Moussab/ORKG-training-evaluation-set huggingface dataset:
Research field: Ecology and Evolutionary Biology
Title: Variation in morphological characters of two invasive leafminers, Liriomyza huidobrensis and L. sativae, across a tropical elevation gradient
Abstract: Abstract Changes in morphological traits along elevation and latitudinal gradients in ectotherms are often interpreted in terms of the temperature-size rule, which states that the body size of organisms increases under low temperatures, and is therefore expected to increase with elevation and latitude. However other factors like host plant might contribute to spatial patterns in size as well, particularly for polyphagous insects. Here elevation patterns for trait size and shape in two leafminer species are examined, Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae) and L. sativae Blanchard, along a tropical elevation gradient in Java, Indonesia. Adult leafminers were trapped from different locations in the mountainous area of Dieng in the province of Central Java. To separate environmental versus genetic effects, L. huidobrensis originating from 1378 m and 2129 m ASL were reared in the laboratory for five generations. Size variation along the elevation gradient was only found in L. huidobrensis and this followed expectations based on the temperature-size rule. There were also complex changes in wing shape along the gradient. Morphological differences were influenced by genetic and environmental effects. Findings are discussed within the context of adaptation to different elevations in the two species.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Widespread association of the invasive ant Solenopsis invicta with an invasive mealybug
Abstract: Factors such as aggressiveness and adaptation to disturbed environments have been suggested as important characteristics of invasive ant species, but diet has rarely been considered. However, because invasive ants reach extraordinary densities at introduced locations, increased feeding efficiency or increased exploitation of new foods should be important in their success. Earlier studies suggest that honeydew produced by Homoptera (e.g., aphids, mealybugs, scale insects) may be important in the diet of the invasive ant species Solenopsis invicta. To determine if this is the case, we studied associations of S. invicta and Homoptera in east Texas and conducted a regional survey for such associations throughout the species' range in the southeast United States. In east Texas, we found that S. invicta tended Ho- moptera extensively and actively constructed shelters around them. The shelters housed a variety of Homoptera whose frequency differed according to either site location or season, presumably because of differences in host plant availability and temperature. Overall, we estimate that the honeydew produced in Homoptera shelters at study sites in east Texas could supply nearly one-half of the daily energetic requirements of an S. invicta colony. Of that, 70% may come from a single species of invasive Homoptera, the mealybugAntonina graminis. Homoptera shelters were also common at regional survey sites and A. graminis occurred in shelters at nine of 11 survey sites. A comparison of shelter densities at survey sites and in east Texas suggests that our results from east Texas could apply throughout the range of S. invicta in the southeast United States. Antonina graminis may be an ex- ceptionally important nutritional resource for S. invicta in the southeast United States. While it remains largely unstudied, the tending of introduced or invasive Homoptera also appears important to other, and perhaps all, invasive ant species. Exploitative or mutually beneficial associations that occur between these insects may be an important, previously unrecognized factor promoting their success.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Invasional 'meltdown' on an oceanic island
Abstract: Islands can serve as model systems for understanding how biological invasions affect community structure and ecosystem function. Here we show invasion by the alien crazy ant Anoplolepis gracilipes causes a rapid, catastrophic shift in the rain forest ecosystem of a tropical oceanic island, affecting at least three trophic levels. In invaded areas, crazy ants extirpate the red land crab, the dominant endemic consumer on the forest floor. In doing so, crazy ants indirectly release seedling recruitment, enhance species richness of seedlings, and slow litter breakdown. In the forest canopy, new associations between this invasive ant and honeydew-secreting scale insects accelerate and diversify impacts. Sustained high densities of foraging ants on canopy trees result in high population densities of hostgeneralist scale insects and growth of sooty moulds, leading to canopy dieback and even deaths of canopy trees. The indirect fallout from the displacement of a native keystone species by an ant invader, itself abetted by introduced/cryptogenic mutualists, produces synergism in impacts to precipitate invasional meltdown in this system.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Collapse of ant-scale mutualism in a rainforest on Christmas Island
Abstract: Positive interactions play a widespread role in facilitating biological invasions. Here we use a landscape-scale ant exclusion experiment to show that widespread invasion of tropical rainforest by honeydew-producing scale insects on Christmas Island (Indian Ocean) has been facilitated by positive interactions with the invasive ant Anoplolepis gracilipes. Toxic bait was used to exclude A. gracilipes from large (9-35 ha) forest patches. Within 11 weeks, ant activity on the ground and on trunks had been reduced by 98-100%, while activity on control plots remained unchanged. The exclusion of ants caused a 100% decline in the density of scale insects in the canopies of three rainforest trees in 12 months (Inocarpus fagifer, Syzygium nervosum and Barringtonia racemosa), but on B. racemosa densities of scale insects also declined in control plots, resulting in no effect of ant exclusion on this species. This study demonstrates the role of positive interactions in facilitating biological invasions, and supports recent models calling for greater recognition of the role of positive interactions in structuring ecological communities.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Exploitative competition between invasive herbivores benefits a native host plant
