scholarly journals The impact of individual variation on abrupt collapses in mutualistic networks

2021 ◽  
Author(s):  
Gaurav Baruah
Keyword(s):  
Individual Variation ◽  
Mutualistic Networks ◽  
The Impact

scholarly journals A Multiscale Review of Behavioral Variation in Collective Foraging Behavior in Honey Bees

Insects ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 370 ◽  
Author(s):  
Natalie J. Lemanski ◽  
Chelsea N. Cook ◽  
Brian H. Smith ◽  
Noa Pinter-Wollman
Keyword(s):  
Individual Differences ◽  
Foraging Behavior ◽  
Collective Behavior ◽  
Individual Variation ◽  
Honey Bees ◽  
Multiple Scales ◽  
Model System ◽  
Bee Foraging ◽  
Collective Foraging ◽  
The Impact

The emergence of collective behavior from local interactions is a widespread phenomenon in social groups. Previous models of collective behavior have largely overlooked the impact of variation among individuals within the group on collective dynamics. Honey bees (Apis mellifera) provide an excellent model system for exploring the role of individual differences in collective behavior due to their high levels of individual variation and experimental tractability. In this review, we explore the causes and consequences of individual variation in behavior for honey bee foraging across multiple scales of organization. We summarize what is currently known about the genetic, developmental, and neurophysiological causes of individual differences in learning and memory among honey bees, as well as the consequences of this variation for collective foraging behavior and colony fitness. We conclude with suggesting promising future directions for exploration of the genetic and physiological underpinnings of individual differences in behavior in this model system.

scholarly journals The impact of bio-logging on body weight change of the Eurasian beaver

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261453
Author(s):  
Christian Andre Robstad ◽  
Hanna Kavli Lodberg-Holm ◽  
Martin Mayer ◽  
Frank Rosell
Keyword(s):  
Body Weight ◽  
Weight Change ◽  
Individual Variation ◽  
Careful Consideration ◽  
Control Group ◽  
Large Individual ◽  
Body Weight Change ◽  
Ecological Data ◽  
Negative Impacts ◽  
The Impact

Bio-logging is a common method to collect ecological data on wild animals, but might also induce stress, reduce body condition, and alter behavior. Eurasian beavers (Castor fiber) are a semi-aquatic and nocturnal species that are challenging to observe in the wild. Bio-loggers are hence useful tools to study their behaviour and movements, but this raises concerns of potential negative impacts of tagging. To investigate the potential negative impacts of glue-on tags, we compared body weight change for tagged and untagged Eurasian beavers. We hypothesized that tagged beavers would gain less body weight compared to untagged beavers, and that weight change might be affected by tagging length, tag weight, water temperature and the season of tagging. Daily percentage body weight change in relation to initial body weight during the first capture was compared during 57 tagging periods (18±7 days) and 32 controls periods (64±47 days). Body weight change varied between the two groups, with untagged beavers on average gaining daily weight whilst tagged beavers on average lost weight daily, indicating a negative effect of tagging. The average reduction in percentage body weight change per day for tagged beavers was small (0.1 ± 0.3%), and with large individual variation. Neither tag weight, number of tagging days, nor season were important in explaining body weight change of tagged animals. In other words, we found that tagging reduced daily body weight during the tagging period but were unable to determine the mechanism(s) responsible for this decline. Detrimental effects of tagging have important implications for animal welfare and can introduce bias in data that are collected. This calls for careful consideration in the use of tags. We conclude that studies investigating the effects of tagging should consider individual variation in the effects of tagging and, where possible, compare tagged animals with a control group.

scholarly journals A functional CD8+ cell assay reveals individual variation in CD8+ cell antiviral efficacy and explains differences in human T-lymphotropic virus type 1 proviral load

2005 ◽  
Vol 86 (5) ◽  
pp. 1515-1523 ◽  
Author(s):  
Becca Asquith ◽  
Angelina J. Mosley ◽  
Anna Barfield ◽  
Sara E. F. Marshall ◽  
Adrian Heaps ◽  
...  
Keyword(s):  
Virus Type ◽  
Individual Variation ◽  
Proviral Load ◽  
Ex Vivo ◽  
Type I ◽  
T Lymphotropic Virus ◽  
Viral Burden ◽  
Infected Cells ◽  
Cd8 Cell ◽  
The Impact

