Optimal Foraging Theory and the Psychology of Learning

The development of optimization theory has made important contributionsto the study of animal behavior. But the optimization approachneeds to be integrated with other methods of ethology and psychology.For example, the ability to learn is an important componentof efficient foraging behavior in many species, and the psychologyof animal learning could contribute substantially to testingand extending the predictions of optimal foraging theory.     

Inbreeding levels in Northeast Brazil: Strategies for the prospecting of new genetic disorders

A new autosomal recessive genetic condition, the SPOAN syndrome (an acronym for spastic paraplegia, optic atrophy and neuropathy syndrome), was recently discovered in an isolated region of the State of Rio Grande do Norte in Northeast Brazil, in a population that was identified by the IBGE (Brazilian Institute of Geography and Statistics) as belonging to the Brazilian communities with the highest rates of "deficiencies" (Neri, 2003), a term used to describe diseases, malformations, and handicaps in general. This prompted us to conduct a study of consanguinity levels in five of its municipal districts by directly interviewing their inhabitants. Information on 7,639 couples (corresponding to about 40% of the whole population of the studied districts) was obtained. The research disclosed the existence of very high frequencies of consanguineous marriages, which varied from about 9% to 32%, suggesting the presence of a direct association between genetic diseases such as the SPOAN syndrome, genetic drift and inbreeding levels. This fact calls for the introduction of educational programs for the local populations, as well as for further studies aiming to identify and characterize other genetic conditions. Epidemiological strategies developed to collect inbreeding data, with the collaboration of health systems available in the region, might be very successful in the prospecting of genetic disorders.     

Methodological Problems in Evolutionary Biology. XI. Optimal Foraging Theory Revisited

Optimality theory, particularly optimal foraging theory (OFT), has spurned controversy over decades. I argue that the controversy results from conceptual pitfalls. The focus in this article is on pitfalls underlying the concept of constraint. Constraints in OFT models are a means to distinguish between possible and impossible behaviours. I argue that the seemingly innocuous notion of (im)possibility is tricky. It is indeed linked here with troublesome philosophical problems concerning free will. To steer away from such problems in OFT, we need to distinguish between hard and soft constraints. Such a distinction is necessarily context-dependent. This implies that OFT, to a large extent, should take the form of natural history rather than general theory.     

Optimal Foraging Theory: A Review of Some Models and Their Applications

Hunter-Gatherer Foraging Strategies: Ethnographic and Archeological Analyses . Bruce Winterhalter and Eric Alden Smith , eds. Chicago: University of Chicago Press, 1981. x + 268 pp. $18.00 (cloth), $7.50 (paper).     

Optimal Foraging Theory and the Racecar Driver: The Impact of Student-Centered Learning on Anthropological Pedagogy

This article contributes to the field of anthropological pedagogy, adding to recent articles regarding needed change in anthropology teaching methods. All have in common the practice of anthropology in the classroom. The author used the theory of optimal foraging to encourage students to operationalize human behavior. The economic benefit that students reaped warrants discussion. Students rapidly and measurably improved several areas of their lifestyle including health, finance, and home. Pursuing an anthropology degree thus becomes a personal journey.     

Distribution of Chironomidae in a Semiarid Intermittent River of Brazil

The effects of the intermittency of water flow on habitat structure and substrate composition have been reported to create a patch dynamics for the aquatic fauna, mostly for that associated with the substrate. This study aims to describe the spatial distribution of Chironomidae in an intermittent river of semiarid Brazil and to associate assemblage composition with environmental variables. Benthic invertebrates were sampled during the wet and dry seasons using a D-shaped net (40?cm wide and 250???m mesh), and the Chironomidae were identified to genus level. The most abundant genera were Tanytarsus, Polypedilum, and Saetheria with important contributions of the genera Procladius, Aedokritus, and Dicrotendipes. Richness and density were not significantly different between the study sites, and multiple regression showed that the variation in richness and density explained by the environmental variables was significant only for substrate composition. The composition of genera showed significant spatial segregation across the study sites. Canonical Correspondence Analysis showed significant correspondence between Chironomidae composition and the environmental variables, with submerged vegetation, elevation, and leaf litter being important predictors of the Chironomidae fauna. This study showed that Chironomidae presented important spatial variation along the river and that this variation was substantially explained by environmental variables associated with the habitat structure and river hierarchy. We suggest that the observed spatial segregation in the fauna results in the high diversity of this group of organisms in intermittent streams.     

