scholarly journals Inferring microevolution from museum collections and resampling: lessons learned from Cepaea

2016 ◽  
Author(s):  
Małgorzata Ożgo ◽  
Thor-Seng Liew ◽  
Nicole B Webster ◽  
Menno Schilthuizen
Keyword(s):  
Land Snail ◽  
Evolutionary Change ◽  
Lessons Learned ◽  
Evolutionary Trends ◽  
Frequency Distributions ◽  
The Past ◽  
Contemporary Sample ◽  
Evolutionary Response ◽  
Historical Sample

Studies documenting Human-Induced Rapid Evolutionary Change (HIREC) routinely compare contemporary allele or morph frequency distributions with historical baselines. All too often, this involves the re-sampling of a population that was sampled at a single time point in the past. However, year-to-year fluctuations in magnitude and direction of evolutionary response may make such studies prone to erroneous conclusions, where long-term evolutionary trends are inferred from what in fact are short-term fluctuations. Here, we explore this problem by re-sampling three Dutch populations of the land snail Cepaea nemoralis, whose shell colour polymorphism is known to be under thermal and predatory selection. Each of these three populations was originally sampled in at least two different years in the past. We show that conclusions on evolutionary change are strongly dependent on which of the historical sample dates is used for comparison with the contemporary sample. Our study highlights the fact that year-to-year variation in allele frequencies may often be so strong that a simple two-point comparison is unreliable to detect long-term evolutionary trends.

scholarly journals Inferring microevolution from museum collections and resampling: lessons learned from Cepaea

2016 ◽  
Author(s):  
Małgorzata Ożgo ◽  
Thor-Seng Liew ◽  
Nicole B Webster ◽  
Menno Schilthuizen
Keyword(s):  
Land Snail ◽  
Evolutionary Change ◽  
Lessons Learned ◽  
Evolutionary Trends ◽  
Frequency Distributions ◽  
The Past ◽  
Contemporary Sample ◽  
Evolutionary Response ◽  
Historical Sample

Studies documenting Human-Induced Rapid Evolutionary Change (HIREC) routinely compare contemporary allele or morph frequency distributions with historical baselines. All too often, this involves the re-sampling of a population that was sampled at a single time point in the past. However, year-to-year fluctuations in magnitude and direction of evolutionary response may make such studies prone to erroneous conclusions, where long-term evolutionary trends are inferred from what in fact are short-term fluctuations. Here, we explore this problem by re-sampling three Dutch populations of the land snail Cepaea nemoralis, whose shell colour polymorphism is known to be under thermal and predatory selection. Each of these three populations was originally sampled in at least two different years in the past. We show that conclusions on evolutionary change are strongly dependent on which of the historical sample dates is used for comparison with the contemporary sample. Our study highlights the fact that year-to-year variation in allele frequencies may often be so strong that a simple two-point comparison is unreliable to detect long-term evolutionary trends.

Research of the motivation and long-term objectives of Bulgarian and Serbian students

2019 ◽  
Vol 27 (2) ◽  
Author(s):  
Mariana Borukova ◽  
Vladimir Kotev
Keyword(s):  
Comparative Analysis ◽  
Everyday Life ◽  
Educational Development ◽  
Variation Analysis ◽  
Frequency Distributions ◽  
The Past ◽  
The Everyday ◽  
The University ◽  
Personal Assessment

Education is an activity requiring lengthy efforts and perseverance, as well as skills for acquiring information and its creative usage. All this is based on prolonged motivation, directly related to the improvement of the educational development and the consecutive professional realization. Long-term objectives serve as coordinating terms leading to particular goals in the everyday life and thus, behaviour could be rationalized and directed in a longer prospective towards both the past and the future. The aim of the present study is to survey the opinion and personal assessment of the long-term motivation of students from NSA “Vassil Levski”, Sofia and students from Nish, Serbia. The research was conducted from November 2016 to May 2017. It was done among 96 students (45 fourth-year students at NSA and 51 students from the University in Nish). The students had to fill out a test consisting of 10 questions related to their personal assessment of their long-term motivation. The results of the study were processed mathematically and statistically by: variation analysis, relative share, comparative analysis of two independent samples and comparative analysis of the frequency distributions with χ² – the Pearson criterion.According to the generalized conclusions, a higher percentage of the Bulgarian students is directed towards long-term objectives and prospects than the percentage of the Serbian students. Women are more motivated in their long-term development than men but there are not statistically significant differences along all the questions. Athletes’ motivation is higher than the average one for the whole population. We believe, however, that the motivation changes in the course of the studies and we assume it is higher for the students who are about to graduate.

