Multi-level phenotypic plasticity and the persistence of seagrasses along environmental gradients in a subtropical lagoon

2019 ◽  
Vol 157 ◽  
pp. 24-32 ◽  
Author(s):  
Manuel Vivanco Bercovich ◽  
Nadine Schubert ◽  
Antonella C. Almeida Saá ◽  
João Silva ◽  
Paulo A. Horta
Keyword(s):  
Phenotypic Plasticity ◽  
Environmental Gradients ◽  
Multi Level ◽  
Subtropical Lagoon

scholarly journals Phenotypic plasticity can reverse the relative extent of intra- and interspecific variability across a thermal gradient

2021 ◽  
Vol 288 (1953) ◽  
pp. 20210428
Author(s):  
Staffan Jacob ◽  
Delphine Legrand
Keyword(s):  
Phenotypic Plasticity ◽  
Thermal Gradient ◽  
Environmental Gradients ◽  
Intraspecific Variability ◽  
Functional Trait ◽  
Ecosystem Functions ◽  
Interspecific Variability ◽  
Ciliate Species ◽  
Relative Extent ◽  
Trait Variability

Intra- and interspecific variability can both ensure ecosystem functions. Generalizing the effects of individual and species assemblages requires understanding how much within and between species trait variation is genetically based or results from phenotypic plasticity. Phenotypic plasticity can indeed lead to rapid and important changes of trait distributions, and in turn community functionality, depending on environmental conditions, which raises a crucial question: could phenotypic plasticity modify the relative importance of intra- and interspecific variability along environmental gradients? We quantified the fundamental niche of five genotypes in monocultures for each of five ciliate species along a wide thermal gradient in standardized conditions to assess the importance of phenotypic plasticity for the level of intraspecific variability compared to differences between species. We showed that phenotypic plasticity strongly influences trait variability and reverses the relative extent of intra- and interspecific variability along the thermal gradient. Our results show that phenotypic plasticity may lead to either increase or decrease of functional trait variability along environmental gradients, making intra- and interspecific variability highly dynamic components of ecological systems.

scholarly journals Chromatin structure changes in Daphnia populations upon exposure to environmental cues – or – The discovery of Wolterecks “Matrix”

2019 ◽  
Author(s):  
Ronaldo de Carvalho Augusto ◽  
Aki Minoda ◽  
Oliver Rey ◽  
Céline Cosseau ◽  
Cristian Chaparro ◽  
...  
Keyword(s):  
Phenotypic Plasticity ◽  
Chromatin Structure ◽  
Environmental Gradients ◽  
Gene Mutations ◽  
Reaction Norms ◽  
Environmental Cues ◽  
Global Changes ◽  
Open Chromatin ◽  
Norm Of Reaction ◽  
Structure Changes

AbstractPhenotypic plasticity is an important feature of biological systems that is likely to play a major role in the future adaptation of organisms to the ongoing global changes. It may allow an organism to produce alternative phenotypes in responses to environmental cues. Modifications in the phenotype can be reversible but are sometimes enduring and can even span over generations. The notion of phenotypic plasticity was conceptualized in the early 20th century by Richard Woltereck. He introduced the idea that the combined relations of a phenotypic character and all environmental gradients that influence on it can be defined as “norm of reaction”. Norms of reaction are specific to species and to lineages within species, and they are heritable. He postulated that reaction norms can progressively be shifted over generations depending on the environmental conditions. One of his biological models was the water-flee daphnia. Woltereck proposed that enduring phenotypic modifications and gene mutations could have similar adaptive effects, and he postulated that their molecular bases would be different. Mutations occurred in genes, while enduring modifications were based on something he called the Matrix. He suggested that this matrix (i) was associated with the chromosomes, (ii) that it was heritable, (iii) it changed during development of the organisms, and (iv) that changes of the matrix could be simple chemical substitutions of an unknown, but probably polymeric molecule. We reasoned that the chromatin has all postulated features of this matrix and revisited Woltereck’s classical experiments with daphnia. We developed a robust and rapid ATAC-seq technique that allows for analyzing chromatin of individual daphnia and show here (i) that this technique can be used with minimal expertise in molecular biology, and (ii) we used it to identify open chromatin structure in daphnia exposed to different environmental cues. Our result indicates that chromatin structure changes consistently in daphnia upon this exposure confirming Woltereck’s classical postulate.

scholarly journals Translating environmental gradients into discontinuous reaction norms via hormone signalling in a polyphenic butterfly

2010 ◽  
Vol 278 (1706) ◽  
pp. 789-797 ◽  
Author(s):  
Vicencio Oostra ◽  
Maaike A. de Jong ◽  
Brandon M. Invergo ◽  
Fanja Kesbeke ◽  
Franziska Wende ◽  
...  
Keyword(s):  
Phenotypic Plasticity ◽  
Hormonal Regulation ◽  
Environmental Gradients ◽  
Developmental Trajectories ◽  
Reaction Norms ◽  
Bicyclus Anynana ◽  
Linear Temperature ◽  
Linear Temperature Gradient ◽  
Adult Fitness ◽  
Hormone Signalling