Assessing the Effects of Indigenous Migration on Zootherapeutic Practices in the Semiarid Region of Brazil

Human migration implies adaptations to new environments, such as ways to benefit from the available biodiversity. This study focused on the use of animal-derived remedies, and we investigated the effects of migration on the traditional medical system of the indigenous Truká people. This ethnic group lives in Northeast Brazil and is currently distributed in four distinct villages. In these villages, the zootherapeutic knowledge of 54 indigenous people was determined through semi-structured questionnaires given from September 2013 to January 2014. The interviewees indicated 137 zootherapeutic uses involving 21 animal species. The variety of species and their uses have a higher similarity between villages that are closer to each other, which can be a reflection of geographic and environmental factors. However, even close villages showed a low similarity in the zootherapeutic uses recorded, which reflects a strong idiosyncrasy regarding the knowledge of each village. Hence, each village may be influenced by the physical environment and contact with other cultures, which may maintain or reduce the contact of younger villages with the original village.     

Prediction of Switching and Counter-Switching Based on Optimal Foraging

It is shown that optimally foraging predators can switch or counter-switch depending on prey types and on environmental conditions, due to changes in the profitability of the prey types involved. Subsequently rules are developed to predict switching or counter-switching by the predator when prey densities change, using examples from the literature as well as new data on prey selection in sticklebacks.     

The Optimal Foraging Analysis of Horticultural Production

This paper extends the application of optimal foraging theory to horticultural economies. The Machiguenga, a native Amazonian population of southeastern Peru, are used as a test case. The results demonstrate the theory's utility in structuring questions and predicting the outcome of horticultural production. By extending the range of foraging theory the evolution of subsistence strategies from hunting-gathering to agriculture can be examined in quantitative terms. The evolutionary sequence is illustrated with a hypothetical population. Additional insights are gained when the theory is used to structure specific production decisions. Disagreements concerning the scarcity of protein in Amazonian economies are shown to be a consequence of the measurement units employed.     

Optimal Foraging in Hummingbirds: Testing the Marginal Value Theorem

To a hummingbird, clusters of flowers on inflorescences representpatches and provide an ideal situation to test prediction ofoptimal patch-use. The basic question is what decision ruleshould a hummingbird use to decide whether or not to leave aninflorescence? The hypothesis is that hummingbirds will adoptthe decision rule that maximizes their net rate of energy gainwhile foraging. This hypothesis leads to an analogue of Charnov'smarginal value theorem which determines an optimal decisionrule. The optimal decision ruleis then used to predict aspectsof the hummingbirds' foraging, and these predictions are comparedwith field data The optimal decision rule is a function of how much informationis used by the hummingbirds. Data indicate that a decision toleave an inflorescence is a function of the number of flowersvisited, the number of flowers available on the inflorescence,and the amount of nectar obtained at the last flower. The optimaldecision rule was calculated assuming no additional informationis used.     

Foraging Strategies of Artisanal Fishers in a Brazilian Reservoir

Ecological models derived from Optimal Foraging Theory have been used to understand the decision-making processes and optimization of artisanal fisheries. However, many studies do not consider the influence of fishing techniques or seasonality on foraging strategies. We analyzed the optimization strategies and decision-making processes of the fishers at a Brazilian reservoir. Data were collected through interviews and questionnaires involving 65 artisanal fishers, and daily catches were monitored in July/2015 and January/2016. Fishing techniques and seasonality influenced the fishers’ behavior. The fishery activities monitored here were partially or totally consistent with the predictions of the Central-Place Foraging model, but due to the complexity of these activities, other factors also influenced the decision-making of individual fishers. Furthermore, the adoption of strategies that involve “non-ideal” behaviors may be advantageous for the fishers in the context of their individual necessities.     

Individual Differences in Foraging Strategies of Parasitic Sabre-Tooth Blennies

Originally, evolutionary game theory typically predicted that optimal behaviour in a given situation is uniform or bimodal. However, the growing evidence that animals behave more variably while individuals may differ consistently in their behaviour, has led to the development of models that predict a distribution of strategies. Here we support the importance of such models in a study on a coral reef fish host–parasite system. Parasitic blennies (Plagiotremus sp.) regularly attack other fishes to bite off scales and mucus. Individuals of some victim species react to being bitten with punishing the parasite through aggressive chasing. Our field observations and laboratory experiments show that individual blennies differ markedly in how they incorporate being punished into their foraging decisions. We discuss how these differences may affect the payoff structure and hence the net effect of punishment on punishers and on the appearance of a public good for look-alikes.