scholarly journals Seasonality and Oldowan behavioral variability in East Africa

2021 ◽  
Author(s):  
Gonzalo José Linares Matás ◽  
James Clark
Keyword(s):  
Behavioral Flexibility ◽  
Taxonomic Composition ◽  
Behavioral Variability ◽  
Success Rates ◽  
Resource Exploitation ◽  
Wet Season ◽  
Net Returns ◽  
Lithic Assemblages ◽  
Kanjera South ◽  
Procurement Strategies

The extent, nature, and temporality of early hominin food procurement strategies has been subject to extensive debate. In this paper, we examine evidence for the seasonal scheduling of resource procurement and technological investment in the Oldowan. The mortality profiles, taxonomic composition, and taphonomy of the bovid assemblages at Kanjera South (Homa Peninsula, Kenya) and FLK-Zinj (Olduvai Gorge, Tanzania) illustrate the behavioral flexibility of Oldowan hominins, who were targeting different seasonally-vulnerable demographics. In terms of the lithic assemblages, the combined influences of high competition risks, high procurement costs, and low success rates in carcass acquisition during the dry season at FLK-Zinj may have disincentivized lithic investment, resulting in a more expedient toolkit for fast carcass processing. This pattern is reinforced by the effectiveness of unretouched flakes in defleshing tasks. In contrast, wet season plant abundance would have offered a predictable set of high-quality resources at Kanjera South, associated with low levels of competition and reduced search times. These factors appear to have fostered technological investment to reduce resource handling costs, and enhanced planning of lithic deployment throughout the landscape, as a result of more consistent net returns. While data are scarce, we also propose that the spatial patterning of Oldowan technological investment at Gona (Ethiopia) may relate to seasonal shifts in habitat availability and resource distribution. We subsequently discuss the seasonality of freshwater resources in Oldowan procurement strategies, focusing on FwJj20 (Koobi Fora, Kenya). While more analytical studies with representative sample sizes are needed, we argue that inter-assemblage differences evidence the ability of Oldowan hominins to adapt to seasonal constraints and opportunities in resource exploitation.

Phenotypic plasticity

2018 ◽  
Author(s):  
Karen D. Williams ◽  
Marla B. Sokolowski
Keyword(s):  
Gene Expression ◽  
Phenotypic Plasticity ◽  
Environmental Change ◽  
Behavioral Plasticity ◽  
Behavioral Flexibility ◽  
Insect Behavior ◽  
Behavioral Variability ◽  
Gene By Environment Interactions ◽  
Affect Gene Expression

Why is there so much variation in insect behavior? This chapter will address the sources of behavioral variability, with a particular focus on phenotypic plasticity. Variation in social, nutritional, and seasonal environmental contexts during development and adulthood can give rise to phenotypic plasticity. To delve into mechanism underlying behavioral flexibility in insects, examples of polyphenisms, a type of phenotypic plasticity, will be discussed. Selected examples reveal that environmental change can affect gene expression, which in turn can affect behavioral plasticity. These changes in gene expression together with gene-by-environment interactions are discussed to illuminate our understanding of insect behavioral plasticity.

scholarly journals Influence of peak flow changes on the macroinvertebrate drift downstream of a Brazilian hydroelectric dam

2013 ◽  
Vol 73 (4) ◽  
pp. 775-782 ◽  
Author(s):  
DMP. Castro ◽  
RM. Hughes ◽  
M. Callisto
Keyword(s):  
Peak Flow ◽  
Hydroelectric Plant ◽  
Taxonomic Composition ◽  
Dry Season ◽  
Wet Season ◽  
Peak Flows ◽  
Flow Fluctuations ◽  
Hydropower Plants ◽  
Flow Changes ◽  
Macroinvertebrate Drift

Successive daily peak flows from hydropower plants can disrupt aquatic ecosystems and alter the composition and structure of macroinvertebrates downstream. We evaluated the influence of peak flow changes on macroinvertebrate drift downstream of a hydroelectric plant as a basis for determining ecological flows that might reduce the disturbance of aquatic biota. The aim of this study was to assess the influence of flow fluctuations on the seasonal and daily drift patterns of macroinvertebrates. We collected macroinvertebrates during fixed flow rates (323 m3.s–1 in the wet season and 111 m3.s–1 in the dry season) and when peak flows fluctuated (378 to 481 m3.s–1 in the wet season, and 109 to 173 m3.s–1 in the dry season) in 2010. We collected 31,924 organisms belonging to 46 taxa in the four sampling periods. Taxonomic composition and densities of drifting invertebrates differed between fixed and fluctuating flows, in both wet and dry seasons, but family richness varied insignificantly. We conclude that macroinvertebrate assemblages downstream of dams are influenced by daily peak flow fluctuations. When making environmental flow decisions for dams, it would be wise to consider drifting macroinvertebrates because they reflect ecological changes in downstream biological assemblages.

