scholarly journals Mechanisms of a locally adaptive shift in allocation among growth, reproduction, and herbivore resistance in Mimulus guttatus

2018 ◽  
Author(s):  
David B. Lowry ◽  
Damian Popovic ◽  
Darlene J. Brennan ◽  
Liza M. Holeski
Keyword(s):  
Environmental Gradients ◽  
Evolutionary Divergence ◽  
Mimulus Guttatus ◽  
Herbivore Resistance ◽  
Substantial Impact ◽  
Plant Resource ◽  
Adaptive Shift ◽  
Locally Adaptive ◽  
Phytochemical Compounds ◽  
Developmental Divergence

ABSTRACTEnvironmental gradients can drive adaptive evolutionary shifts in plant resource allocation among growth, reproduction, and herbivore resistance. However, few studies have attempted to connect these adaptations to underlying physiological and genetic mechanisms. Here, we evaluate potential mechanisms responsible for a coordinated locally adaptive shift between growth, reproduction, and herbivore defense in the yellow monkeyflower, Mimulus guttatus. Through manipulative laboratory experiments we found that gibberellin (GA) growth hormones may play a role in the developmental divergence between perennial and annual ecotypes of M. guttatus. Further, we detected an interaction between a locally adaptive chromosomal inversion, DIV1, and GA addition. This finding is consistent with the inversion contributing to the evolutionary divergence between inland annual and coastal perennial ecotypes by reducing GA biosynthesis/activity in perennials. Finally, we found evidence that the DIV1 inversion is partially responsible for a coordinated shift in the divergence of growth, reproduction, and herbivore resistance traits between coastal perennial and inland annual M. guttatus. The inversion has already been established to have a substantial impact on the life-history shift between long-term growth and rapid reproduction. Here, we demonstrate that the DIV1 inversion also has sizable impacts on both the total abundance and composition of phytochemical compounds involved in herbivore resistance.

scholarly journals Mechanisms of a locally adaptive shift in allocation among growth, reproduction, and herbivore resistance in Mimulus guttatus *

Evolution ◽  
2019 ◽  
Vol 73 (6) ◽  
pp. 1168-1181 ◽  
Author(s):  
David B. Lowry ◽  
Damian Popovic ◽  
Darlene J. Brennan ◽  
Liza M. Holeski
Keyword(s):  
Mimulus Guttatus ◽  
Herbivore Resistance ◽  
Adaptive Shift ◽  
Locally Adaptive

scholarly journals Evolutionary origins for ecological patterns in space

2020 ◽  
Vol 117 (30) ◽  
pp. 17482-17490 ◽  
Author(s):  
Mark C. Urban ◽  
Sharon Y. Strauss ◽  
Fanie Pelletier ◽  
Eric P. Palkovacs ◽  
Mathew A. Leibold ◽  
...  
Keyword(s):  
Local Adaptation ◽  
Environmental Gradients ◽  
Spatial Scales ◽  
Keystone Species ◽  
Future Research ◽  
Evolutionary Divergence ◽  
Patch Selection ◽  
Fully Integrated ◽  
Evolutionary Origins ◽  
Ecological Patterns

Historically, many biologists assumed that evolution and ecology acted independently because evolution occurred over distances too great to influence most ecological patterns. Today, evidence indicates that evolution can operate over a range of spatial scales, including fine spatial scales. Thus, evolutionary divergence across space might frequently interact with the mechanisms that also determine spatial ecological patterns. Here, we synthesize insights from 500 eco-evolutionary studies and develop a predictive framework that seeks to understand whether and when evolution amplifies, dampens, or creates ecological patterns. We demonstrate that local adaptation can alter everything from spatial variation in population abundances to ecosystem properties. We uncover 14 mechanisms that can mediate the outcome of evolution on spatial ecological patterns. Sometimes, evolution amplifies environmental variation, especially when selection enhances resource uptake or patch selection. The local evolution of foundation or keystone species can create ecological patterns where none existed originally. However, most often, we find that evolution dampens existing environmental gradients, because local adaptation evens out fitness across environments and thus counteracts the variation in associated ecological patterns. Consequently, evolution generally smooths out the underlying heterogeneity in nature, making the world appear less ragged than it would be in the absence of evolution. We end by highlighting the future research needed to inform a fully integrated and predictive biology that accounts for eco-evolutionary interactions in both space and time.

scholarly journals QTL × environment interactions underlie adaptive divergence in switchgrass across a large latitudinal gradient

2019 ◽  
Vol 116 (26) ◽  
pp. 12933-12941 ◽  
Author(s):  
David B. Lowry ◽  
John T. Lovell ◽  
Li Zhang ◽  
Jason Bonnette ◽  
Philip A. Fay ◽  
...  
Keyword(s):  
Local Adaptation ◽  
Panicum Virgatum ◽  
Environmental Gradients ◽  
Adaptive Divergence ◽  
Multiple Loci ◽  
Trade Offs ◽  
Locally Adaptive ◽  
Trait Locus ◽  
Benefits And Costs ◽  
Transplant Experiments