The CD8+ lymphocyte response is a main component of host immunity, yet it is difficult to quantify its contribution to the control of persistent viruses. Consequently, it remains controversial as to whether CD8+ cells have a biologically significant impact on viral burden and disease progression in infections such as human immunodeficiency virus-1 and human T-lymphotropic virus type I (HTLV-I). Experiments to ascertain the impact of CD8+ cells on viral burden based on CD8+ cell frequency or specificity alone give inconsistent results. Here, an alternative approach was developed that directly quantifies the impact of CD8+ lymphocytes on HTLV-I proviral burden by measuring the rate at which HTLV-I-infected CD4+ cells were cleared by autologous CD8+ cells ex vivo. It was demonstrated that CD8+ cells reduced the lifespan of infected CD4+ cells to 1 day, considerably shorter than the 30 day lifespan of uninfected cells in vivo. Furthermore, it was shown that HTLV-I-infected individuals vary considerably in the rate at which their CD8+ cells clear infected cells, and that this was a significant predictor of their HTLV-I proviral load. Forty to 50 % of between-individual variation in HTLV-I proviral load was explained by variation in the rate at which CD8+ cells cleared infected cells. This novel approach demonstrates that CD8+ cells are a major determinant of HTLV-I proviral load. This assay is applicable to quantifying the CD8+ cell response to other viruses and malignancies and may be of particular importance in assessing vaccines.

scholarly journals The changing microRNA landscape by color and cloudiness: a cautionary tale for nipple aspirate fluid biomarker analysis

2021 ◽  
Author(s):  
Susana I. S. Patuleia ◽  
Elsken van der Wall ◽  
Carla H. van Gils ◽  
Marije F. Bakker ◽  
Agnes Jager ◽  
...  
Keyword(s):  
Mirna Expression ◽  
Individual Variation ◽  
Expression Patterns ◽  
Fold Change ◽  
Nipple Aspirate Fluid ◽  
Liquid Biopsies ◽  
Significant Differential Expression ◽  
Increased Risk ◽  
Biomarker Analysis ◽  
The Impact

Abstract Purpose Investigation of nipple aspirate fluid (NAF)-based microRNAs (miRNAs) as a potential screening tool for women at increased risk of developing breast cancer is the scope of our research. While aiming to identify discriminating NAF-miRNAs between women with different mammographic densities, we were confronted with an unexpected confounder: NAF sample appearance. Here we report and alert for the impact of NAF color and cloudiness on miRNA assessment. Methods Seven classes of NAF colors coupled with cloudiness appearance were established. Using 173 NAF samples from 154 healthy women (19 samples were bilaterally collected), the expression of 14 target and 2 candidate endogenous control (EC) miRNAs was investigated using Taqman Advanced miRNA assays to identify significant differential expression patterns between color-cloudiness classes. Inter- and intra-individual variation of miRNA expression was analyzed using the coefficient of variation (CV). Results We found that between the seven NAF classes, fold change miRNA expression differences ranged between 2.4 and 19.6 depending on the interrogated miRNA. Clear NAF samples exhibited higher miRNA expression levels compared to cloudy NAF samples with fold change differences ranging between 1.1 and 6.2. Inter-individual and intra-individual miRNA expression was fairly stable (CV < 15 %), but nevertheless impacted by NAF sample appearance. Within NAF classes, inter-individual variation was largest for green samples (CV 6-15 %) and smallest for bloody samples (CV 2-6 %). Conclusions Our data indicate that NAF color and cloudiness influence miRNA expression and should, therefore, be systematically registered using an objective color classification system. Given that sample appearance is an inherent feature of NAF, these variables should be statistically controlled for in multivariate data analyses. This cautionary note and recommendations could be of value beyond the field of NAF-miRNAs, given that variability in sample color and cloudiness is likewise observed in liquid biopsies such as urine, cerebrospinal fluid and sputum, and could thereby influence the levels of miRNAs and other biomarkers.

scholarly journals Ecological effects of a deodorant and a plain soap upon human skin bacteria

1977 ◽  
Vol 78 (1) ◽  
pp. 1-10 ◽  
Author(s):  
David J. Bibel
Keyword(s):  
Human Skin ◽  
Analysis Of Variance ◽  
Individual Variation ◽  
Staphylococcus Epidermidis ◽  
Micrococcus Luteus ◽  
Acinetobacter Calcoaceticus ◽  
Skin Bacteria ◽  
Skin Flora ◽  
Significant Difference ◽  
The Impact

SUMMARYThe effects of a commercial trichlorocarbanilide-containing deodorant soap and a commercial plain soap upon the cutaneous flora of individuals were compared. Using a cross-over design, 21 volunteers (10 women and 11 men) washed their forearms at least once a day with one soap for 3 weeks and then switched soaps for another 4 weeks use. By analysis of variance no significant difference in total colony counts was noted among individuals in their use of the two soaps. With the exception of individual variation, neither sequence of use, sex, nor any combination was influential. However, in 20 of 21 subjects an alteration in the composition of skin flora was observed. The deodorant soap, which in six cases increased total flora, tended to reduce or eliminate diphtheroids in 12 of 17 carriers (71%). Fewer kinds of bacteria were also noted. MoreStaphylococcus epidermidiswas seen with the plain soap, but washing with the deodorant soap seemed to favourAcinetobacter calcoaceticusandMicrococcus luteus.The impact of this alteration and the use of total counts to measure effectiveness of deodorant soaps were brought into question.

