Evidence of sex change in Ilex integra

Botany ◽  
2012 ◽  
Vol 90 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Etsuro Takagi ◽  
Katsumi Togashi
Keyword(s):  
Woody Plants ◽  
Woody Plant ◽  
Sex Change ◽  
Sex Expression ◽  
Individual Tree ◽  
Low Frequencies ◽  
Individual Level ◽  
The Individual ◽  
Male To Female ◽  
Two Populations

Sex change has been recognised in some plants. The sex change in dioecious woody plants includes a monoecious state, which means that the timing of the change is synchronous in branches or shoots but not synchronous among plants, such as in partial dioecious woody plants. To determine whether such a phenomenon is common in woody plants, we investigated the sex expression in two populations of the bird-dispersed, dioecious woody plant Ilex integra Thunb. (Aquifoliaceae), one of the climax forest species in East Asia, over 3 years. No monoecious trees or hermaphrodite flowers were observed. Sex changes were observed at low frequencies, i.e., both female to male and male to female. This study suggests that I. integra may be a complete dioecious woody plant species and that the sex change occurs at the individual level, indicating that the timing of sex change is synchronous in an individual tree.

scholarly journals Estimation of Genetic and Phenotypic Parameters for Growth Traits in a Clonal Seed Orchard of Pinus kesiya in Malawi

ISRN Forestry ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Edward Missanjo ◽  
Gift Kamanga-Thole ◽  
Vidah Manda
Keyword(s):  
Growth Traits ◽  
Seed Orchard ◽  
Direct Selection ◽  
Tree Model ◽  
Individual Tree ◽  
Individual Level ◽  
Clonal Seed Orchard ◽  
Pinus Kesiya ◽  
Individual Tree Model ◽  
The Individual

Genetic and phenotypic parameters for height, diameter at breast height (dbh), and volume were estimated for Pinus kesiya Royle ex Gordon clonal seed orchard in Malawi using an ASReml program, fitting an individual tree model. The data were from 88 clones assessed at 18, 23, 30, 35, and 40 years of age. Heritability estimates for height, dbh, and volume were moderate to high ranging from 0.19 to 0.54, from 0.14 to 0.53, and from 0.20 to 0.59, respectively, suggesting a strong genetic control of the traits at the individual level, among families, and within families. The genetic and phenotypic correlations between the growth traits were significantly high and ranged from 0.69 to 0.97 and from 0.60 to 0.95, respectively. This suggests the possibility of indirect selection in trait with direct selection in another trait. The predicted genetic gains showed that the optimal rotational age of the Pinus kesiya clonal seed orchard is 30 years; therefore, it is recommended to establish a new Pinus kesiya clonal seed orchard. However, selective harvest of clones with high breeding values in the old seed orchard should be considered so that the best parents in the old orchard can continue to contribute until the new orchard is well established.

scholarly journals Common Woody Plants of Florida Scrub Ecosystems

EDIS ◽  
2013 ◽  
Vol 2013 (4) ◽  
Author(s):  
Lynn Proenza ◽  
Michael Andreu
Keyword(s):  
Plant Species ◽  
Woody Plants ◽  
Woody Plant ◽  
Forest Resources ◽  
Individual Plant ◽  
Florida Scrub ◽  
Woody Plant Species ◽  
Fact Sheet ◽  
The Individual

The purpose of this fact sheet is to help identify a few of the more common woody plant species found in Florida’s scrub ecosystems. In the individual plant descriptions, words that appear in bold font are considered to be key field characteristics that will aid in identification of the species. This 14-page fact sheet was written by Lynn Proenza and Michael Andreu and published by the UF Department of School of Forest Resources and Conservation, October 2012. http://edis.ifas.ufl.edu/fr373

scholarly journals LEARNING, EVOLUTION AND POPULATION DYNAMICS

2008 ◽  
Vol 11 (06) ◽  
pp. 901-926 ◽  
Author(s):  
JÜRGEN JOST ◽  
WEI LI
Keyword(s):  
Population Dynamics ◽  
Population Level ◽  
Individual Performance ◽  
The Other ◽  
Individual Level ◽  
Strategy Types ◽  
The Individual ◽  
Population Effects ◽  
Two Populations ◽  
Learning Schemes

