Search results for " Developmen"

Ants medicate to fight disease

2015

Parasites are ubiquitous, and the ability to defend against these is of paramount importance. One way to fight diseases is self-medication, which occurs when an organism consumes biologically active compounds to clear, inhibit, or alleviate disease symptoms. Here, we show for the first time that ants selectively consume harmful substances (reactive oxygen species, ROS) upon exposure to a fungal pathogen, yet avoid these in the absence of infection. This increased intake of ROS, while harmful to healthy ants, leads to higher survival of exposed ants. The fact that ingestion of this substance carries a fitness cost in the absence of pathogens rules out compensatory diet choice as the mechanis…

Symbiont Genomic Features and Localization in the Bean Beetle Callosobruchus maculatus

2021

A pervasive pest of stored leguminous products, the bean beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae) associates with a simple bacterial community during adulthood. Despite its economic importance, little is known about the compositional stability, heritability, localization, and metabolic potential of the bacterial symbionts of C. maculatus. In this study, we applied community profiling using 16S rRNA gene sequencing to reveal a highly conserved bacterial assembly shared between larvae and adults. Dominated by Firmicutes and Proteobacteria, this community is localized extracellularly along the epithelial lining of the bean beetle's digestive tract. Our analysis revealed that…

2019

Gut bacteria aid their host in digestion and pathogen defense, and bacterial communities that differ in diversity or composition may vary in their ability to do so. Typically, the gut microbiomes of animals living in social groups converge as members share a nest environment and frequently interact. Social insect colonies, however, consist of individuals that differ in age, physiology, and behavior, traits that could affect gut communities or that expose the host to different bacteria, potentially leading to variation in the gut microbiome within colonies. Here we asked whether bacterial communities in the abdomen of Temnothorax nylanderi ants, composed largely of the gut microbiome, differ…

Combining palaeodistribution modelling and phylogeographical approaches for identifying glacial refugia in AlpinePrimula

2013

Aim We investigated the late Quaternary history of two closely related and partly sympatric species of Primula from the south-western European Alps, P. marginata Curtis and P. latifolia Lapeyr., by combining phylogeographical and palaeodistribution modelling approaches. In particular, we were interested in whether the two approaches were congruent and identified the same glacial refugia. Location South-western European Alps. Methods For the phylogeographical analysis we included 352 individuals from 28 populations of P. marginata and 172 individuals from 15 populations of P. latifolia and used amplified fragment length polymorphisms (AFLPs). For palaeodistribution modelling, species distrib…

2019

Abstract The success of social insects is largely intertwined with their highly advanced chemical communication system that facilitates recognition and discrimination of species and nest-mates, recruitment, and division of labor. Hydrocarbons, which cover the cuticle of insects, not only serve as waterproofing agents but also constitute a major component of this communication system. Two cryptic Crematogaster species, which share their nest with Camponotus ants, show striking diversity in their cuticular hydrocarbon (CHC) profile. This mutualistic system therefore offers a great opportunity to study the genetic basis of CHC divergence between sister species. As a basis for further genome-wi…

Potential of a no‐take marine reserve to protect home ranges of anadromous brown trout (Salmo trutta)

2018

The extent to which no-take marine reserves can benefit anadromous species requires examination. Here, we used acoustic telemetry to investigate the spatial behavior of anadromous brown trout (sea trout, Salmo trutta) in relation to a small marine reserve (similar to 1.5 km(2)) located inside a fjord on the Norwegian Skagerrak coast. On average, sea trout spent 42.3 % (+/- 5.0% SE) of their time in the fjord within the reserve, a proportion similar to the area of the reserve relative to that of the fjord. On average, sea trout tagged inside the reserve received the most protection, although the level of protection decreased marginally with increasing home range size. Furthermore, individual…

The enigma of frequency-dependent selection

1997

Frequency-dependent selection is so fundamental to modern evolutionary thinking that everyone interested in evolutionary biology 'knows' the concept. It is even so fundamental that many authors of textbooks do not bother to define it. Yet it turns out that different authors (and sometimes even one and the same author) use the term to refer to different types of selection. In this paper we try to uncover the sources of this confusion. The concept is fairly well defined in the original concept of population genetical theory, which focuses on short-term evolutionary change, and basically ignores density-dependence. The problems start when the original concept is used in the context of long-ter…

Nacre evolution: a proteomic approach.

2009

AbstractFrom an evolutionary viewpoint, the molluscan nacre constitutes a fascinating object. This microstructure appeared early, in the Lower Cambrian period, about 530 million years ago, and since then, has been kept unchanged until today. Nacre is restricted to the conchiferan mollusks, where it occurs in t least three main classes, bivalves, gastropods and cephalopods. The aim of the present study is to investigate whether all nacres are built from the same “macromolecular tools”, proteins of the nacre matrix. To this end, we studied three new nacre models, the freshwater bivalve Unio pictorum, the cephalopod Nautilus macromphalus, and the gastropod Haliotis asinina, to which we applied…

2019

RNA interference (RNAi) is a powerful tool for studying functions of candidate genes in both model and nonmodel organisms and a promising technique for therapeutic applications. Successful application of this technique relies on the accuracy and reliability of methods used to quantify gene knockdown. With the limitation in the availability of antibodies for detecting proteins, quantitative PCR (qPCR) remains the preferred method for quantifying target gene knockdown after dsRNA treatment. We evaluated how qPCR primer binding site and target gene expression levels affect quantification of intact mRNA transcripts following dsRNA-mediated RNAi. The use of primer pairs targeting the mRNA sequen…

Acclimation capacity and rate change through life in the zooplankton Daphnia

2020

When a change in the environment occurs, organisms can maintain an optimal phenotypic state via plastic, reversible changes to their phenotypes. These adjustments, when occurring within a generation, are described as the process of acclimation. While acclimation has been studied for more than half a century, global environmental change has stimulated renewed interest in quantifying variation in the rate and capacity with which this process occurs, particularly among ectothermic organisms. Yet, despite the likely ecological importance of acclimation capacity and rate, how these traits change throughout life among members of the same species is largely unstudied. Here we investigate these re…