scholarly journals Diversity of larvae of littoral Chironomidae (Diptera: Insecta) and their role as bioindicators in urban reservoirs of different trophic levels

2010 ◽  
Vol 70 (4) ◽  
pp. 995-1004 ◽  
Author(s):  
SS. Morais ◽  
J. Molozzi ◽  
AL. Viana ◽  
TH. Viana ◽  
M. Callisto
Keyword(s):  
Taxonomic Composition ◽  
Dry Season ◽  
Trophic Levels ◽  
Southeastern Brazil ◽  
Chemical Pollution ◽  
Taxonomic Richness ◽  
Wet Season ◽  
Total N ◽  
Chironomid Larvae ◽  
Chironomid Assemblages

The Chironomidae (Diptera: Insecta) have a high species richness, with species adapted to live under widely different environmental conditions. The study of the taxonomic composition of chironomid larvae and the percentage of occurrence of deformities in mouthparts, mainly in the mentum, are used in biomonitoring programmes in order to obtain information on the levels of organic and chemical pollution of aquatic ecosystems. The objective of this study was to evaluate the abundance of chironomid larvae and to quantify the occurrence of mentum deformities in the specimens collected in three urban reservoirs with different trophic levels. The reservoirs are located in the hydrographic basin of the Paraopeba River, an affluent of the São Francisco River basin (Minas Gerais State, southeastern Brazil). The Serra Azul Reservoir is oligotrophic, the Vargem das Flores Reservoir is mesotrophic, and the Ibirité Reservoir is eutrophic. Along the littoral zone of each reservoir, 30 samples were collected during each sampling campaign. Sampling was carried out every three months for one year, with two sampling campaigns during the wet season and two during the dry season in 2008. Physical and chemical parameters measured in the water column included the water depth, Secchi depth, air and water temperature, electrical conductivity, total dissolved solids, redox potential, dissolved oxygen, pH, turbidity, Total-N, Total-P, P-ortho, and chlorophyll-a. The chironomid larvae were identified to the genus level. The structure of the chironomid assemblages was evaluated based on taxonomic richness (24 genera), density, equitability, and diversity. The potential indicator taxa for each reservoir were established through an Indicator Species Analysis. The values for taxonomic richness (20 taxa), equitability (0.737), and Shannon-Wiener diversity (2.215) were highest in the Serra Azul Reservoir. Fissimentum was the indicator taxon in Serra Azul, the oligotrophic reservoir; whereas Pelomus was the indicator taxon in Vargem das Flores, and Chironomus in Ibirité. The highest percentage of mentum deformities was found during the dry season in Serra Azul (6.9%), while the lowest percentage was found during the wet season in Vargem das Flores (0.8%). The results of this study evidenced significant differences in the taxonomic composition, richness, equitability, and diversity of the chironomid assemblages in these three reservoirs of different trophic levels.

scholarly journals Behavioral flexibility of a group of bearded capuchin monkeys (Cebus libidinosus) in the National Park of Brasília (Brazil): consequences of cohabitation with visitors

2008 ◽  
Vol 68 (4) ◽  
pp. 685-693 ◽  
Author(s):  
G. Sabbatini ◽  
M. Stammati ◽  
MCH. Tavares ◽  
E. Visalberghi
Keyword(s):  
National Park ◽  
Behavioral Flexibility ◽  
Home Range Size ◽  
Food Sources ◽  
Wild Food ◽  
Capuchin Monkeys ◽  
Wet Season ◽  
Human Food ◽  
Cebus Libidinosus ◽  
The Impact

Increasing urbanization and deforestation have enhanced the opportunities of contact between humans and monkeys and the impact of human activities on primate behavior is receiving growing attention. This study explores whether activity budgets and diet of a group of capuchin monkeys (Cebus libidinosus) inhabiting the area of the swimming pools of the National Park of Brasília is affected by the presence of visitors providing food to them. During one year, both in the dry and the wet seasons, we scored capuchins' behavior via scan sampling every ten minutes. Results showed that this group spent less time foraging for wild foods than other comparable groups living in similar habitats. Moreover, capuchins relied more on human food during the dry season, when pulpy fruits were less available, than in the wet season. Our findings confirm other studies on different monkey species that have shown that access to human food decreases the time spent foraging for wild food and the home range size. They also show that capuchins are able to modify their diet, to exploit alternative food sources, and to change their activity budget in response to the availability of new food opportunities and to seasonal food availability.

