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Diversity of Idea Flows and Economic Growth

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Journal of Social Computing 2020年第1期1卷 71-81页

作者： Alex Pentland Institute of Technology(MIT) CambridgeMA 02139-4307USA

What role does access to diverse ideas play in economic growth?New forms of geo-located communications and economic data allow measurement of human interaction patterns and prediction of economic outcomes for individuals,communities,and nations at a fine granularity,with the strongest predictors of income,productivity,and growth being measures of diversity and frequency of physical interaction between communities(clusters of interaction).This finding provides both new investment opportunities and new methods of risk *** and use of these data raise privacy and security risks,and the final section of the paper describes how these challenges can be controlled.

关键词： idea flow opportunity wealth inequality segregation foraging privacy policy

Sex,size,and prey caloric value affect diet specialization and consumption of an invasive prey by a native predator

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Current Zoology 2019年第5期65卷 499-507页

作者： Lauren E.HOSTERT Lauren M.PINTOR James E.BYERS School of Environment and Natural Resources The Ohio State UniversityColumbusOHUSA Odum School of Ecology University of GeorgiaAthensGAUSA

Escaping the control of natural enemies is thought to heavily influence the establishment success and impact of non-native ***,we examined how the profitability of alternative prey in combination with the presence of a competitor and predator aggressive behavior explain individual differences in diet specialization and the consumption of the invasive green porcelain crab Petrolisthes armatus by the native mud crab predator Panopeus *** from bomb calorimetry estimates show that invasive *** has high caloric value relative to alternative native *** assays indicated that specialization and consumption of invasive *** was mostly exhibited by large,female ***,but the presence of a competitor and predator aggressiveness did not influence diet and the consumption of ***,intrinsic factors(e.g.,sex and body size)seem to explain consumption of *** ar\6 dietary specialization in ***,more *** there are still many predator individuals that do not consume ***,the proportion of individuals that have begun to specialize on *** suggests that for some,it has become more profitable relative to alternative native *** the high caloric value of ***,we suggest that it is likely that differences in the cost of its consumption,including attack,capture,and handling times relative to alternative prey,determine its net profitability to individual predators.

关键词： diet breadth optimal foraging theory enemy escape hypothesis competition aggressive behavior

A Novel Improved Bird Swarm Algorithm for Solving Bound Constrained Optimization Problems

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Wuhan University Journal of Natural Sciences 2019年第4期24卷 349-359页

作者： WANG Yuhe WAN Zhongping PENG Zhenhua School of Mathematics and Statistics Wuhan University

Bird swarm algorithm(BSA), a novel bio-inspired algorithm, has good performance in solving numerical optimization problems. In this paper, a new improved bird swarm algorithm is conducted to solve unconstrained optimization problems. To enhance the performance of BSA, handling boundary constraints are applied to fix the candidate solutions that are out of boundary or on the boundary in iterations, which can boost the diversity of the swarm to avoid the premature problem. On the other hand, we accelerate the foraging behavior by adjusting the cognitive and social components the sin cosine coefficients. Simulation results and comparison based on sixty benchmark functions demonstrate that the improved BSA has superior performance over the BSA in terms of almost all functions.

关键词： improved bird swarm algorithm handling boundary constraints foraging behavior heuristic algorithm

comCharacteristics of browsed aspen forests following wildfire and implications for management:a case study

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Journal of Plant Ecology 2017年第6期10卷 949-957页

作者： James R.Biggs Dawn M.VanLeeuwen Jerry L.Holechek Sherri L.Sherwood Raul Valdez Forestry Program Natural Resources Management DepartmentNew Mexico Highlands UniversityLas VegasNew Mexico 87701USA Agricultural Biometric Service New Mexico State UniversityLas CrucesNew Mexico 88003USA Department Animal and Range Sciences New Mexico State UniversityLas CrucesNew Mexico 88003USA Los Alamos National Laboratory Los AlamosNew Mexico 87545USA Department Fishery and Wildlife Sciences New Mexico State UniversityLas CrucesNew Mexico 88003USA

Aims Recognizing ungulate browsing thresholds between viable and declining aspen(Populus tremuloides Michx.)stands are critical to ensuring long-term persistence of this biologically important plant *** have shown declines in vigor and regeneration when as few as 30%of current annual twigs are browsed while other studies have shown higher *** the effects of ungulate herbivory are of concern in aspen forests,few studies have assessed browsing effects following wildfire and few criteria exist for deter-mining potential effects of ungulate browsing on aspen forests fol-lowing *** evaluated the effects of ungulate abundance and foraging intensity on regenerating aspen 1 to 6 years post-fire and assessed the use of abundance and foraging intensity indicators in predicting impacts to regenerating *** Mountain elk(Cervus elaphus nelson)was the primary ungulate in the study *** The study area was located within the 17500 ha cerro Grande Fire burn area in the Jemez Mountains,New Mexico,*** used percent aspen twigs browsed and pellet-group counts to evaluate relationships between these indicators and aspen patch structure(height,size).We collected data in randomly generated 3×33 m plots 5-6 years *** also established 4 fenced exclosures(25×55 m and 3.3 m in height)with paired unfenced plots 1-year post-fire to monitor aspen *** spring,we recorded percent browsed twigs from the previous fall through the early spring period which coincided with the highest ungulate use period within the study *** assessed associations between percent twigs browsed and pellet-group density and patch size and height of aspen using Spearman’s correlation *** Findings Mean percent twigs browsed and ungulate pellet-group density across the burn area was≤31%and 1 pellet-group 100 sq m−1,*** size and height decreased with increasing browsing and pellet-group density 5-6 years ***

