Phenotypic plasticity, population structure and adaptation in a young weed species with a worldwide distribution

SummaryThe colonization success of a species depends on phenotypic plasticity, adaptive potential and population structure. Assessing their relative contributions during a colonization process is challenging, and a large-scale experiment had yet to be done. In this study, we attempted to tease apart their effects on the fitness of one of the most common plant on Earth, the shepherd’s purse (Capsella bursa-pastoris), a self-fertilizing and allopolyploid weed, with a worldwide distribution. The overarching goal is to eventually understand how the shepherd’s purse extensive distribution range was established so rapidly. To do so, we carried out three common gardens, located in Europe, Asia and North America, and measured several life-history traits on field-collected accessions belonging to three distinct genetic clusters (Middle East, Europe, and Asia). Our experiment showed that (i) the success of C. bursa-pastoris is mainly due to its high degree of phenotypic plasticity; and (ii), genetic cluster effect reflected a classic pattern observed in core vs marginal populations, with the Middle Eastern cluster (putative core population) outperforming the European and Asian clusters. This study therefore revealed, in a model species, different relative contributions of plasticity and adaptation to fitness, depending on the population and the time since colonization occurred.

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Marsh rabbit mortalities tie pythons to the precipitous decline of mammals in the Everglades

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.0120 ◽

2015 ◽

Vol 282 (1805) ◽

pp. 20150120 ◽

Cited By ~ 39

Author(s):

Robert A. McCleery ◽

Adia Sovie ◽

Robert N. Reed ◽

Mark W. Cunningham ◽

Margaret E. Hunter ◽

...

Keyword(s):

National Park ◽

Large Scale ◽

Ongoing Debate ◽

Faunal Communities ◽

Python Molurus ◽

Scale Experiment ◽

Precipitous Decline ◽

Python Molurus Bivittatus ◽

The Impact ◽

Ecological Functioning

To address the ongoing debate over the impact of invasive species on native terrestrial wildlife, we conducted a large-scale experiment to test the hypothesis that invasive Burmese pythons ( Python molurus bivittatus ) were a cause of the precipitous decline of mammals in Everglades National Park (ENP). Evidence linking pythons to mammal declines has been indirect and there are reasons to question whether pythons, or any predator, could have caused the precipitous declines seen across a range of mammalian functional groups. Experimentally manipulating marsh rabbits, we found that pythons accounted for 77% of rabbit mortalities within 11 months of their translocation to ENP and that python predation appeared to preclude the persistence of rabbit populations in ENP. On control sites, outside of the park, no rabbits were killed by pythons and 71% of attributable marsh rabbit mortalities were classified as mammal predations. Burmese pythons pose a serious threat to the faunal communities and ecological functioning of the Greater Everglades Ecosystem, which will probably spread as python populations expand their range.

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Gender differences in trust and reciprocity: evidence from a large-scale experiment with heterogeneous subjects

Applied Economics ◽

10.1080/00036846.2015.1019036 ◽

2015 ◽

Vol 47 (36) ◽

pp. 3825-3838 ◽

Cited By ~ 12

Author(s):

Marcus Dittrich

Keyword(s):

Gender Differences ◽

Large Scale ◽

Trust And Reciprocity ◽

Scale Experiment

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Evidence for a large-scale population structure among accessions of Arabidopsis thaliana: possible causes and consequences for the distribution of linkage disequilibrium

Molecular Ecology ◽

10.1111/j.1365-294x.2006.02865.x ◽

2006 ◽

Vol 15 (6) ◽

pp. 1507-1517 ◽

Cited By ~ 90

Author(s):

MARIE-FRANCE OSTROWSKI ◽

JACQUES DAVID ◽

SYLVAIN SANTONI ◽

HEATHER MCKHANN ◽

XAVIER REBOUD ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Population Structure ◽

Linkage Disequilibrium ◽

Large Scale ◽

Scale Population

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Large scale experiment and case study

