Search results for "PET"

Effects of root hemiparasitic infection on host performance: Reduced flower size and increased flower asymmetry

2001

We conducted two pot experiments to examine the relationship between hemiparasitic plant (Rhinanthus serotinus, Scrophulariaceae) infection and host (Linum usitatissimum, Linaceae and Brassica rapa ssp. oleifera, Brassicaceae) performance. We were especially interested in the effects of hemiparasitism on the size and shape asymmetry of host flowers, since neither subject has been studied before. We also conducted a field experiment to examine the effects of shape asymmetry of B. rapa ssp. oleifera flowers on pollination success. The shape of flowers produced by both L. usitatissimum and B. rapa ssp. oleifera plants grown without parasites was less asymmetric, and for both host species, the …

Comment on the letter of the Society of Vertebrate Paleontology (SVP) dated April 21, 2020 regarding “Fossils from conflict zones and reproducibility…

2020

International audience

Toxicity and Binding Studies of Bacillus thuringiensis Cry1Ac, Cry1F, Cry1C, and Cry2A Proteins in the Soybean Pests Anticarsia gemmatalis and Chryso…

2017

ABSTRACT Anticarsia gemmatalis (velvetbean caterpillar) and Chrysodeixis includens (soybean looper, formerly named Pseudoplusia includens ) are two important defoliating insects of soybeans. Both lepidopteran pests are controlled mainly with synthetic insecticides. Alternative control strategies, such as biopesticides based on the Bacillus thuringiensis (Bt) toxins or transgenic plants expressing Bt toxins, can be used and are increasingly being adopted. Studies on the insect susceptibilities and modes of action of the different Bt toxins are crucial to determine management strategies to control the pests and to delay outbreaks of insect resistance. In the present study, the susceptibilitie…

Behavioural, ecological, and evolutionary aspects of diversity in frog colour patterns

2016

The role of colours and colour patterns in behavioural ecology has been extensively studied in a variety of contexts and taxa, while almost overlooked in many others. For decades anurans have been the focus of research on acoustic signalling due to the prominence of vocalisations in their communication. Much less attention has been paid to the enormous diversity of colours, colour patterns, and other types of putative visual signals exhibited by frogs. With the exception of some anecdotal observations and studies, the link between colour patterns and the behavioural and evolutionary ecology of anurans had not been addressed until approximately two decades ago. Since then, there has been eve…

Variation in the immune state of Gammarus pulex (Crustacea, Amphipoda) according to temperature: are extreme temperatures a stress?

2017

9 pages; International audience; Temperature is known to impact host-parasite interactions in various ways. Such effects are often regarded as the consequence of the increased metabolism of parasites with increasing temperature. However, the effect of temperature on hosts' immune system could also be a determinant. Here we assessed the influence of temperature on the immunocompetence of the crustacean amphipod Gammarus pulex. Amphipods play a key ecological role in freshwater ecosystems that can be altered by several parasites. We investigated the consequences of three weeks of acclimatization at four temperatures (from 9 °C to 17 °C) on different immunological parameters. Temperature influ…

Multiple mechanisms of cryptic female choice act on intraspecific male variation in Drosophila simulans

2016

Postcopulatory sexual selection can arise when females mate with multiple males and is usually mediated by an interaction between the sexes. Cryptic female choice (CFC) is one form of postcopulatory sexual selection that occurs when female morphology, physiology, or behavior generates a bias in fertilization success. However, its importance in nonrandom reproductive success is poorly resolved due to challenges distinguishing the roles of females and males in generating patterns of fertilization bias. Nevertheless, two CFC mechanisms have recently been documented and characterized in Drosophila simulans within the context of gametic isolation in competitive hybrid matings with Drosophila mau…

Marine protected areas rescue a sexually selected trait in European lobster

2020

Abstract Marine protected areas (MPAs) are increasingly implemented worldwide to maintain and restore depleted populations. However, despite our knowledge on the myriad of positive responses to protection, there are few empirical studies on the ability to conserve species’ mating patterns and secondary sexual traits. In male European lobsters (Homarus gammarus), the size of claws relative to body size correlates positively with male mating success and is presumably under sexual selection. At the same time, an intensive trap fishery exerts selection against large claws in males. MPAs could therefore be expected to resolve these conflicting selective pressures and preserve males with large cl…

Reproductive interference in insects

2017

Reproductive inequalities in the acanthocephalan Corynosoma cetaceum: looking beyond 'crowding' effects.

2018

Background: At present, much research effort has been devoted to investigate overall (average) responses of parasite populations to specific factors, e.g., density-dependence in fecundity or mortality. However, studies on parasite populations usually pay little attention to individual variation (inequality) in reproductive success. A previous study on the acanthocephalan Corynosoma cetaceum in franciscana dolphins, Pontoporia blainvillei, revealed no overall intensity-dependent, or microhabitat effects, on mass and fecundity of worms. In this study, we investigated whether the same factors could influence mass inequalities for this species of acanthocephalan.Methods: A total of 10,138 speci…

New national and regional bryophyte records, 48

2016

Andreaea rothii has been recorded for the first time in Croatia. It is a boreo-temperate suboceanic species (Hill et al., 2007) relatively rare in SE Europe, since it is known only from Romania (Ellis et al., 2014d), Slovenia and Serbia (Sabovljevic´ et al., 2008 ; Hodgetts, 2015). The species was found in the Papuk Mountains, situated in the mainly lowland area of NE Croatia. In this region Papuk is the largest and highest mountain range, with peaks between 800 and 900 m a.s.l. They are characterized by high geological diversity dominated by metamorphic rocks, such as different types of schists, as well as granites. The climate is temperate, moderately warm without an explicit dry period. …