725 research outputs found
Welcome to Journal of Ethnobiology and Ethnomedicine
Ethnobiology is a multidisciplinary field of study that draws on approaches and methods from both the social and biological sciences. Ethnobiology aims at investigating culturally based biological and environmental knowledge, cultural perception and cognition of the natural world, and associated behaviours and practices. Ethnomedicine is concerned with the cultural interpretations of health, disease and illness and also addresses the health care seeking process and healing practices. Research interest and activities in the areas of ethnobiology and ethnomedicine have increased tremendously in the last decade. Since the inception of the disciplines, scientific research in ethnobiology and ethnomedicine has made important contributions to understanding traditional subsistence and medical knowledge and practice. The Journal of Ethnobiology and Ethnomedicine (JEE) invites manuscripts and reviews based on original interdisciplinary research from around the world on the inextricable relationships between human cultures and nature, on Traditional Environmental Knowledge (TEK), folk and traditional medical knowledge, as well as on the relevance of the above for Primary Health Care (PHC) policies in developing countries
Detection vs selection: integration of genetic, epigenetic and environmental cues in fluctuating environments
ArticleThere are many inputs during development that influence an organism's fit to current or upcoming environments. These include genetic effects, transgenerational epigenetic influences, environmental cues and developmental noise, which are rarely investigated in the same formal framework. We study an analytically tractable evolutionary model, in which cues are integrated to determine mature phenotypes in fluctuating environments. Environmental cues received during development and by the mother as an adult act as detection-based (individually observed) cues. The mother's phenotype and a quantitative genetic effect act as selection-based cues (they correlate with environmental states after selection). We specify when such cues are complementary and tend to be used together, and when using the most informative cue will predominate. Thus, we extend recent analyses of the evolutionary implications of subsets of these effects by providing a general diagnosis of the conditions under which detection and selection-based influences on development are likely to evolve and coexist.This work was supported by a Leverhulme Trust International Network Grant to the four authors and by a grant from the Swedish Research Council (621-2010-5437) to O.L
«Великий перелом» 1920 – 30-x рр. у контексті регіональної історії
(uk) Розглядається регіональна політика більшовиків щодо селянства у 1920 – 30-х роках, висвітлюється опір селянства насильницькій колективізації в Центральній Україні.(en) The regional policy of bolshevists in relation to peasantry in 1920 – 30 is examined – х years, is lighted resistance of peasantry to violent collectivization in Central Ukraine
Ecological genetic conflict: Genetic architecture can shift the balance between local adaptation and plasticity
This is the author accepted manuscript. The final version is available from University of Chicago Press via the DOI in this record.Genetic polymorphism can contribute to local adaptation in heterogeneous
habitats, for instance as a single locus with alleles adapted to different habitats.
Phenotypic plasticity can also contribute to trait variation across habitats,
through developmental responses to habitat-specific cues. We show that
the genetic architecture of genetically polymorphic and plasticity loci may influence
the balance between local adaptation and phenotypic plasticity. These
effects of genetic architecture are instances of ecological genetic conflict. A
reduced effective migration rate for genes tightly linked to a genetic polymorphism
provides an explanation for the effects, and they can occur both
for a single trait and for a syndrome of co-adapted traits. Using individualbased
simulations and numerical analysis, we investigate how among-habitat
genetic polymorphism and phenotypic plasticity depend on genetic architecture.