Local adaptation is the process by which natural selection drives adaptive phenotypic divergence across environmental gradients. Theory suggests that local adaptation results from genetic trade-offs at individual genetic loci, where adaptation to one set of environmental conditions results in a cost to fitness in alternative environments. However, the degree to which there are costs associated with local adaptation is poorly understood because most of these experiments rely on two-site reciprocal transplant experiments. Here, we quantify the benefits and costs of locally adaptive loci across 17° of latitude in a four-grandparent outbred mapping population in outcrossing switchgrass (Panicum virgatumL.), an emerging biofuel crop and dominant tallgrass species. We conducted quantitative trait locus (QTL) mapping across 10 sites, ranging from Texas to South Dakota. This analysis revealed that beneficial biomass (fitness) QTL generally incur minimal costs when transplanted to other field sites distributed over a large climatic gradient over the 2 y of our study. Therefore, locally advantageous alleles could potentially be combined across multiple loci through breeding to create high-yielding regionally adapted cultivars.

Structural changes in the antennapedia complex of Drosophila pseudoobscura.

Genetics ◽  
1993 ◽  
Vol 134 (1) ◽  
pp. 319-330
Author(s):  
F M Randazzo ◽  
M A Seeger ◽  
C A Huss ◽  
M A Sweeney ◽  
J K Cecil ◽  
...  
Keyword(s):  
Structural Changes ◽  
Genetic Regulation ◽  
Drosophila Pseudoobscura ◽  
Evolutionary Divergence ◽  
Closely Related Species ◽  
Substantial Impact ◽  
Evolutionary Changes ◽  
Gene Complexes ◽  
Deformed Gene ◽  
Insight Into

Abstract The discovery of the striking positional conservation between the Antennapedia and Bithorax homeotic gene complexes (ANT-C and BX-C) in Drosophila melanogaster and the murine Hox and human HOX clusters has had a substantial impact on our understanding of the evolution of development and its genetic regulation. Structural differences do exist among the mammalian Hox complexes and the ANT-C in D. melanogaster. To gain further insight into the evolutionary changes among these complexes, the ANT-C was cloned in the closely related species, Drosophila pseudoobscura. The overall structure of the ANT-C in D. pseudoobscura is highly similar to its D. melanogaster counterpart; however, two differences in the organization of the ANT-C have been identified. First, the z2 gene, a member of the ANT-C in D. melanogaster, is not present in the D. pseudoobscura ANT-C and is possibly absent from the D. pseudoobscura genome. Second, the orientation of the Deformed gene is inverted in D. pseudoobscura, providing it with a 5' to 3' direction of transcription identical to the remaining ANT-C homeobox genes with the exception of fushi tarazu. These differences demonstrate that subtle changes can occur in ANT-C structure during relatively short periods of evolutionary divergence, although the fundamental organization of the complex is conserved. These observations and others suggest that the complex is not absolutely rigid but that selective pressures have maintained this organization of genes for some functional reason that remains elusive.

Drivers of diversity gradients of a highly mobile marine assemblage in a mesoscale seascape

2020 ◽  
Vol 638 ◽  
pp. 149-164
Author(s):  
GM Svendsen ◽  
M Ocampo Reinaldo ◽  
MA Romero ◽  
G Williams ◽  
A Magurran ◽  
...  
Keyword(s):  
Environmental Gradients ◽  
Regression Tree ◽  
Demersal Fish ◽  
Open Ocean ◽  
Shared Resources ◽  
Thermal Front ◽  
Boosted Regression Tree ◽  
Diversity Gradients ◽  
Α Diversity ◽  
Bottom Depth

With the unprecedented rate of biodiversity change in the world today, understanding how diversity gradients are maintained at mesoscales is a key challenge. Drawing on information provided by 3 comprehensive fishery surveys (conducted in different years but in the same season and with the same sampling design), we used boosted regression tree (BRT) models in order to relate spatial patterns of α-diversity in a demersal fish assemblage to environmental variables in the San Matias Gulf (Patagonia, Argentina). We found that, over a 4 yr period, persistent diversity gradients of species richness and probability of an interspecific encounter (PIE) were shaped by 3 main environmental gradients: bottom depth, connectivity with the open ocean, and proximity to a thermal front. The 2 main patterns we observed were: a monotonic increase in PIE with proximity to fronts, which had a stronger effect at greater depths; and an increase in PIE when closer to the open ocean (a ‘bay effect’ pattern). The originality of this work resides on the identification of high-resolution gradients in local, demersal assemblages driven by static and dynamic environmental gradients in a mesoscale seascape. The maintenance of environmental gradients, specifically those associated with shared resources and connectivity with an open system, may be key to understanding community stability.