Voice Therapy With Seniors: Attendance, Outcomes, and Associated Patient Characteristics

2019 ◽  
Vol 4 (5) ◽  
pp. 814-824 ◽  
Author(s):  
Bonnie E. Smith ◽  
Ruth Huntley Bahr ◽  
Hector N. Hernandez
Keyword(s):  
Outcome Data ◽  
Voice Therapy ◽  
Similar Data ◽  
Success Rates ◽  
Reflux Symptom Index ◽  
Voice Change ◽  
Related Factors ◽  
Symptom Index ◽  
Younger Patients ◽  
Unsuccessful Treatment

Purpose The purpose of this study was to determine the attendance and success rates for seniors in voice therapy, identify any contributing patient-related factors, and compare results to existing findings for younger patients. Method This retrospective study included information from the voice records of 50 seniors seen by the same speech-language pathologist in a private practice. Analysis of attendance and outcome data divided participants into 6 groups. Outcomes for Groups 1–3 (64% of patients) were considered successful (positive voice change), while outcomes for Groups 4–6 (36% of patients) were considered unsuccessful. These data were compared to similar data collected for younger adults in a previous study. Results The attendance and success rates for seniors in this study were higher than those previously reported for younger patients. Further consideration of patient factors revealed that reports of increased stress, Reflux Symptom Index scores > 13, and higher Voice Handicap Index functional subscale scores were significant in distinguishing between patients in the successful and unsuccessful treatment outcome groups. Conclusions The relatively high attendance and success rates among this sample of seniors suggest the desire to achieve voice improvement does not diminish with age, and chances for success in voice therapy among nonfrail seniors may be greater than for younger patients.

1548: Racial Disparities in Kidney-Transplant Graft Outcomes, with a Proposal to Improve Graft Success Rates

2005 ◽  
Vol 173 (4S) ◽  
pp. 419-419
Author(s):  
Constance Marks ◽  
Carlumandarlo E.B. Zaramo ◽  
Joan M. Alster ◽  
Charles Modlin
Keyword(s):  
Racial Disparities ◽  
Kidney Transplant ◽  
Success Rates ◽  
Graft Success

FIT – Do Something Different

2011 ◽  
Vol 70 (1) ◽  
pp. 25-34 ◽  
Author(s):  
Ben (C) Fletcher ◽  
Jill Hanson ◽  
Nadine Page ◽  
Karen Pine
Keyword(s):  
Weight Loss ◽  
Longitudinal Studies ◽  
Behavioral Intervention ◽  
Behavioral Flexibility ◽  
Calorie Intake ◽  
Life Skill ◽  
Behavioral Repertoire ◽  
Additional Weight

Two 3-month longitudinal studies examined weight loss following a 1-month behavioral intervention (FIT-DSD) focusing on increasing participants’ behavioral flexibility and breaking daily habits. The goal was to break the distal habits hypothesized as playing a role in unhealthy dietary and activity behaviors. The FIT-DSD intervention required participants to do something different each day and to engage in novel weekly activities to expand their behavioral repertoire. These activities were not food- or exercise-related. In Study 1, the FIT-DSD program was compared with a control condition where participants engaged in daily tasks not expected to influence behavioral flexibility. Study 2 used an active or quasicontrol group in which half the participants were also on food diets. Measures in both studies were taken pre-, post-, and post-postintervention. In Study 1, FIT-DSD participants showed greater weight loss that continued post-postintervention. In Study 2, all participants on the FIT-DSD program lost weight, weight loss continued post-postintervention, and participants who were also dieting lost no additional weight. A dose relationship was observed between increases in behavioral flexibility scores and weight loss, and this relationship was mediated by calorie intake. Corresponding reductions in BMI were also present. Increasing behavioral flexibility may be an effective approach for tackling obesity and also provides affective and potential life-skill benefits.

The Contributions of the Prelimbic Area to Behavioral Flexibility

2002 ◽  
Author(s):  
Michael E. Ragozzino ◽  
Jenna Kim ◽  
Derrick Hasstert ◽  
Nancy Minniti ◽  
Charlene Kiang
Keyword(s):  
Behavioral Flexibility
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