scholarly journals Lessons Learned from the Hubble Space Telescope (HST) Contamination Control Program

2007 ◽  
Vol 50 (1) ◽  
pp. 44-60
Author(s):  
Patricia Hansen ◽  
Jacqueline Townsend ◽  
Randy Hedgeland
Keyword(s):  
Hubble Space Telescope ◽  
Control Program ◽  
Scientific Data ◽  
Lessons Learned ◽  
Space Telescope ◽  
Contamination Control ◽  
The Past ◽  
Integration Program ◽  
New Generation

Over the past two decades, the Hubble Space Telescope (HST) contamination control program has evolved from a ground-based integration program to a space-based science-sustaining program. The contamination controls from new-generation scientific instruments and orbital replacement units were incorporated into the HST contamination control program to maintain scientific capability over the life of the telescope. Long-term, on-orbit scientific data have shown that the contamination controls implemented for the instruments, servicing mission activities (Orbiter, astronauts, and mission), and on-orbit operations successfully protected the HST from contamination and the instruments from self-contamination.

scholarly journals An Era of Appropriate Technology: Evolutions, Oversights and Opportunities

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Jessie Lissenden ◽  
Siri Maley ◽  
Khanjan Mehta
Keyword(s):  
Implementation Strategy ◽  
Large Scale ◽  
Knowledge Exchange ◽  
Lessons Learned ◽  
Appropriate Technology ◽  
Practical Application ◽  
Academic Literature ◽  
The Past ◽  
Project Lifecycle

As we develop practical, innovative and sustainable technology solutions for resource-constrained settings, what can we learn from the Appropriate Technology (AT) movement? Based on a review of academic literature over the past 35 years, this article identifies, and chronologically maps, the defining tenets and metrics of success advocated by scholars. The literature has gradually evolved from general musings into concrete lessons learned, while the definitions of “success” have transitioned from laboratory success into practical application and long-term usefulness. Nonetheless, juxtaposing this scholastic history with actual projects reveals three major gaps in AT philosophy related to a lack of 1) bilateral knowledge exchange, 2) emphasis on venture scalability, and 3) integration of implementation strategy through the project lifecycle. This article argues that rethinking and repositioning AT with a human-centric narrative emphasizing sustainability and scalability is imperative in order to revitalize and accelerate the AT movement and to achieve the large-scale impact it was expected to deliver.

scholarly journals Inferring microevolution from museum collections and resampling: lessons learned from Cepaea

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3938 ◽  
Author(s):  
Małgorzata Ożgo ◽  
Thor-Seng Liew ◽  
Nicole B. Webster ◽  
Menno Schilthuizen
Keyword(s):  
Natural History ◽  
Common Species ◽  
Land Snail ◽  
Lessons Learned ◽  
General Direction ◽  
Cepaea Nemoralis ◽  
Natural History Collections ◽  
Evolutionary Changes ◽  
Long Term Trends

Natural history collections are an important and largely untapped source of long-term data on evolutionary changes in wild populations. Here, we utilize three large geo-referenced sets of samples of the common European land-snail Cepaea nemoralis stored in the collection of Naturalis Biodiversity Center in Leiden, the Netherlands. Resampling of these populations allowed us to gain insight into changes occurring over 95, 69, and 50 years. Cepaea nemoralis is polymorphic for the colour and banding of the shell; the mode of inheritance of these patterns is known, and the polymorphism is under both thermal and predatory selection. At two sites the general direction of changes was towards lighter shells (yellow and less heavily banded), which is consistent with predictions based on on-going climatic change. At one site no directional changes were detected. At all sites there were significant shifts in morph frequencies between years, and our study contributes to the recognition that short-term changes in the states of populations often exceed long-term trends. Our interpretation was limited by the few time points available in the studied collections. We therefore stress the need for natural history collections to routinely collect large samples of common species, to allow much more reliable hind-casting of evolutionary responses to environmental change.

