Intraspecific pod and seed trait variation of two herbaceous legume seeds in response to competing neighbours and nutrient resource abundance

Abstract Understanding the within- and among-population distribution of trait variation within seed collections may provide a means to approximate standing genetic variation and inform plant conservation. This study aimed to estimate population- and family-level seed trait variability for existing seed collections of Torrey pine (Pinus torreyana), and to use these data to guide sampling of future collections. We quantified variation in 14 seed morphological traits and seedling emergence within and among Torrey pine populations. Using a simulation-based approach, we used estimates of within-population variance to assess the number of maternal families required to capture 95 % of trait variation within each existing seed collection. Substantial structure was observed both within and among Torrey pine populations, with island and mainland seeds varying in seed size and seed coat thickness. Despite morphological differences, seedling emergence was similar across populations. Simulations revealed that 83 % and 71 % of all maternal families within island and mainland seed collections respectively needed to be resampled to capture 95 % of seed trait variation within existing collections. From a conservation perspective, our results indicate that to optimize genetic diversity captured in Torrey pine seed collections, maximizing the number of maternal families sampled within each population will be necessary.

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Geographic patterns of seed trait variation in an invasive species: how much can close populations differ?

Oecologia ◽

10.1007/s00442-021-04971-2 ◽

2021 ◽

Author(s):

Erola Fenollosa ◽

Laia Jené ◽

Sergi Munné-Bosch

Keyword(s):

Invasive Species ◽

Seed Production ◽

Anthropogenic Pressure ◽

Seed Traits ◽

Trait Variation ◽

Interpopulation Variability ◽

Seed Trait ◽

Bioclimatic Variables ◽

Human Density ◽

Trait Variability

AbstractSeeds play a major role in plant species persistence and expansion, and therefore they are essential when modeling species dynamics. However, homogeneity in seed traits is generally assumed, underestimating intraspecific trait variability across the geographic space, which might bias species success models. The aim of this study was to evaluate the existence and consequences of interpopulation variability in seed traits of the invasive species Carpobrotus edulis at different geographical scales. We measured seed production, morphology, vigour and longevity of nine populations of C. edulis along the Catalan coast (NE Spain) from three differentiated zones with a human presence gradient. Geographic distances between populations were contrasted against individual and multivariate trait distances to explore trait variation along the territory, evaluating the role of bioclimatic variables and human density of the different zones. The analysis revealed high interpopulation variability that was not explained by geographic distance, as regardless of the little distance between some populations (< 0.5 km), significant differences were found in several seed traits. Seed production, germination, and persistence traits showed the strongest spatial variability up to 6000% of percent trait variability between populations, leading to differentiated C. edulis soil seed bank dynamics at small distances, which may demand differentiated strategies for a cost-effective species management. Seed trait variability was influenced by human density but also bioclimatic conditions, suggesting a potential impact of increased anthropogenic pressure and climate shifts. Geographic interpopulation trait variation should be included in ecological models and will be important for assessing species responses to environmental heterogeneity and change.

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Human Capital Accumulation and Resource Abundance

Voprosy Ekonomiki ◽

10.32609/0042-8736-2011-12-66-77 ◽

2011 ◽

pp. 66-77

Author(s):

O. Vasilieva

Keyword(s):

Economic Growth ◽

Human Capital ◽

Capital Accumulation ◽

Relevant Literature ◽

Harmful Effect ◽

Human Capital Accumulation ◽

Resource Abundance ◽

Empirical Results ◽

Theoretical Predictions ◽

Crowd Out

Does resource abundance positively affect human capital accumulation? Or, alternatively, does it «crowd out» the human capital leading to the deterioration of economic growth? The paper gives an overview of the relevant literature and discusses both theoretical and empirical results obtained regarding the connection between human capital accumulation and resource abundance. It shows that despite some theoretical predictions about the harmful effect of resource abundance on human capital accumulation, unambiguous evidence of such impact that would be robust with respect to the change of resource abundance parameter has not been obtained yet.

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Mechanisms of Resource Curse and Economic Policy

Voprosy Ekonomiki ◽

10.32609/0042-8736-2007-6-4-27 ◽

2007 ◽

pp. 4-27 ◽

Cited By ~ 11

Author(s):

V. Polterovich ◽

V. Popov ◽

A. Tonis

Keyword(s):

Real Exchange Rates ◽

Resource Curse ◽

Budget Deficits ◽

Resource Abundance ◽

Fuel Prices ◽

Use Of Resources ◽

Resource Wealth ◽

The One ◽

The Right ◽

Rich Countries

This paper compares various mechanisms of resource curse leading to a potentially inefficient use of resources; it is demonstrated that each of these mechanisms is associated with market imperfections and can be "corrected" with appropriate government policies. Empirical evidence seems to suggest that resource abundant countries have on average lower budget deficits and inflation, and higher foreign exchange reserves. Besides, lower domestic fuel prices that are typical for resource rich countries have a positive effect on long-term growth even though they are associated with losses resulting from higher energy consumption. On top of that resource abundance allows to reduce income inequalities. So, on the one hand, resource wealth turns out to be conducive to growth, especially in countries with strong institutions. However, on the other hand, resource abundance leads to corruption of institutions and to overvalued real exchange rates. On balance, there is no solid evidence that resource abundant countries grow more slowly than the others, but there is evidence that they grow more slowly than could have grown with the right policies and institutions.

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Self-other agreement in disgust sensitivity

10.31234/osf.io/dymqk ◽

2019 ◽

Author(s):

Annika Karinen ◽

Joshua M. Tybur ◽

Reinout E. de Vries

Keyword(s):

Personality Traits ◽

Political Attitudes ◽

Romantic Partners ◽

Disgust Sensitivity ◽

Trait Variation ◽

Self And Other ◽

Self Reports ◽

Moral Disgust ◽

Sexual Disgust ◽

Moral Condemnation

A broad literature indicates that pathogen, sexual, and moral disgust sensitivity relate to, among other things, political attitudes, moral condemnation, and symptoms of psychopathology. As such, instruments measuring disgust sensitivity have been widely used across subfields of psychology. Yet, surprisingly little work has examined whether self-reports in disgust sensitivity reflect systematic trait variation. Here, we present the first study to examine self-other agreement in pathogen, sexual, and moral disgust sensitivity. Romantic partners (n1 = 290), friends (n2 = 212) and acquaintances (n3 = 140) rated each other on these three domains of disgust sensitivity and on the HEXACO personality dimensions. Correlations between dyad partners’ self- and other-ratings were calculated to estimate the magnitude of self-other agreement. We found self-other agreement in all domains of disgust sensitivity (r’s of .36, .46, and .66 for moral, pathogen, and sexual disgust sensitivity, respectively), with this agreement only slightly inferred from personality perceptions (percentages mediated by HEXACO were 15%, 7%, and 33% for pathogen, sexual, and moral disgust sensitivity, respectively). These results suggest that pathogen, sexual, and moral disgust sensitivity reflect systematic trait variation that is detectable by others and distinct from broader personality traits.

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