关键词： ungulate regeneration transitory range pellet-group foraging

Age and ovarian development are related to worker personality and task allocation in the ant Leptothorax acervorum

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Current Zoology 2014年第3期60卷 392-400页

作者： Stephan KIOHBANDNER Andreas P. MODLMEIER Susanne FOITZIK Institute of Zoology University of Regensburg Regensburg Germany Department Biology II Ludwig Maximilian University Munich Planegg-Martinsried Germany Institute of Zoology Johannes Gutenberg University Mainz Germany Department of Biological Sciences University of Pittsburgh Pittsburgh PA 15260 U.S.A.

In social insects, workers of different morphological castes and age are known to act differently. Yet, it is unclear how body size and ovarian development influence worker personalities （i.e. consistent behavioral variation） and task allocation in similar aged ant workers of monomorphic species. Behavioral variation is thought to be a key element of division of labor, but few studies have linked worker personality to task allocation. We investigated individual behavior in Leptothorax acervorum ant workers at two time points during the first three months of their life and in two different settings. We observed worker behavior in the nest （i.e. task allocation） and in standardized aggression, exploration and brood care experiments （i.e. personality） and found behavioral repeatability in foraging and exploration. Further, workers acted consistently across settings： workers with a more ag gressive and exploratory personality type were more active in the nest. Moreover, ovarian development was associated with worker personality and task allocation： older workers with welldeveloped ovaries foraged less, but were more aggressive and exploratory. In accordance with the typical agepolyethism of social insects, workers became more active and foraged more as they grew older. Consequently, our study suggests that task allocation in Leptothorax acervorum is not only influenced by ovari an development and age, but moreover by the personalities of its workers .

关键词： Personality Behavioral syndrome Division of labor Ovarian development foraging Social insects

Cross inhibition improves activity selection when switching incurs time costs

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Current Zoology 2015年第2期61卷 242-250页

作者： James A. R. MARSHALL Angelique FAVR EAU-PEIGN Lutz FROMHAGE John M. MCNAMARA Liarme F. S. MEAH Alasdair I. HOUSTON Department of Computer Science and University of Sheffield Sheffield S 1 4DP UK INRA UMR791 Modelisation Systemique Appliquee aux Ruminants F-75005 Paris France Department of Biological and Environmental Science P.O. Box 35 FI-40014 University of Jyvaskyla Finland School of Mathematics University of Bristol University Walk Bristol BS8 1TW UK School of Biological Sciences University of Bristol Bristol Life Sciences Building 24 Tyndall Avenue Bristol BS8 1TQ UK AgroParisTech UMR Modelisation Systemique Appliquee anx Ruminants F-75005 Paris France

We consider a behavioural model of an animal choosing between two activities, based on positive feedback, and exa- mine the effect of introducing cross inhibition between the motivations for the two activities. While cross-inhibition has pre- viously been included in models of decision making, the question of what benefit it may provide to an animal＇s activity selection behaviour has not previously been studied. In neuroscience and in collective behaviour cross-inhibition, and other equivalent means of coupling evidence-accumulating pathways, have been shown to approximate statistically-optimal decision-making and to adaptively break deadlock, thereby improving decision performance. Switching between activities is an ongoing decision process yet here we also find that cross-inhibition robustly improves its efficiency, by reducing the frequency of costly switches between behaviours .

关键词： Crossinhibition Geometric framework foraging Activity selection Neuroscience Behaviour

Foot strike patterns and hind limb joint angles during running in Hadza hunter-gatherers

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Journal of Sport and Health Science 2014年第2期3卷 95-101,153+156页

作者： Herman Pontzer Kelly Suchman David A.Raichlen Brian M.Wood Audax Z.P.Mabulla Frank W.Marlowe Department of Anthropology Hunter College City University of New York New York Consortium for Evolutionary Primatology Evolutionary Anthropology Duke University School of Anthropology University of Arizona Department of Anthropology Yale University Department of Archeology University of Dar es Salaam Department of Archaeology and Anthropology University of Cambridge