We study a complementarity game as a systematic tool for the investigation of the interplay between individual optimization and population effects and for the comparison of different strategy and learning schemes. The game randomly pairs players from opposite populations. It is symmetric at the individual level, but has many equilibria that are more or less favorable to the members of the two populations. Which of these equilibria is then attained is decided by the dynamics at the population level. Players play repeatedly, but in each round with a new opponent. They can learn from their previous encounters and translate this into their actions in the present round on the basis of strategic schemes. The schemes can be quite simple, or very elaborate. We can then break the symmetry in the game and give the members of the two populations access to different strategy spaces. Typically, simpler strategy types have an advantage because they tend to go more quickly toward a favorable equilibrium which, once reached, the other population is forced to accept. Also, populations with bolder individuals that may not fare so well at the level of individual performance may obtain an advantage toward ones with more timid players. By checking the effects of parameters such as the generation length or the mutation rate, we are able to compare the relative contributions of individual learning and evolutionary adaptations.

scholarly journals Consequences of sex change for effective population size

2018 ◽  
Vol 285 (1893) ◽  
pp. 20181702 ◽  
Author(s):  
Robin S. Waples ◽  
Stefano Mariani ◽  
Chiara Benvenuto
Keyword(s):  
Population Size ◽  
Effective Population Size ◽  
Evolutionarily Stable Strategy ◽  
Sex Ratios ◽  
Sex Change ◽  
Standard Theory ◽  
Effective Population ◽  
Potential Conflict ◽  
Individual Level ◽  
The Individual

Sequential hermaphroditism, where males change to females (protandry) or the reverse (protogyny), is widespread in animals and plants, and can be an evolutionarily stable strategy (ESS) if fecundity rises faster with age in the second sex. Sequential hermaphrodites also generally have sex ratios skewed towards the initial sex, and standard theory based on fixed sexes indicates that this should reduce effective population size ( N e ) and increase the deleterious effects of genetic drift. We show that despite having skewed sex ratios, populations that change sex at the ESS age do not have reduced N e compared with fixed-sex populations with an even sex ratio. This implies that the ability of individuals to operate as both male and female allows the population to avoid some evolutionary constraints imposed by fixed sexes. Furthermore, N e would be maximized if sex change occurred at a different (generally earlier) age than is selected for at the individual level, which suggests a potential conflict between individual and group selection. We also develop a novel method to quantify the strength of selection for sex reversal.

scholarly journals Evaluation of the condition of dendrological species in Academic park in Belgrade

2016 ◽  
pp. 19-36
Author(s):  
Katarina Mladenović ◽  
Ivan Milenković ◽  
Tatjana Ćirković-Mitrović ◽  
Ljiljana Brašanac-Bosanac
Keyword(s):  
Seed Yield ◽  
Physiological Condition ◽  
Health Condition ◽  
Deciduous Species ◽  
Individual Tree ◽  
Individual Level ◽  
Poplar Trees ◽  
Birch Trees ◽  
The Individual ◽  
Tulip Poplar

This paper presents the results of the conducted evaluation of the health condition and seed yield of the dendrological species in Academic Park in Belgrade. Both scores for each individual tree and average scores for all trees within each plant genus under observation were analyzed. The health condition of 126 trees belonging 19 genera was examined while the seed yield was assessed for the total of 132 trees. The best as-is health and physiological condition was observed in the following species: nettle trees, honey locusts, pagoda trees, cedars and individual ginkgo and tulip poplar trees. Horse chestnuts, Eastern black walnuts and birch trees proved less resilient to biotic and abiotic damages. Japanese pagoda trees had the best seed yield. There were no significant differences in fruit-bearing between the two years of research, although there were different scores at the individual level. Of all deciduous species recorded, which were prevailing, about 60% had very good seed yield in both years of monitoring, while some 20% of trees bore no fruits. Coniferous trees had higher fruit-bearing score in 2015 (47.4%) than in 2016 (43.0%), whereas about 10% of all conifers bore no fruit at all.

scholarly journals Strategies to Maximize the Wood Production in Amazon Forest

2020 ◽  
Author(s):  
Aline Canetti ◽  
Evaldo Muñoz Braz ◽  
Patricia Mattos ◽  
Renato Olivir Basso ◽  
Afonso Figueiredo Filho
Keyword(s):  
Growth Models ◽  
Tree Level ◽  
Amazon Forest ◽  
Wood Production ◽  
Annual Increment ◽  
Individual Tree ◽  
Individual Level ◽  
Forest Law ◽  
Population Maximum ◽  
The Individual

Abstract BackgroundThis study aimed to develop a procedure to determine which logging diameter would achieve optimal wood production by species, aiming to support sustainable management of the Amazon forest. Two main methodologies of analysis by species were combined: probability density function (PDF) and growth modeling. The growth models were used to derive the volume increment curves at the individual tree level. To detect the points of maximum annual increment in volume at the population tree level we used PDF with adjusted growth equations.ResultsThe population maximum annual volumetric increments occurred in smaller diameters compared to that of the individual-level. When combining shorter cutting cycles with the population biological rotation point considered as the minimum cutting diameter (MCD), we observed higher annual increments in volume than that achieved using the Brazilian law criteria (MCD = 50 cm) or other MCD tested.ConclusionThe procedure proposed may be used by forest managers and forest law-makers, aiming to maximize sustainable wood production in the Amazon forest.

