natural real fact” why the diversity of organisms decreasing when they are under the pressure of their habitat changes. The conclusion of field observation was showed: the pavement ant (Tetramorium sp.) as the dominant ant in Denver areas. The ant colonies activities are strongest affected by the temperature of soil, humidity, and food availability. There is a need for effort in the management of the environment in the summer condition, such as: preparing to plant more plant production nectar and seeds around a nest of ant colonies.

Strong pairwise ant-plant mutualism has limited spillover effects on an ant community

Pairwise mutualisms are embedded within rich communities of co-occurring species. Mutualism by definition benefits partner species and theory predicts these effects can spill over into broader communities, with consequences for abundance, diversity, and composition. Specifically, positive feedbacks between partner species may shift competitive hierarchies and drive reductions in non-partner species. We used long-term monitoring data spanning 16 years to determine the ant partner species of tree cholla cacti (Cylindriopuntia imbricata), which reward ants with extrafloral nectar in exchange for anti-herbivore defense. We coupled these long-term data with short-term characterization of the ant community via pitfall trapping, which sampled partner and non-partner species across ten plots that varied naturally in cactus density. The long-term data revealed one dominant ant partner (Liometopum apiculatum) and two other less common partners (Crematogaster opuntiae and Forelius pruinosus). In the short-term census, the dominant ant partner occupied more cacti in plots of higher cactus density, and was also found at higher occurrence within the pitfall traps in the high cactus density plots, suggesting strong positive feedbacks that promote ant occurrence where plant partners are available. Despite the consistency of L. apiculatum partnership with cacti through time and the dominance of this partnership in areas of high cactus density, spillover effects from this mutualism appear limited. Of the common ant species, a single non-partner ant species showed a modest reduction in occurrence at high cactus density, possibly in response to increased presence of L. apiculatum. Additionally, the composition and diversity of the ant community in our plots were insensitive to cactus density variation, indicating that positive effects on the dominant ant partner did not have cascading impacts on the ant community. This study provides novel evidence that pairwise mutualisms, even those with strong positive feedbacks, may be limited in the scope of their community-level effects.

Neither ant dominance nor abundance explain ant-plant network structure in Mexican temperate forests

Background Ant-plant mutualistic networks tend to have a nested structure that contributes to their stability, but the ecological factors that give rise to this structure are not fully understood. Here, we evaluate whether ant abundance and dominance hierarchy determine the structure of the ant-plant networks in two types of vegetation: oak and grassland, in two temperate environments of Mexico: Flor del Bosque State Park (FBSP) and La Malinche National Park (MNP). We predicted that dominant and abundant ant species make up the core, and submissives, the periphery of the network. We also expected a higher specialization level in the ant trophic level than in plant trophic level due to competition among the ant species for the plant-derived resources. Methods The ant-plant interaction network was obtained from the frequency of ant-plant interactions. We calculated a dominance hierarchy index for the ants using sampling with baits and evaluated their abundance using pitfall traps. Results In MNP, the Formica spp. species complex formed the core of the network (in both the oak forest and the grassland), while in FBSP, the core species were Prenolepis imparis (oak forest) and Camponotus rubrithorax (grassland). Although these core species were dominant in their respective sites, they were not necessarily the most dominant ant species. Three of the four networks (oak forest and grassland in FBSP, and oak forest in MNP) were nested and had a higher number of plant species than ant species. Although greater specialization was observed in the ant trophic level in the two sites and vegetations, possibly due to competition with the more dominant ant species, this was not statistically significant. In three of these networks (grassland and oak forest of MNP and oak forest of FBSP), we found no correlation between the dominance hierarchy and abundance of the ant species and their position within the network. However, a positive correlation was found between the nestedness contribution value and ant dominance hierarchy in the grassland of the site FBSP, which could be due to the richer ant-plant network and higher dominance index of this community. Conclusions Our evidence suggests that ant abundance and dominance hierarchy have little influence on network structure in temperate ecosystems, probably due to the species-poor ant-plant network and a dominance hierarchy formed only by the presence of dominant and submissive species with no intermediate dominant species between them (absence of gradient in hierarchy) in these ecosystems.