Polyphenisms—the expression of discrete phenotypic morphs in response to environmental variation—are examples of phenotypic plasticity that may potentially be adaptive in the face of predictable environmental heterogeneity. In the butterfly Bicyclus anynana , we examine the hormonal regulation of phenotypic plasticity that involves divergent developmental trajectories into distinct adult morphs for a suite of traits as an adaptation to contrasting seasonal environments. This polyphenism is induced by temperature during development and mediated by ecdysteroid hormones. We reared larvae at separate temperatures spanning the natural range of seasonal environments and measured reaction norms for ecdysteroids, juvenile hormones (JHs) and adult fitness traits. Timing of peak ecdysteroid, but not JH titres, showed a binary response to the linear temperature gradient. Several adult traits (e.g. relative abdomen mass) responded in a similar, dimorphic manner, while others (e.g. wing pattern) showed a linear response. This study demonstrates that hormone dynamics can translate a linear environmental gradient into a discrete signal and, thus, that polyphenic differences between adult morphs can already be programmed at the stage of hormone signalling during development. The range of phenotypic responses observed within the suite of traits indicates both shared regulation and independent, trait-specific sensitivity to the hormone signal.

Phenotypic plasticity and gene diversity in Pistacia lentiscus L. along environmental gradients in Israel

2008 ◽  
Vol 4 (4) ◽  
pp. 777-785 ◽  
Author(s):  
Sagi Nahum ◽  
Moshe Inbar ◽  
Gidi Ne’eman ◽  
Rachel Ben-Shlomo
Keyword(s):  
Phenotypic Plasticity ◽  
Environmental Gradients ◽  
Gene Diversity ◽  
Pistacia Lentiscus

Verlaufsanalyse wöchentlicher Selbst- und Fremdeinschätzungen in der Langzeittherapie suchtkranker Jugendlicher

2019 ◽  
Vol 47 (2) ◽  
pp. 126-137
Author(s):  
Ferdinand Keller ◽  
Tatjana Stadnitski ◽  
Jakob Nützel ◽  
Renate Schepker
Keyword(s):  
Allen Vier ◽  
Multi Level

Zusammenfassung. Fragestellung: Über Veränderungen in der emotionalen Befindlichkeit von Jugendlichen während einer Suchttherapie ist wenig bekannt. Methode: Die Jugendlichen füllten wöchentlich einen entsprechenden Fragebogen aus, analog ihre Bezugsbetreuer eine parallelisierte Kurzfassung. Von 42 Jugendlichen liegen insgesamt 853 Bogen und von den Bezugsbetreuern 708 Bogen vor. Die Fragebogen wurden zunächst faktorenanalytisch hinsichtlich ihrer Dimensionalität ausgewertet, anschließend wurden gruppenbezogene Verlaufsanalysen (Multi-Level-Modelle) und Abhängigkeitsanalysen auf Einzelfallebene (Zeitreihenanalysen) durchgeführt. Ergebnisse: Im Jugendlichenfragebogen ergaben sich vier Faktoren: negative Befindlichkeit, Wertschätzung von Therapie/Betreuung, Motivation und Suchtdynamik. Die Übereinstimmung zwischen den Jugendlichen- und der (einfaktoriellen) Betreuereinschätzung fiel insgesamt niedrig bis mäßig aus, brachte aber auf Einzelfallebene differenziertere Ergebnisse. Im Verlauf nahmen die Werte auf allen vier Jugendlichenskalen ab. Einzig der Verlauf der Wertschätzung in der Eingewöhnungsphase war prädiktiv für den späteren Abbruch der Maßnahme: Bei den Abbrechern nahm die Wertschätzung ab, während sie bei den Beendern initial stieg. Schlussfolgerungen: Der bedeutsamste Faktor in Bezug auf die Therapiebeendigung suchtkranker Jugendlicher scheint die Wertschätzung von Therapie/Betreuung zu sein, während die Motivation jugendtypische Schwankungen aufweist. Der Suchtdynamik kam eine deutlich weniger bedeutende Rolle zu als allgemein angenommen. Programme in der Langzeittherapie sollten die Wertschätzung von Therapie/Betreuung künftig mehr fokussieren als die Suchtdynamik.

A Multi-level Measure Of Safety Climate And Associations With Safety Behaviors In The Fire Service

2017 ◽  
Author(s):  
Todd D. Smith ◽  
Mari-Amanda Dyal ◽  
Yongjia Pu ◽  
Stephanie Dickinson ◽  
David M. DeJoy
Keyword(s):  
Safety Climate ◽  
Fire Service ◽  
Safety Behaviors ◽  
Multi Level
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