Search results for " adaptation"
showing 10 items of 504 documents
Helices of disaster memory: How forgetting and remembering influence tropical cyclone response in Mauritius
2020
Abstract Tropical cyclones have had a considerable impact on Mauritius. Large cyclones are relatively rare, and in popular imagination are thought to hit Mauritius every 15 years. Yet it has been over 25 years since the last cyclone widely considered as ‘significant’. Critically, there is little known about the role of memory in responses to cyclones and details regarding responses to past cyclones in Mauritian history are scant. This article examines past experiences and impacts of cyclones in Mauritius, as well as contemporary perceptions of cyclone vulnerability and memories of historical cyclones. The analysis draws on both community interviews and archival research conducted in Mauriti…
Cold adaptation drives population genomic divergence in the ecological specialist, Drosophila montana
2020
Funding: UK Natural Environment Research Council (Grant Number(s): NE/L501852/1, NE/P000592/1); Academy of Finland (GrantNumber(s): 267244, 268214, 322980), Ella ja Georg Ehrnroothin Säätiö. Detecting signatures of ecological adaptation in comparative genomics is challenging, but analysing population samples with characterised geographic distributions, such as clinal variation, can help identify genes showing covariation with important ecological variation. Here, we analysed patterns of geographic variation in the cold-adapted species Drosophila montana across phenotypes, genotypes and environmental conditions and tested for signatures of cold adaptation in population genomic divergence. We…
Evidence of resistance training-induced neural adaptation in older adults
2021
The deleterious effects of aging on force production are observable from the age of 40 upwards, depending on the measure. Neural mechanisms contributing to maximum force production and rate of force development have been suggested as descending drive from supraspinal centers, spinal motoneuron excitability, and corticospinal inhibition of descending drive; all of which influence motor unit recruitment and/or firing rate. Resistance-trained Master athletes offer a good source of information regarding the inevitable effects of aging despite the countermeasure of systematic resistance-training. However, most evidence of neural adaptation is derived from longitudinal intervention studies in pre…
Cytosine methylation patterns suggest a role of methylation in plastic and adaptive responses to temperature in European grayling (Thymallus thymallu…
2020
Temperature is a key environmental parameter affecting both the phenotypes and distributions of organisms, particularly ectotherms. Rapid organismal responses to thermal environmental changes have been described for several ectotherms; however, the underlying molecular mechanisms often remain unclear. Here, we studied whole genome cytosine methylation patterns of European grayling (Thymallus thymallus) embryos from five populations with contemporary adaptations of early life history traits at either 'colder' or 'warmer' spawning grounds. We reared fish embryos in a common garden experiment using two temperatures that resembled the 'colder' and 'warmer' conditions of the natal natural enviro…
The genomic footprint of climate adaptation inChironomus riparius
2017
The gradual heterogeneity of climatic factors produces continuously varying selection pressures across geographic distances that leave signatures of clinal variation in the genome. Separating signatures of clinal adaptation from signatures of other evolutionary forces, such as demographic processes, genetic drift, and adaptation to specific non-clinal conditions of the immediate local environment is a major challenge. Here, we examine climate adaptation in five natural populations of the non-biting midge Chironomus riparius sampled along a climatic gradient across Europe. Our study integrates experimental data, individual genome resequencing, Pool-Seq data, and population genetic modelling.…
Genome-Wide Analysis Reveals Selection Signatures Involved in Meat Traits and Local Adaptation in Semi-Feral Maremmana Cattle
2021
The Maremmana cattle is an ancient Podolian-derived Italian breed raised in semi-wild conditions with distinctive morphological and adaptive traits. The aim of this study was to detect potential selection signatures in Maremmana using medium-density single nucleotide polymorphism array. Putative selection signatures were investigated combining three statistical approaches designed to quantify the excess of haplotype homozygosity either within (integrated haplotype score, iHS) or among pairs of populations (Rsb and XP-EHH), and contrasting the Maremmana with a single reference population composed of a pool of seven Podolian-derived Italian breeds. Overall, the three haplotype-based analyses …
Motor-skill learning in an insect inspired neuro-computational control system
2017
In nature, insects show impressive adaptation and learning capabilities. The proposed computational model takes inspiration from specific structures of the insect brain: after proposing key hypotheses on the direct involvement of the mushroom bodies (MBs) and on their neural organization, we developed a new architecture for motor learning to be applied in insect-like walking robots. The proposed model is a nonlinear control system based on spiking neurons. MBs are modeled as a nonlinear recurrent spiking neural network (SNN) with novel characteristics, able to memorize time evolutions of key parameters of the neural motor controller, so that existing motor primitives can be improved. The ad…
"Islands of divergence" in the Atlantic cod genome represent polymorphic chromosomal rearrangements
2016
- In several species genetic differentiation across environmental gradients or between geographically separate populations has been reported to center at “genomic islands of divergence,” resulting in heterogeneous differentiation patterns across genomes. Here, genomic regions of elevated divergence were observed on three chromosomes of the highly mobile fish Atlantic cod (Gadus morhua) within geographically fine-scaled coastal areas. The “genomic islands” extended at least 5, 9.5, and 13 megabases on linkage groups 2, 7, and 12, respectively, and coincided with large blocks of linkage disequilibrium. For each of these three chromosomes, pairs of segregating, highly divergent alleles were id…
Genomic signatures of local adaptation to the degree of environmental predictability in rotifers
2018
AbstractEnvironmental fluctuations are ubiquitous and thus essential for the study of adaptation. Despite this, genome evolution in response to environmental fluctuations —and more specifically to the degree of environmental predictability– is still unknown. Saline lakes in the Mediterranean region are remarkably diverse in their ecological conditions, which can lead to divergent local adaptation patterns in the inhabiting aquatic organisms. The facultatively sexual rotifer Brachionus plicatilis shows diverging local adaptation in its life-history traits in relation to estimated environmental predictability in its habitats. Here, we used an integrative approach —combining environmental, phe…
Passive exposure to speech sounds induces long-term memory representations in the auditory cortex of adult rats
2016
AbstractExperience-induced changes in the functioning of the auditory cortex are prominent in early life, especially during a critical period. Although auditory perceptual learning takes place automatically during this critical period, it is thought to require active training in later life. Previous studies demonstrated rapid changes in single-cell responses of anesthetized adult animals while exposed to sounds presented in a statistical learning paradigm. However, whether passive exposure to sounds can form long-term memory representations remains to be demonstrated. To investigate this issue, we first exposed adult rats to human speech sounds for 3 consecutive days, 12 h/d. Two groups of …