Soft Soil Engineering ◽

10.1201/9781439833926.pt4 ◽

2006 ◽

pp. 219-364

Keyword(s):

Large Scale ◽

Scale Experiment

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Fooled by facts: quantifying anchoring bias through a large-scale experiment

Journal of Computational Social Science ◽

10.1007/s42001-021-00158-0 ◽

2022 ◽

Author(s):

Taha Yasseri ◽

Jannie Reher

Keyword(s):

Decision Making ◽

Treatment Group ◽

Field Experiment ◽

Empirical Evidence ◽

Large Scale ◽

Complex Relationship ◽

Great Care ◽

The Future ◽

Anchoring Bias ◽

Scale Experiment

AbstractThrough a large-scale online field experiment, we provide new empirical evidence for the presence of the anchoring bias in people’s judgement due to irrational reliance on a piece of information that they are initially given. The comparison of the anchoring stimuli and respective responses across different tasks reveals a positive, yet complex relationship between the anchors and the bias in participants’ predictions of the outcomes of events in the future. Participants in the treatment group were equally susceptible to the anchors regardless of their level of engagement, previous performance, or gender. Given the strong and ubiquitous influence of anchors quantified here, we should take great care to closely monitor and regulate the distribution of information online to facilitate less biased decision making.

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Habitat Evaluation on Scour Hole Downflow Low Drop Structure Types Using Large-Scale Experiment

Engineering ◽

10.4236/eng.2012.49071 ◽

2012 ◽

Vol 04 (09) ◽

pp. 557-567 ◽

Cited By ~ 1

Author(s):

Joongu Kang ◽

Changsung Kim ◽

Sanghwa Jung ◽

Hongkoo Yeo

Keyword(s):

Large Scale ◽

Habitat Evaluation ◽

Scour Hole ◽

Scale Experiment ◽

Drop Structure

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Face Perception Deficits in Developmental Prosopagnosia

10.26686/wgtn.16416717 ◽

2021 ◽

Author(s):

◽

Ella Macaskill

Keyword(s):

Face Recognition ◽

Face Perception ◽

Test Performance ◽

Large Scale ◽

Memory Deficits ◽

Face Memory ◽

The Face ◽

Component Processes ◽

Severe Difficulty ◽

Scale Experiment

<p>Face recognition is a fundamental cognitive function that is essential for social interaction – yet not everyone has it. Developmental prosopagnosia is a lifelong condition in which people have severe difficulty recognising faces but have normal intellect and no brain damage. Despite much research, the component processes of face recognition that are impaired in developmental prosopagnosia are not well understood. Two core processes are face perception, being the formation of visual representations of a currently seen face, and face memory, being the storage, maintenance, and retrieval of those representations. Most studies of developmental prosopagnosia focus on face memory deficits, but a few recent studies indicate that face perception deficits might also be important. Characterising face perception in developmental prosopagnosia is crucial for a better understanding of the condition. In this thesis, I addressed this issue in a large-scale experiment with 108 developmental prosopagnosics and 136 matched controls. I assessed face perception abilities with multiple measures and ran a broad range of analyses to establish the severity, scope, and nature of face perception deficits in developmental prosopagnosia. Three major results stand out. First, face perception deficits in developmental prosopagnosia were severe, and could be comparable in size to face memory deficits. Second, the face perception deficits were widespread, affecting the whole sample rather than a subset of individuals. Third, the deficits were mainly driven by impairments to mechanisms specialised for processing upright faces. Further analyses revealed several other features of the deficits, including the use of atypical and inconsistent strategies for perceiving faces, difficulties matching the same face across different pictures, equivalent impact of lighting and viewpoint variations in face images, and atypical perceptual and non-perceptual components of test performance. Overall, my thesis shows that face perception deficits are more central to developmental prosopagnosia than previously thought and motivates further research on the issue.</p>

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