Background:Investigations of running gait among barefoot and populations have revealed a diversity of foot strike behaviors,with some preferentially employing a rearfoot strike(RFS) as the foot touches down while others employ a midfoot strike(MFS) or forefoot strike(FFS).Here,we report foot strike behavior and joint angles among traditional Hadza hunter-gatherers living in Northern ***:Hadza adults(n = 26) and juveniles(n = 14) ran at a range of speeds(adults:mean 3.4 ± 0.7 m/s,juveniles:mean 3.2 ± 0.5 m/s) over an outdoor trackway while being recorded via high-speed digital *** strike type(*** FFS) and hind limb segment angles at foot strike were ***:Hadza men preferentially employed MFS(86.7%of men),while Hadza women and juveniles preferentially employed RFS(90.9%and85.7%of women and juveniles,respectively).No FFS was ***,the presence of footwear(sandals ***),and trial duration had no effect on foot strike ***:Unlike other habitually barefoot populations which prefer FFS while *** men preferred *** Hadza women and juveniles preferred *** and age differences in foot strike behavior among Hadza adults may reflect differences in running experience,with men learning to prefer MFS as they accumulate more running experience.

关键词： Barefoot Biomechanics Foot strike foraging Running

Life Stage, Gender and Movement of Blue Crabs (Callinectes sapidus) in Lake Mattamuskeet and Connecting Canals

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Journal of Fisheries Science 2019年第2期1卷 7-19页

作者： Julia Chen Rinaldi James Hench M.Zachary Darnell Matthew Kukurugya Daniel Rittschof Stantec 265 Clinton StBrooklynNY11201202-494-4462United States 135 Duke Marine Lab Road MSC Nicholas SchoolDuke University BeaufortNC 2851650-759-6639United States Gulf Coast Research Lab 703 E.Beach Dr.Ocean SpringsMS 39564Division of Coastal SciencesSchool of Ocean Science and EngineeringThe University of Southern Mississippi228-872-4298United States Molecular and Cell Biology UC Berkley 635 Tennessee St.San FranciscoCA 94107219-793-4375United States MSC Nicholas SchoolDuke University135 Duke Marine Lab RoadBeaufortNC 28516252-504-7634United States

In their ranges on east and south coasts of the Americas as well as their established invasions in the Adriatic and Baltic,blue crabs,Callinectes sapidus,inhabit estuaries,sounds and coastal oceans and are commercially and ecologically *** crabs move in response to physical variables is important to *** monitored life stages at canal control structures,assessed gender ratios with recreational crabbing,learned from crabbers,and studied movements of tagged crabs in a canal connecting Lake Mattamuskeet to the Pamlico *** enter the lake through two of 4 canals connecting to the *** migrate out through one *** lake standing population is about 70% *** of 240 crabs in August 2012 and 102 crabs in October 2014 were quantified using RFID tags with co-located meteorological and oceanographic ***-spawning females and males are *** released in the canal move in response to changes in water depth and go with the flow,toward the Pamlico Sound(summer 76% and fall 78%).What crabbers describe as a fall migration appears to be concentration of crabs in warmer deeper canals and then southern movement with flow generated by strong north *** be effective,management strategies like migratory corridors require understanding of crab movements.

关键词： Crabs Meteorology Oceanography Movement foraging Migration RFID Tagging Life History

What elk, wolves and caterpillars have in common—The perfect forager theorem

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Open Journal of Ecology 2013年第2期3卷 133-144页

作者： Piotr Weclaw Robert J. Hudson Parks Division Alberta Tourism Parks and Recreation Edmonton Canada Renewable Resources Faculty of Agricultural Life and Environmental Sciences University of Alberta Edmonton Canada

It is widely accepted that the Marginal Value Theorem (MVT) describes optimal foraging strategies of animals and the mechanism proposed by the MVT has been supported by a number of field observations. However, findings of many researchers indicate that in natural conditions foragers do not always behave according to the MVT. To address this inconsistency, in a series of computer simulation experiments, we examined the behaviour of four types of foragers having specific foraging efficiencies and using the MVT strategies in 15 different landscapes in an ideal environment (no intra-and inter-specific interactions). We used data on elk (Cervus elaphus) to construct our virtual forager. Contrary to the widely accepted understanding of the MVT (residence time in a patch should be longer in environments where travel time between patches is longer) we found that in environments with the same average patch quality and varying average travel times between patches, patch residence times of some foragers are not affected by travel times. Based on our analysis we propose a mechanism responsible for this observation and formulate the perfect forager theorem (PFT). We also introduce the concepts of a foraging coefficient (F) and foragers’ hub (α), and propose a model to describe the relationship between the perfect forager and all other forager types.

关键词： Resource Optimization Optimal Use of Resources Optimal foraging Perfect Forager Theorem Functional Response Curve Ecological Modeling Marginal Value Theorem foraging Behaviour Computer Model SeekSMART