Consistency in trophic strategies between populations of the Sardinian endemic salamander Speleomantes imperialis

2017 ◽  
Vol 67 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Sebastiano Salvidio ◽  
Frank Pasmans ◽  
Sergé Bogaerts ◽  
An Martel ◽  
Martijn van de Loo ◽  
...  
Keyword(s):  
Body Condition ◽  
Trophic Ecology ◽  
Dietary Habits ◽  
Condition Index ◽  
Generalist Predators ◽  
Body Condition Index ◽  
Trophic Specialization ◽  
Individual Level ◽  
The Individual ◽  
Two Populations

The study of trophic ecology of terrestrial salamanders is central for a better understanding of their adaptability and dispersal, in particular in Mediterranean ecosystems where their feeding activity is reduced because of prolonged arid periods. Terrestrial salamanders are generalist predators that feed on a large array of invertebrate prey groups, however, there are few studies comparing the feeding strategy and the trophic specialization at the individual level in conspecific populations of salamanders living in different habitats. In this study, two populations of the Sardinian endemic salamander Speleomantes imperialis were sampled in areas characterized by different climate, vegetation and geological substrate. Dietary habits, obtained by stomach flushing, and physiological condition, assessed through a body condition index, were analysed and compared between populations. The two populations displayed different diets on the basis of the taxonomic composition of prey categories, but both of them behaved as generalist predators and shared a similar body condition index. Moreover, in both populations the indices of individual trophic specialization were significantly different from null models assuming a random prey distribution among predators. Therefore, the two populations were largely composed by individually specialized salamanders. Overall, these findings are in good agreement with other studies on the trophic ecology of top predators and in particular of terrestrial salamanders. The realized trophic strategies, i.e. generalist at the population and specialist at the individual level, were highly consistent geographically and the two populations exploited the different arrays of prey found in their environments similarly.

Differential Effects of Competence and Morality on Self-Esteem at the Individual and the Collective Level

2020 ◽  
Vol 51 (3) ◽  
pp. 183-198
Author(s):  
Wiktor Soral ◽  
Mirosław Kofta
Keyword(s):  
Self Esteem ◽  
Differential Effects ◽  
Individual Level ◽  
The Subject ◽  
The Individual

Abstract. The importance of various trait dimensions explaining positive global self-esteem has been the subject of numerous studies. While some have provided support for the importance of agency, others have highlighted the importance of communion. This discrepancy can be explained, if one takes into account that people define and value their self both in individual and in collective terms. Two studies ( N = 367 and N = 263) examined the extent to which competence (an aspect of agency), morality, and sociability (the aspects of communion) promote high self-esteem at the individual and the collective level. In both studies, competence was the strongest predictor of self-esteem at the individual level, whereas morality was the strongest predictor of self-esteem at the collective level.

Metonymy in Dance: Ballet Bunheads Take a Cognitive Turn

2019 ◽  
Vol 37 (1) ◽  
pp. 18-34
Author(s):  
Edward C. Warburton
Keyword(s):  
Identity Formation ◽  
Cognitive Science ◽  
Artistic Development ◽  
Individual Level ◽  
Figures Of Speech ◽  
Self Image ◽  
Level I ◽  
Dance Educators ◽  
The Individual ◽  
Metaphor And Metonymy

This essay considers metonymy in dance from the perspective of cognitive science. My goal is to unpack the roles of metaphor and metonymy in dance thought and action: how do they arise, how are they understood, how are they to be explained, and in what ways do they determine a person's doing of dance? The premise of this essay is that language matters at the cultural level and can be determinative at the individual level. I contend that some figures of speech, especially metonymic labels like ‘bunhead’, can not only discourage but dehumanize young dancers, treating them not as subjects who dance but as objects to be danced. The use of metonymy to sort young dancers may undermine the development of healthy self-image, impede strong identity formation, and retard creative-artistic development. The paper concludes with a discussion of the influence of metonymy in dance and implications for dance educators.

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