Search results for "Systematic"
showing 10 items of 7608 documents
The long journey of Orthotrichum shevockii (Orthotrichaceae, Bryopsida): From California to Macaronesia
2019
Biogeography, systematics and taxonomy are complementary scientific disciplines. To understand a species' origin, migration routes, distribution and evolutionary history, it is first necessary to establish its taxonomic boundaries. Here, we use an integrative approach that takes advantage of complementary disciplines to resolve an intriguing scientific question. Populations of an unknown moss found in the Canary Islands (Tenerife Island) resembled two different Californian endemic species: Orthotrichum shevockii and O. kellmanii. To determine whether this moss belongs to either of these species and, if so, to explain its presence on this distant oceanic island, we combined the evaluation of…
Training experiments with Bombus terrestris and Apis mellifera on artificial ‘ Salvia ’ flowers
2016
Abstract Many bee flowers demand physical force from their pollinators. An example is Salvia with lever-like anthers restricting access to nectar. Though the needed force is generally low, it is largely unknown how far even low forces affect flower preference and foraging behaviour of bees. In the present paper, we introduce a method to measure the response of bees to a force mechanism. We explain the construction of artificial flowers mimicking the lever mechanism of a Salvia flower and the procedure to train honeybees and bumblebees to the models. We document the behaviour of the bees on models without barriers and on those with low forces aiming at the same time to determine the bees’ se…
Preparing a revision of the International Code of Nomenclature of Prokaryotes
2020
The Editorial Board of the International Code of Nomenclature of Prokaryotes here explains the proposed procedure towards the production of the next revision of the Prokaryotic Code, to include public discussion of a draft version, to be prepared by the editors, followed by balloting of the members of the International Committee on Systematics of Prokaryotes.
Líquenes y hongos liquenícolas de la Serranía de Ronda (Málaga-Cádiz), sur de España
2017
As a result of a field trip organised by the Spanish Lichen Society in Serranía de Ronda, south Spain, a catalogue of 360 taxa is presented (336 lichens, 24 lichenicolous fungi). The list includes three new records for the Iberian Peninsula: Arthonia paretinaria, Micarea myriocarpa and Niesslia keissleri, 51new ones for the Autonomous Andalusian Community, and three and 81 new ones for the province of Cádiz and of Málaga, respectively. After these results, the total updated number of the province of Málaga rises to 556 lichens and lichenicolous fungi. The best represented lichen genus is Cladonia (18) with the most species, unlike Lecanora (15), Pertusaria (12), Physconia (12) and Collema (…
The macroecology of chemical communication in lizards: do climatic factors drive the evolution of signalling glands?
2018
Chemical communication plays a pivotal role in shaping sexual and ecological interactions among animals. In lizards, fundamental mechanisms of sexual selection such as female mate choice have rarely been shown to be influenced by quantitative phenotypic traits (e.g., ornaments), while chemical signals have been found to potentially influence multiple forms of sexual and social interactions, including mate choice and territoriality. Chemical signals in lizards are secreted by glands primarily located on the edge of the cloacae (precloacal glands, PG) and thighs (femoral glands), and whose interspecific and interclade number ranges from 0 to > 100. However, elucidating the factors underlying …
Predator-induced Contemporary Evolution, Phenotypic Plasticity, and the Evolution of Reaction Norms in Guppies
2017
An increasingly large number of studies have demonstrated the ability of populations to undergo contemporary or rapid evolution. Little explored in this regard is the role of phenotypic plasticity, although it can influence eco-evolutionary dynamics and hence evolutionary rates. Here we quantify the evolution of life history and plasticity in Trinidadian guppies transplanted from high to novel low predation environments. Common-garden results show that after only nine years, or 13–27 generations, the introduced guppies have diverged from their ancestral population in both litter size and offspring weight and in the plastic response of both traits to food availability. Given these findings, …
Sexual selection and the chemical signal design of lacertid lizards
2018
Animal signals can differ considerably in complexity and composition, even among closely related species. Work on vocal and visual signals has revealed how sexual selection can elaborate signals relevant in mate choice or rival assessment, but few studies have investigated this process in chemical signals. In this study, we correlated chemical signalling diversity and richness with degree of sexual dimorphism in a data set of 60 species of the lizard family Lacertidae. The femoral glands of male lacertid lizards exude waxy secretions, of which the lipophilic fraction is known to function in chemical communication. We determined the composition of the gland secretions using gas chromatograph…
Expression of miR159 Is Altered in Tomato Plants Undergoing Drought Stress.
2019
In a scenario of global climate change, water scarcity is a major threat for agriculture, severely limiting crop yields. Therefore, alternatives are urgently needed for improving plant adaptation to drought stress. Among them, gene expression reprogramming by microRNAs (miRNAs) might offer a biotechnologically sound strategy. Drought-responsive miRNAs have been reported in many plant species, and some of them are known to participate in complex regulatory networks via their regulation of transcription factors involved in water stress signaling. We explored the role of miR159 in the response of Solanum lycopersicum Mill. plants to drought stress by analyzing the expression of sly-miR159 and …
Biased predation could promote convergence yet maintain diversity within Müllerian mimicry rings of Oreina leaf beetles.
2019
Mullerian mimicry is a classic example of adaptation, yet Muller's original theory does not account for the diversity often observed in mimicry rings. Here, we aimed to assess how well classical Mullerian mimicry can account for the colour polymorphism found in chemically defended Oreina leaf beetles by using field data and laboratory assays of predator behaviour. We also evaluated the hypothesis that thermoregulation can explain diversity between Oreina mimicry rings. We found that frequencies of each colour morph were positively correlated among species, a critical prediction of Mullerian mimicry. Predators learned to associate colour with chemical defences. Learned avoidance of the green…
Social transmission of avoidance among predators facilitates the spread of novel prey.
2018
Warning signals are an effective defence strategy for aposematic prey, but only if they are recognized by potential predators. If predators must eat prey to associate novel warning signals with unpalatability, how can aposematic prey ever evolve? Using experiments with great tits (Parus major) as predators, we show that social transmission enhances the acquisition of avoidance by a predator population. Observing another predator’s disgust towards tasting one novel conspicuous prey item led to fewer aposematic than cryptic prey being eaten for the predator population to learn. Despite reduced personal encounters with unpalatable prey, avoidance persisted and increased over subsequent trials.…