scholarly journals The importance of individual variation for the interpretation of behavioural studies: ethanol effects vary with basal activity level in zebrafish larvae

2021 ◽  
Author(s):  
Raissa Davis ◽  
Floris Luchtenburg ◽  
Michael Richardson ◽  
Marcel Schaaf ◽  
Christian Tudorache ◽  
...  
Keyword(s):  
Individual Variation ◽  
Ethanol Exposure ◽  
Activity Level ◽  
Laboratory Population ◽  
Swimming Velocity ◽  
Emergence Time ◽  
Basal Activity ◽  
Individual Consistency ◽  
The Impact ◽  
Over Time

AbstractStandardization and reduction of variation is key to behavioural screening of animal models in toxicological and pharmacological studies. However, individual variation in behavioural and physiological phenotypes remains in each laboratory population and can undermine the understanding of toxicological and pharmaceutical effects and their underlying mechanisms. Here, we used zebrafish (ABTL-strain) larvae to explore individual consistency in activity level and emergence time, across subsequent days of early development (6–8 dpf). We also explored the correlation between these two behavioural parameters. We found inter-individual consistency over time in activity level and emergence time, but we did not find a consistent correlation between these parameters. Subsequently, we investigated the impact of variation in activity level on the effect of a 1% ethanol treatment, suitable for our proof-of-concept case study about whether impact from pharmacological treatments might be affected by inter-individual variation in basal locomotion. The inter-individual consistency over time in activity level did not persist in this test. This was due to the velocity change from before to after exposure, which turned out to be a dynamic individual trait related to basal activity level: low-activity individuals raised their swimming velocity, while high-activity individuals slowed down, yielding diametrically opposite response patterns to ethanol exposure. We therefore argue that inter-individual consistency in basal activity level, already from 6 dpf, is an important factor to take into account and provides a practical measure to improve the power of statistical analyses and the scope for data interpretation from behavioural screening studies.

Individual variation and ecotypic niches in simulations of the impact of climatic volatility

2019 ◽  
Vol 411 ◽  
pp. 108782 ◽  
Author(s):  
George P. Malanson ◽  
R. Justin DeRose ◽  
Matthew F. Bekker
Keyword(s):  
Individual Variation ◽  
The Impact

Challenges for the Future of Functional Response Research

2021 ◽  
pp. 133-144
Author(s):  
John P. DeLong
Keyword(s):  
Food Webs ◽  
Functional Response ◽  
Individual Variation ◽  
Functional Responses ◽  
Community Interactions ◽  
Invasive Predators ◽  
The Future ◽  
Behavioral Mechanisms ◽  
Future Work ◽  
The Impact

Being recognized for more than 70 years and estimated thousands of times, with numerous analyses of compilations, it would seem there is a lot we should know about functional responses. Indeed, we know some of the ways in which functional responses vary, how foraging mechanisms combine to determine, to at least some extent, functional response parameters, and how functional responses influence community interactions from biocontrol impacts to invasive predators to food webs. I suggest, however, that there remains a considerable amount that we do not know, in particular for field-based functional responses, multi-species functional responses, individual variation, behavioral mechanisms, and the impact and evolution of underlying traits. I suggest these areas should be high priorities for future work on functional responses.

Language Contact and Language Attrition

2019 ◽  
pp. 313-328
Author(s):  
Claudia Maria Riehl
Keyword(s):  
Individual Differences ◽  
Individual Variation ◽  
Language Contact ◽  
Discourse Markers ◽  
External Factors ◽  
Language Awareness ◽  
Language Attrition ◽  
Bilingual Communities ◽  
Key Terms ◽  
The Impact

This chapter focuses on language contact phenomena typical in language attrition processes. It starts from the assumption that language contact is a bilingual practice reflecting the processing/use of language in a bilingual speaker’s repertoire. Defining key terms such as borrowing, transference, and convergence, the chapter addresses typical language contact phenomena in various language attrition settings such as lexical transference, processes of semantical restructuring, syntactic transference/convergence, morphological/phonological transfer. The chapter discusses aspects of pragmatic convergence, that is, the adoption of L2-discourse marking systems. It demonstrates that despite much individual variation there are some phenomena which typically occur in different speakers and different communities of attriters independently, that is, L1 lexemes adopting L2 meaning, instances of pivot matching, and the adoption of turn-related discourse markers. Finally, the impact of external factors, such as language awareness, attitude, and norm-orientation in bilingual communities that explain individual differences in attriters, is discussed.

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