Abstract: Although biological invasions are of considerable concern to ecologists, relatively little attention has been paid to the potential for and consequences of indirect interactions between invasive species. Such interactions are generally thought to enhance invasives' spread and impact (i.e., the "invasional meltdown" hypothesis); however, exotic species might also act indirectly to slow the spread or blunt the impact of other invasives. On the east coast of the United States, the invasive hemlock woolly adelgid (Adelges tsugae, HWA) and elongate hemlock scale (Fiorinia externa, EHS) both feed on eastern hemlock (Tsuga canadensis). Of the two insects, HWA is considered far more damaging and disproportionately responsible for hemlock mortality. We describe research assessing the interaction between HWA and EHS, and the consequences of this interaction for eastern hemlock. We conducted an experiment in which uninfested hemlock branches were experimentally infested with herbivores in a 2 x 2 factorial design (either, both, or neither herbivore species). Over the 2.5-year course of the experiment, each herbivore's density was approximately 30% lower in mixed- vs. single-species treatments. Intriguingly, however, interspecific competition weakened rather than enhanced plant damage: growth was lower in the HWA-only treatment than in the HWA + EHS, EHS-only, or control treatments. Our results suggest that, for HWA-infested hemlocks, the benefit of co-occurring EHS infestations (reduced HWA density) may outweigh the cost (increased resource depletion).
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Mutualism between fire ants and mealybugs reduce lady beetle predation
Abstract: ABSTRACT Solenopsis invicta Buren is an important invasive pest that has a negative impact on biodiversity. However, current knowledge regarding the ecological effects of its interaction with honeydewproducing hemipteran insects is inadequate. To partially address this problem, we assessed whether the interaction between the two invasive species S. invicta and Phenacoccus solenopsis Tinsley mediated predation of P. solenopsis by Propylaea japonica Thunbery lady beetles using field investigations and indoor experiments. S. invicta tending significantly reduced predation by the Pr. japonica lady beetle, and this response was more pronounced for lady beetle larvae than for adults. A field investigation showed that the species richness and quantity of lady beetle species in plots with fire ants were much lower than in those without fire ants. In an olfaction bioassay, lady beetles preferred to move toward untended rather than tended mealybugs. Overall, these results suggest that mutualism between S. invicta and P. solenopsis may have a serious impact on predation of P. solenopsis by lady beetles, which could promote growth of P. solenopsis populations.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Biological control attempts by introductions against pest insects in the field in Canada
Abstract: This is an analysis of the attempts to colonize at least 208 species of parasites and predators on about 75 species of pest insects in the field in Canada. There was colonization by about 10% of the species that were introduced in totals of under 5,000 individuals, 40% of those introduced in totals of between 5,000 and 31,200, and 78% of those introduced in totals of over 31,200. Indications exist that initial colonizations may be favoured by large releases and by selection of release sites that are semi-isolated and not ecologically complex but that colonizations are hindered when the target species differs taxonomically from the species from which introduced agents originated and when the release site lacks factors needed for introduced agents to survive or when it is subject to potentially-avoidable physical disruptions. There was no evidence that the probability of colonization was increased when the numbers of individuals released were increased by laboratory propagation. About 10% of the attempts were successful from the economic viewpoint. Successes may be overestimated if the influence of causes of coincidental, actual, or supposed changes in pest abundance are overlooked. Most of the successes were by two or more kinds of agents of which at least one attacked species additional to the target pests. Unplanned consequences of colonization have not been sufficiently harmful to warrant precautions to the extent advocated by Turnbull and Chant but are sufficiently potentially dangerous to warrant the restriction of all colonization attempts to biological control experts. It is concluded that most failures were caused by inadequate procedures, rather than by any weaknesses inherent in the method, that those inadequacies can be avoided in the future, and therefore that biological control of pest insects has much unrealized potential for use in Canada.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: The role of opportunity in the unintentional introduction of nonnative ants