Elucidating the Weakly Reversible Cs-Pb-Br Perovskite Nanocrystal Reaction Network with High-Throughput Maps and Transformations

2020 ◽  
Author(s):  
Jakob Dahl ◽  
Xingzhi Wang ◽  
Xiao Huang ◽  
Emory Chan ◽  
Paul Alivisatos
Keyword(s):  
High Throughput ◽  
Dynamic Equilibrium ◽  
Reaction Network ◽  
Substantial Impact ◽  
Equilibrium Behavior ◽  
Automated Method ◽  
Lead Bromide ◽  
Different Shapes ◽  
Complex Chemistry ◽  
Lead Halide

<p>Advances in automation and data analytics can aid exploration of the complex chemistry of nanoparticles. Lead halide perovskite colloidal nanocrystals provide an interesting proving ground: there are reports of many different phases and transformations, which has made it hard to form a coherent conceptual framework for their controlled formation through traditional methods. In this work, we systematically explore the portion of Cs-Pb-Br synthesis space in which many optically distinguishable species are formed using high-throughput robotic synthesis to understand their formation reactions. We deploy an automated method that allows us to determine the relative amount of absorbance that can be attributed to each species in order to create maps of the synthetic space. These in turn facilitate improved understanding of the interplay between kinetic and thermodynamic factors that underlie which combination of species are likely to be prevalent under a given set of conditions. Based on these maps, we test potential transformation routes between perovskite nanocrystals of different shapes and phases. We find that shape is determined kinetically, but many reactions between different phases show equilibrium behavior. We demonstrate a dynamic equilibrium between complexes, monolayers and nanocrystals of lead bromide, with substantial impact on the reaction outcomes. This allows us to construct a chemical reaction network that qualitatively explains our results as well as previous reports and can serve as a guide for those seeking to prepare a particular composition and shape. </p>

The Digital Divide and K-12 Student Computer Use

10.28945/2926 ◽  
2005 ◽  
Author(s):  
James N. Morgan ◽  
Craig A. VanLengen
Keyword(s):  
Digital Divide ◽  
Computer Use ◽  
Census Data ◽  
Internet Access ◽  
Demographic Characteristics ◽  
The Internet ◽  
Substantial Impact ◽  
Limited Basis ◽  
K 12 ◽  
The Impact

The divide between those who have computer and Internet access and those who do not appears to be narrowing, however overall statistics may be misleading. Measures of computer availability in schools often include cases where computers are only available for administration or are available only on a very limited basis (Gootman, 2004). Access to a computer and the Internet outside of school helps to reinforce student learning and emphasize the importance of using technology. Recent U.S. statistics indicate that ethnic background and other demographic characteristics still have substantial impact on the availability and use of computers by students outside of the classroom. This paper examines recent census data to determine the impact of the household on student computer use outside of the classroom. Encouragingly, the findings of this study suggest that use of a computer at school substantially increases the chance that a student will use a computer outside of class. Additionally, this study suggests that computer use outside of the classroom is positively and significantly impacted by being in a household with adults who either use a computer at work or work in an industry where computers are extensively used.

Valorization of the Pharmacological Potential of Phytochemical Compounds Contained in the Crude Extract of the Root of a Plant of Withania frutescens L

2019 ◽  
Author(s):  
A. EL Moussaoui ◽  
F. Jawhari ◽  
K. EL Ouahdani ◽  
I. Es-Safi ◽  
D. Bousta ◽  
...  
Keyword(s):  
Crude Extract ◽  
Control Group ◽  
Root Extract ◽  
Nacl Solution ◽  
Phytochemical Compounds ◽  
Anti Inflammatory ◽  
Pharmacological Potential

Our present study focuses on the evaluation of the analgesic, anti-inflammatory and healing activity of Withania frutescens L. The anti-inflammatory result has an inhibition percentage of 78.87% ± 7.08 at 450 mg/kg and 75.14% ± 6.39 at 400 mg/kg and 89.75% ± 3.44 for diclofenac (1%). When applied locally, the 10% cream has an inflammation inhibition of 96.87% ± 5.85 and 76.14% ± 7.88 for the 5% cream with 89.87 ± 6.20 of reference (Indomethacin). The abdominal contractions of rats treated with the root extract are significantly lower than those of the control group that received only physiological NaCl solution, with 41.20 ± 2.30 for the extract and 82.20 ± 5.04 for NaCl and 53.40 ± 4.94 for the reference. The healing activity of the studied extract records a percentage of contraction of about 93.20% ± 3.36 (Extract 10%), 84.50% ± 3.84 (Extract 5%), 48.47% ± 2.15 (control) and 81.88 ± 2.24 for the reference.

Sign in / Sign up

Export Citation Format

Share Document