Search results for "ADO"
showing 10 items of 13500 documents
Evidence for ontogenetically and morphologically distinct alternative reproductive tactics in the invasive Round Goby Neogobius melanostomus.
2017
Alternative reproductive tactics are characterized by the occurrence of discrete alternative morphs that differ in behavioural, morphological and physiological traits within the same sex. Although much effort has been made to describe the behaviour, morphology and physiology of such alternative morphs, less effort has been invested investigating how much overlap there is in the characteristics of such morphs in natural populations. We studied random population samples of the invasive Round Goby Neogobius melanostomus from five different localities in the river Rhine system in the Netherlands. We found two morphologically and physiologically distinct male morphs which likely represent altern…
Cyclical and stochastic thermal variability affects survival and growth in brook trout
2019
Directional changes in temperature have well-documented effects on ectotherms, yet few studies have explored how increased thermal variability (a concomitant of climate change) might affect individual fitness. Using a common-garden experimental protocol, we investigated how bidirectional temperature change can affect survival and growth of brook trout (Salvelinus fontinalis) and whether the survival and growth responses differ between two populations, using four thermal-variability treatments (mean: 10 °C; range: 7–13 °C): (i) constancy; (ii) cyclical fluctuations every two days; (iii) low stochasticity (random changes every 2 days); (iv) high stochasticity (random changes daily). Recently …
Prolonged diapause has sex-specific fertility and fitness costs
2019
AbstractDiapause in seasonal environments allows insects to survive adverse seasons. However, individuals can sometimes enter a prolonged diapause for more than a year, and also skip favourable seasons, which can bring additional costs through e.g. loss of metabolic resources. At the same time, prolonged diapause can be beneficial if it allows individuals to have a risk-spreading strategy to skip potentially suboptimal breeding seasons. We studied if prolonged diapause (2-year diapause) negatively affects the fertility and fitness of female and male Colorado potato beetles (Leptinotarsa decemlineata) compared to control (1-year diapause) beetles. We also tested the parental effects on the s…
Are there autochthonous Ferrissia (Mollusca: Planorbidae) in the Palaearctic? Molecular evidence of a widespread North American invasion of the Old W…
2017
In the last few decades, findings of freshwater limpets belonging to the genus Ferrissia have been frequent and widely distributed throughout the Palaearctic and beyond. The widespread presence of a Nearctic alien taxon was proved, but no consensus was achieved about the possible existence of autochthonous Ferrissia taxa in the area, an occurrence which would be supported by the presence of gastropod fossils attributed to the genus throughout Eurasia and North Africa. In order to test the hypothesis of a possible persistence of autochthonous Ferrissia taxa in the Palaearctic to the present day, all the published data on the genetic diversity of Ferrissia populations occurring in the area we…
Interactions between dark septate endophytes, ectomycorrhizal fungi and root pathogens in vitro
2019
ABSTRACT Dark septate endophytes (DSEs) are widely distributed worldwide and can promote plant growth. Therefore, they are considered potentially important plant allies, especially in stressful environments. Previous studies have reported that DSEs cohabit roots with other microorganisms such as ectomycorrhizal (ECM), endophytic and pathogenic fungi/oomycetes. However, interactions between different DSE species have not yet been reported, and studies on the interactions between DSEs and other fungi are scarce. Using a simple and reproducible pairwise growth assay in vitro, we studied the synergistic/antagonistic interactions between eight DSEs, two ECM fungi and three root pathogens. Most o…
Pilosella hoppeana subsp. sicula Di Grist., Gottschl. & Raimondo (Asteraceae), a new endemic subspecies from Sicily (Italy)
2016
Abstract Di Gristina, E., G. Gottschlich & F.M. Raimondo (2016). Pilosella hoppeana subsp. sicula Di Grist., Gottschl. & Raimondo (Asteraceae), a new endemic subspecies from Sicily (Italy). Candollea 71: 7–12. In English, English abstract. DOI : http://dx.doi.org/10.15553/c2016v711a2 Pilosella hoppeana subsp. sicula Di Grist., Gottschl. & Raimondo (Asteraceae), a new endemic subspecies from the Madonie and Nebrodi Mountains (Sicily, Italy), is described and illustrated. It is morphologically close to Pilosella hoppeana subsp. macrantha (Ten.) S. Braut. & Greuter, but the two subspecies can be distinguished by the indument on the bracts. Its morphology, distribution, ecology, taxonomic relat…
Unexpected increases in rotifer resting egg abundances during the period of contamination of Lake Orta
2016
<p>Despite their ecological importance and rapid response to environmental changes, rotifers are rarely included in palaeolimnological studies. Here, we describe changes in abundance (ABD) and morphotype (MTs) diversity of rotifer resting eggs in the sediments of deep subalpine Lake Orta, Italy, covering a period prior to (pre-) 1926, during long-term ammonia and metal pollution from a rayon factory, and subsequent recovery of water quality. Following the pollution and bacterial oxidation of the ammonia, Lake Orta became the largest and deepest acid lake in Europe. Recovery of water quality followed both a ban on the discharge of industrial wastes, and a liming intervention in 1989 an…
Is a change in juvenile hormone sensitivity involved in range expansion in an invasive beetle?
2015
Introduction: It has been suggested that rapid range expansion could proceed through evolution in the endocrinological machinery controlling life-history switches. Based on this we tested whether the Colorado potato beetle, Leptinotarsa decemlineata, which has rapidly expanded its range across latitudinal regions in Europe, and shows photoperiodic adaptation in overwintering initiation, has different sensitivities to juvenile hormone (JH) manipulation along a latitudinal gradient. Results: A factorial experiment where beetles were reared either under a long or short day photoperiod was performed. Hormone levels were manipulated by topical applications. An allatostatin mimic, H17, was used t…
Cold water reduces the severity of parasite-inflicted damage : support for wintertime recuperation in aquatic hosts
2019
The reduction in host fitness caused by parasite infections (virulence) depends on infection intensity and the degree of damage caused per parasite. Environmental conditions can shape both virulence components, but in contrast to infection intensity, environmental impacts on per-parasite damage are poorly understood. Here, we studied the effect of ambient temperature on per-parasite damage, which is jointly determined by the ability of parasites to induce harm (per-parasite pathogenicity) and the ability of hosts to limit damage (tolerance). We experimentally exposed two salmonid species, Atlantic salmon (Salmo salar) and sea trout (Salmo trutta), to replicated genotypes of the eye fluke Di…
Can green infrastructure help to conserve biodiversity?
2017
The gradually decreasing connectivity of habitats threatens biodiversity and ecological processes valuable to humans. Green infrastructure is promoted by the European Commission as a key instrument for the conservation of ecosystems in the EU biodiversity strategy to 2020. Green infrastructure has been defined as a network of natural and semi-natural areas, designed and managed to deliver a wide range of ecosystem services. We surveyed Finnish experts' perceptions on the development of green infrastructure within the existing policy framework. Our results show that improving the implementation of existing conservation policy instruments needs to be an integral part of developing green infr…