Abstract: A longstanding goal in the study of biological invasions is to predict why some species are successful invaders, whereas others are not. To understand this process, detailed information is required concerning the pool of species that have the opportunity to become established. Here we develop an extensive database of ant species unintentionally transported to the continental United States and use these data to test how opportunity and species-level ecological attributes affect the probability of establishment. This database includes an amount of information on failed introductions that may be unparalleled for any group of unintentionally introduced insects. We found a high diversity of species (232 species from 394 records), 12% of which have become established in the continental United States. The probability of establishment increased with the number of times a species was transported (propagule pressure) but was also influenced by nesting habit. Ground nesting species were more likely to become established compared with arboreal species. These results highlight the value of developing similar databases for additional groups of organisms transported by humans to obtain quantitative data on the first stages of the invasion process: opportunity and transport.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Ecological biogeography of southern oceanic islands: species-area relationships, human impacts, and conservation
Abstract: Previous studies have concluded that southern ocean islands are anomalous because past glacial extent and current temperature apparently explain most variance in their species richness. Here, the relationships between physical variables and species richness of vascular plants, insects, land and seabirds, and mammals were reexamined for these islands. Indigenous and introduced species were distinguished, and relationships between the latter and human occupancy variables were investigated. Most variance in indigenous species richness was explained by combinations of area and temperature (56%)—vascular plants; distance (nearest continent) and vascular plant species richness (75%)—insects; area and chlorophyll concentration (65%)—seabirds; and indigenous insect species richness and age (73%)—land birds. Indigenous insects and plants, along with distance (closest continent), explained most variance (70%) in introduced land bird species richness. A combination of area and temperature explained most variance in species richness of introduced vascular plants (73%), insects (69%), and mammals (69%). However, there was a strong relationship between area and number of human occupants. This suggested that larger islands attract more human occupants, increasing the risk of propagule transfer, while temperature increases the chance of propagule establishment. Consequently, human activities on these islands should be regulated more tightly.
Extracted statement — Investigated species: Insects
Research field: Ecology and Evolutionary Biology
Title: Are competitive effects of native species on an invader mediated by water availability?
Abstract: Question Climate change processes could influence the dynamics of biotic interactions such as plant competition, especially in response to disturbance phenomena such as invasional processes. Are competitive effects of native species on an invader mediated by water availability? Location Glasshouse facility, New South Wales, Australia. Methods We constructed competitive hierarchies for a representative suite of species from coastal dune communities that have been invaded by the Asteraceae shrub, bitou (Chrysanthemoides monilifera subsp. rotundata). We used a comparative phytometer approach, where the invader species was grown with or without a suite of native species in glasshouse trials. This was used to construct competition hierarchies under two water stress conditions: non-droughted and droughted. The treatments were designed to simulate current and potential future water availability respectively. Results We found that the invader experienced fewer competitive effects from some native species under water stress, particularly with regard to below-ground biomass effects. Native species were often poor competitors with the invader, despite their adaptation to periodic water stress in native coastal environments. Of the native species with significant competitive effects on the invader, functionally similar shrub species were the most effective competitors, as expressed in below-ground biomass. The relative position of species in the hierarchy was consistent across water treatments based on below-ground bitou biomass, but was contingent on water treatment when based on above-ground bitou biomass. Conclusions The competitive effects of native species on an invader are affected by water stress. While the direction of response to water stress is species-specific, many species have small competitive effects on the invader under droughted conditions. This could allow an increase in invader dominance with climate change.
Extracted statement — type of experiment: Lab
Research field: Ecology and Evolutionary Biology
Title: An experimental test of Darwin's naturalization hypothesis
Abstract: One of the oldest ideas in invasion biology, known as Darwin’s naturalization hypothesis, suggests that introduced species are more successful in communities in which their close relatives are absent. We conducted the first experimental test of this hypothesis in laboratory bacterial communities varying in phylogenetic relatedness between resident and invading species with and without a protist bacterivore. As predicted, invasion success increased with phylogenetic distance between the invading and the resident bacterial species in both the presence and the absence of protistan bacterivory. The frequency of successful invader establishment was best explained by average phylogenetic distance between the invader and all resident species, possibly indicating limitation by the availability of the unexploited niche (i.e., organic substances in the medium capable of supporting the invader growth); invader abundance was best explained by phylogenetic distance between the invader and its nearest resident relative, possibly indicating limitation by the availability of the unexploited optimal niche (i.e., the subset of organic substances supporting the best invader growth). These results were largely driven by one resident bacterium (a subspecies of Serratia marcescens) posting the strongest resistance to the alien bacterium (another subspecies of S. marcescens). Overall, our findings support phylogenetic relatedness as a useful predictor of species invasion success.