We also study the evolution of genetic architecture itself, in the form
of rates of recombination between genetically polymorphic loci and plasticity
loci. Our main result is that for plasticity genes that are unlinked to loci with
between-habitat genetic polymorphism, the slope of a reaction norm is steeper
in comparison with the slope favored by plasticity genes that are tightly linked
to genes for local adaptation.This work was supported by grants from the Carl Trygger
Foundation (CTS 15292) to OL and by a Leverhulme Trust International Network
Grant to SRXD, PH, OL, and JMM
A mechanistic understanding of repellent function against mammalian herbivores
BackgroundBrowsing repellents are widely used to deter large herbivores from consuming plants of ecological, economic and aesthetic importance. Understanding how these repellents function on a behavioural mechanistic level is critical to predicting effectiveness. Here, we illustrate how these mechanisms can be tested, by exposing a model mammalian herbivore, the fallow deer, to different concentrations of a commercial chemical repellent (HaTe2) in two-choice feeding trials.ResultsThe repellent acted as a defensive chemical for the food by both reducing visitation and the amount consumed. Deer favoured the less defended feeders before ingesting any food, suggesting that the repellent altered olfactory and/or visual cues. Deer also consumed less of the more defended food when choosing between low and high repellent feeders than no and low repellent feeders, indicating that the repellent modified flavour and/or sensation. Repellent effectiveness declined with increased exposure, suggesting that consumption had no negative post-ingestive effects, and thus, deterrence was not caused by a conditioned aversion or irritation. Instead, this pattern suggests that deer learned, through repeated sampling of repellent-treated food, that there was no adverse physiological effect of ingesting it.ConclusionsThese results imply that HaTe2 repellent will not be effective over prolonged periods or in the absence of alternative untreated food. Understanding the mechanisms driving repellent function using two-choice trials could help practitioners decide whether a particular repellent is likely to be effective against mammalian herbivory in their management scenario
Joint evolution of multiple social traits: a kin selection analysis
General models of the evolution of cooperation, altruism and other social behaviours have focused almost entirely on single traits, whereas it is clear that social traits commonly interact. We develop a general kin-selection framework for the evolution of social behaviours in multiple dimensions. We show that whenever there are interactions among social traits new behaviours can emerge that are not predicted by one-dimensional analyses. For example, a prohibitively costly cooperative trait can ultimately be favoured owing to initial evolution in other (cheaper) social traits that in turn change the cost-benefit ratio of the original trait. To understand these behaviours, we use a two-dimensional stability criterion that can be viewed as an extension of Hamilton's rule. Our principal example is the social dilemma posed by, first, the construction and, second, the exploitation of a shared public good. We find that, contrary to the separate one-dimensional analyses, evolutionary feedback between the two traits can cause an increase in the equilibrium level of selfish exploitation with increasing relatedness, while both social (production plus exploitation) and asocial (neither) strategies can be locally stable. Our results demonstrate the importance of emergent stability properties of multidimensional social dilemmas, as one-dimensional stability in all component dimensions can conceal multidimensional instability
Learning leads to bounded rationality and the evolution of cognitive bias in public goods games
Efficient application of a browsing repellent: Can associational effects within and between plants be exploited?
publishedVersio
Upstream reciprocity in heterogeneous networks
Many mechanisms for the emergence and maintenance of altruistic behavior in
social dilemma situations have been proposed. Indirect reciprocity is one such
mechanism, where other-regarding actions of a player are eventually rewarded by
other players with whom the original player has not interacted. The upstream
reciprocity (also called generalized indirect reciprocity) is a type of
indirect reciprocity and represents the concept that those helped by somebody
will help other unspecified players. In spite of the evidence for the
enhancement of helping behavior by upstream reciprocity in rats and humans,
theoretical support for this mechanism is not strong. In the present study, we
numerically investigate upstream reciprocity in heterogeneous contact networks,
in which the players generally have different number of neighbors. We show that
heterogeneous networks considerably enhance cooperation in a game of upstream
reciprocity. In heterogeneous networks, the most generous strategy, by which a
player helps a neighbor on being helped and in addition initiates helping
behavior, first occupies hubs in a network and then disseminates to other
players. The scenario to achieve enhanced altruism resembles that seen in the
case of the Prisoner's Dilemma game in heterogeneous networks.Comment: 10 figures, Journal of Theoretical Biology, in press (2010
Evolutionarily stable defence and signalling of that defence
We examine the evolution and maintenance of defence and conspicuousness in prey species using a game theoretic model. In contrast to previous works, predators can raise as well as lower their attack probabilities as a consequence of encountering moderately defended prey. Our model predicts four distinct possibilities for evolutionarily stable strategies (ESSs) featuring maximum crypsis. Namely that such a solution can exist with (1) zero toxicity, (2) a non-zero but non-aversive level of toxicity, (3) a high, aversive level of toxicity or (4) that no such maximally cryptic solution exists. Maximally cryptic prey may still invest in toxins, because of the increased chance of surviving an attack (should they be discovered) that comes from having toxins. The toxin load of maximally cryptic prey may be sufficiently strong that the predators will find them aversive, and seek to avoid similar looking prey in future. However, this aversiveness does not always necessarily trigger aposematic signalling, and highly toxic prey can still be maximally cryptic, because the increased initial rate of attack from becoming more conspicuous is not necessarily always compensated for by increased avoidance of aversive prey by predators. In other circumstances, the optimal toxin load may be insufficient to generate aversion but still be non-zero (because it increases survival), and in yet other circumstances, it is optimal to make no investment in toxins at all. The model also predicts ESSs where the prey are highly defended and aversive and where this defence is advertised at a cost of increased conspicuousness to predators. In many circumstances there is an infinite array of these aposematic ESSs, where the precise appearance is unimportant as long as it is highly visible and shared by all members of the population. Yet another class of solutions is possible where there is strong between-individual variation in appearance between conspicuous, poorly defended prey
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