Do Dominant Ants Affect Secondary Productivity, Behavior and Diversity in a Guild of Woodland Ants?

The degree to which competition by dominant species shapes ecological communities remains a largely unresolved debate. In ants, unimodal dominance–richness relationships are common and suggest that dominant species, when very abundant, competitively exclude non-dominant species. However, few studies have investigated the underlying mechanisms by which dominant ants might affect coexistence and the maintenance of species richness. In this study, we first examined the relationship between the richness of non-dominant ant species and the abundance of a dominant ant species, Formica subsericea, among forest ant assemblages in the eastern US. This relationship was hump-shaped or not significant depending on the inclusion or exclusion of an influential observation. Moreover, we found only limited evidence that F. subsericea negatively affects the productivity or behavior of non-dominant ant species. For example, at the colony-level, the size and productivity of colonies of non-dominant ant species were not different when they were in close proximity to dominant ant nests than when they were away and, in fact, was associated with increased productivity in one species. Additionally, the number of foraging workers of only one non-dominant ant species was lower at food sources near than far from dominant F. subsericea nests, while the number of foragers of other species was not negatively affected. However, foraging activity of the non-dominant ant species was greater at night when F. subsericea was inactive, suggesting a potential mechanism by which some non-dominant species avoid interactions with competitively superior species. Gaining a mechanistic understanding of how patterns of community structure arise requires linking processes from colonies to communities. Our study suggests the negative effects of dominant ant species on non-dominant species may be offset by mechanisms promoting coexistence.

Ants (Hymenoptera: Formicidae) as Potential Mechanical Vectors of Pathogenic Bacteria in a Public Hospital in the Eastern Amazon, Brazil

Studies related to ants found in hospital environments have aroused interest in their role as mechanical vectors of pathogenic microorganisms. The objective of the current research was to determine the species composition and bacterial contamination of ant species found in a public hospital in the eastern Amazonian region. Ants were captured using bait containing honey and sterilized sardines in 15 locations within the Macapá Emergency Hospital, Amapá. Ants were identified morphologically using specific keys. Bacteria were first inoculed in a Brain Heart Infusion broth and then plated on 5% Agar with blood or MacConkey media. Bacterial species were identified through biochemical procedures. In total, 9,687 ants were collected, with 69.8% from the dry season and 30.2% from the rainy season. Nine species of ants were identified belonging to three subfamilies: the Monomorium pharaonis (Linnaeus 1758) being the most common, comprising 39.2% of the total specimens. Only one ant species was found in each bait, facilitating microbiological analyses. In total, 92 bacteria isolates were identified comprising 12 species. Pseudomonas aeruginosa Schroeter 1872 (Pseudomonadales: Pseudomonadaceae) was pathogenic bacteria, most frequently isolated, comprising 10.9% of the positive samples. The most contaminated ant in the study was M. pharaonis with 38.3%. It was the dominant ant species in this hospital environment. Its wide prevalence, forage day and night of this vector in hospital facilitated bacterial contamination. The presence of bacteria on ants may be associated with the dissemination of pathogens which cause hospital infections, making pest control a necessity in these institutions.

Pengaruh Agroekosistem Pertanaman Kopi terhadap Keanekaragaman dan Kelimpahan Semut (Formicidae)