Extracted statement — type of experiment: Lab
Research field: Ecology and Evolutionary Biology
Title: Architectural strategies of Rhamnus cathartica (Rhamnaceae) in relation to canopy openness
Abstract: While phenotypic plasticity is considered the major means that allows plant to cope with environmental heterogeneity, scant information is available on phenotypic plasticity of the whole-plant architecture in relation to ontogenic processes. We performed an architectural analysis to gain an understanding of the structural and ontogenic properties of common buckthorn (Rhamnus cathartica L., Rhamnaceae) growing in the understory and under an open canopy. We found that ontogenic effects on growth need to be calibrated if a full description of phenotypic plasticity is to be obtained. Our analysis pointed to three levels of organization (or nested structural units) in R. cathartica. Their modulation in relation to light conditions leads to the expression of two architectural strategies that involve sets of traits known to confer competitive advantage in their respective environments. In the understory, the plant develops a tree-like form. Its strategy here is based on restricting investment in exploitation str...
Extracted statement — type of experiment: Lab
Research field: Ecology and Evolutionary Biology
Title: Seasonal Photoperiods Alter Developmental Time and Mass of an Invasive Mosquito, Aedes albopictus (Diptera: Culicidae), Across Its North-South Range in the United States
Abstract: ABSTRACT The Asian tiger mosquito, Aedes albopictus (Skuse), is perhaps the most successful invasive mosquito species in contemporary history. In the United States, Ae. albopictus has spread from its introduction point in southern Texas to as far north as New Jersey (i.e., a span of ≈14° latitude). This species experiences seasonal constraints in activity because of cold temperatures in winter in the northern United States, but is active year-round in the south. We performed a laboratory experiment to examine how life-history traits of Ae. albopictus from four populations (New Jersey [39.4° N], Virginia [38.6° N], North Carolina [35.8° N], Florida [27.6° N]) responded to photoperiod conditions that mimic approaching winter in the north (short static daylength, short diminishing daylength) or relatively benign summer conditions in the south (long daylength), at low and high larval densities. Individuals from northern locations were predicted to exhibit reduced development times and to emerge smaller as adults under short daylength, but be larger and take longer to develop under long daylength. Life-history traits of southern populations were predicted to show less plasticity in response to daylength because of low probability of seasonal mortality in those areas. Males and females responded strongly to photoperiod regardless of geographic location, being generally larger but taking longer to develop under the long daylength compared with short day lengths; adults of both sexes were smaller when reared at low larval densities. Adults also differed in mass and development time among locations, although this effect was independent of density and photoperiod in females but interacted with density in males. Differences between male and female mass and development times was greater in the long photoperiod suggesting differences between the sexes in their reaction to different photoperiods. This work suggests that Ae. albopictus exhibits sex-specific phenotypic plasticity in life-history traits matching variation in important environmental variables.
Extracted statement — type of experiment: Lab
Research field: Ecology and Evolutionary Biology
Title: VARIATION IN PHENOTYPIC PLASTICITY AMONG NATIVE AND INVASIVE POPULATIONS OF ALLIARIA PETIOLATA
Abstract: Alliaria petiolata is a Eurasian biennial herb that is invasive in North America and for which phenotypic plasticity has been noted as a potentially important invasive trait. Using four European and four North American populations, we explored variation among populations in the response of a suite of antioxidant, antiherbivore, and morphological traits to the availability of water and nutrients and to jasmonic acid treatment. Multivariate analyses revealed substantial variation among populations in mean levels of these traits and in the response of this suite of traits to environmental variation, especially water availability. Univariate analyses revealed variation in plasticity among populations in the expression of all of the traits measured to at least one of these environmental factors, with the exception of leaf length. There was no evidence for continentally distinct plasticity patterns, but there was ample evidence for variation in phenotypic plasticity among the populations within continents. This implies that A. petiolata has the potential to evolve distinct phenotypic plasticity patterns within populations but that invasive populations are no more plastic than native populations.
Extracted statement — type of experiment: Lab