<em>Ant (Formicidae: Hymenoptera) is one of the dominant groups of insects and has significant biological and ecological properties. The presence of ants in coffee plantations plays an important role as it functions as a predator. The study aimed to investigate the effect of coffee plantation agroecosystem on the diversity and abundance of ant species. The study was conducted from February to June 2018 at Pakuwon Experimental Station. The coffee plants were divided into 4 groups, based on their locations and agroecosystems, where each group consisted of 4 observation plots. Ants sampling were taken from 15 sample plants in each plot. Observation was conducted on ants found in the stems, leaves, twigs and fruits of coffee plants. The ants were taken for 5 to 10 minutes from each plant. The differences in coffee agroecosystem were grouped based on location, altitude, coffee species, shade plant, and vegetation around the observation site. The study found 59 ant morphospecies with a total of 2,535 individuals. The dominant ant was Dolichoderus sp1. There were 4 ant species that were found in all four locations, namely Camponotus sp1., Crematogaster sp1., Dolichoderus sp1., Polyrhachis sp1. which are predatory. The analysis result showed that different coffee agroecosystem affects diversity and abundance of ants.</em>

Ants Associated to Loranthaceae in an Agroecosystem Based on Cocoa Trees in Nkolbisson (Yaounde: Cameroon)

The present study was carried out in order to identify the ant fauna and her potential role as auxiliary of an agricultural system based on cocoa trees leeched by Loranthaceae, in Nkolbisson neighborhood in Yaound&eacute; (Cameroon). The work was conducted from May to September 2015. An inventory of all woody species and the associated ant fauna was carried out beforehand, followed by an inventory of the ant fauna associated couples Theobroma cacao/Loranthaceae during periods of non-flowering, flowering and fruiting Loranthaceae. We inventoried a total of 187 plants of which 44 (23.53%) were parasitized by flowering-shrub epiphytes (Loranthaceae). Theobroma cacao (cocoa) appeared to be the most abundant species (122 plants) followed by Dacryodes edulis (16 safou trees) and Mangifera indica (15 mango trees). Three species of Loranthaceae were identified: Tapinanthus preussii (Engler) Van Tieghem and Phragmanthera capitata (Sprengel) S. Balle which both attack Theobroma cacao (cocoa tree) and Tapinanthus bangwensis (Engl.et. Krause) Denser which attacks mainly forest type trees. Five sub-families of ants (Pseudomyrmicinae, Dolychoderinae, Ponerinae, Formicinae and Myrmicinae) divided into 16 genera and 35 species were recorded throughout the agrosystem. Tetramorium acculeatum has emerged as the most dominant ant species on both T. preussii and P. capitata. Monitoring of the ant foraging activity during flowering and fruiting Loranthaceae shows they participate in the flowers fall.

Investment in reward by ant-dispersed plants consistently selects for better partners along a geographic gradient

Seed dispersal by ants (myrmecochory) is an asymmetric, presumably mutualistic interaction, where a few ant species benefit many plants. Myrmecochorous plants express specialized adaptations, most notably a large elaiosome, which promote interactions with efficient seed dispersers while decreasing interactions with poor dispersers, resulting in de facto partner choice. However, because variation in plants’ investment in reward and ant response to them may vary spatially and temporally, it is unclear whether such specialization is consistent along geographic gradients; especially towards myrmecochory’s range margin. To answer this question on context-dependent partner choice, we first estimated variation in reward investment by co-occurring myrmecochores along a steep environmental gradient in a Mediterranean region. Second, we tested whether variation in plant investment in reward was positively and consistently correlated with the quality of dispersal plant received along the same gradient. Using in situ cafeteria experiments, we simultaneously presented diaspores of locally co-occurring myrmecochorous species to ants of two guilds representing high- and low-quality dispersers. We then recorded ant-seed behaviour, seed preference and seed removal rates for each ant guild. We found both overall and within-site high variation among plant species in the total and relative investment in elaiosomes. Both ant guilds removed substantial proportion of the seeds. However, scavenging ants (high-quality dispersers) clearly preferred diaspores with larger elaiosomes, whereas granivorous ants (low-quality dispersers) exhibited no preference. Furthermore, both the variation in plant traits and the corresponding response of different ant guilds were consistent along the studied geographic gradient. This consistency holds even when granivores, which removed seeds in a non-selective fashion and provided apparently low-quality seed dispersal services, were, at least numerically, the dominant ant guild. This dominance and the consistency of the partner choice shed light on the functionality of elaiosomes at the margins of myrmecochory’s distribution.