Quantifying Seafood Through Time: Counting Calories in the Fossil Record

2013 ◽  
Vol 19 ◽  
pp. 21-50 ◽  
Author(s):  
Seth Finnegan
Keyword(s):  
Benthic Invertebrates ◽  
Fossil Record ◽  
Ecosystem Structure ◽  
Evolutionary Trends ◽  
Earth Systems ◽  
The Past ◽  
Different Types ◽  
Lines Of Evidence ◽  
Accurate Quantification

Energy and nutrients are the fundamental currencies of ecology and changes in energy and nutrient availability are thought to have played an important role in the long-term development of marine ecosystems. However, meaningfully quantifying when, where, and how such changes have occurred has been a difficult and longstanding problem. Here, some of the various lines of evidence that have been brought to bear on this issue in the past two decades are reviewed, particularly those based on the fossil record of benthic invertebrates. This paper focuses on abundance, body size, and metabolism, three distinct but closely interrelated aspects of ecosystem structure that control (or are controlled by) energy fluxes. Each of these is subject to biases and inherent uncertainties that present significant challenges for making inferences from the fossil record, but when carefully controlling for environmental, taphonomic, and methodological variations there are robust trends that can be discerned above the noise. Integrating these different types of data in a single quantitative framework presents additional complications, but coherent patterns emerge from some such analyses. Accurate quantification of energetic trends in the fossil record is difficult but is a worthwhile goal because of its potential to illuminate the energetic dimension of major diversifications, extinctions, and secular ecological-evolutionary trends and link them more directly to their Earth Systems context.

scholarly journals Launching Hong Kong’s Healthcare Financing Reform: why continued inaction? 87

2016 ◽  
Vol 11 (3) ◽  
pp. 87-102
Author(s):  
Geoffrey Lieu
Keyword(s):  
Lessons Learned ◽  
Financial Sustainability ◽  
Healthcare Financing ◽  
Reform Initiatives ◽  
Reform Agenda ◽  
The Past ◽  
Conflicting Interests ◽  
The Right ◽  
Public Consultations

Hong Kong has sought without progress in the past 25 years to introduce reform proposals to enhance the long-term financial sustainability of its healthcare system. Through a systematic review of the consultation documents released over the years, this paper examines what might have been done right or wrong and pinpoints lessons learned for healthcare leaders, executives and reformers facing looming opportunities for reform. The findings suggest that the phased-approach of introducing reform options, involving step-by-step public consultations, to engaging the community to give their views on the healthcare financing reform options has not been effective. Other factors, including changes in the stewardship of the reform initiatives and the top-down elitist-led preparations of pre-launch work, added to the resultant inaction of not taking any of the reform proposals forward for launch and to produce reform. The study proposes that a broadly participatory approach, involving a wider base of members of the community in an inclusive guiding coalition charged to drive the reform from prelaunch to implementation, be undertaken. This coalition should start afresh and, based on renewed evidencebased assessments of the need and urgency of reform, proceed accordingly to formulate, if indicated, an overarching healthcare financing reform agenda that motivates people with conflicting interests to take mutually beneficial actions or that gives stakeholders the right incentives to work effectively together.

scholarly journals Non-stationarity driven by long-term change in catchment storage: possibilities and implications

2015 ◽  
Vol 371 ◽  
pp. 7-12 ◽  
Author(s):  
J. D. Hughes ◽  
J. Vaze
Keyword(s):  
Predictive Performance ◽  
Lessons Learned ◽  
Significant Shift ◽  
Model Structure ◽  
Generation Process ◽  
Rainfall Runoff ◽  
Runoff Generation ◽  
The Past ◽  
Term Change

Abstract. "Non-stationarity" with reference to hydrology is a term applied to many situations (Milly et al., 2008). While climate change non-stationarity is often examined, these effects can provide a test for assumptions of runoff generation process impliedin rainfall–runoff (RR) models. Observations from South-western Australia (SWA) over the past 40 years show a decline in rainfall and reductions in runoff. Runoff and rainfall relationships in SWA show a significant shift over the past 40 years suggesting a change in runoff generation and catchment state. This has challenged the nature of assumed runoff generation process in SWA as well as the veracity of conceptual RR model structure. We expand on some of the lessons learned from SWA and discuss the climatic and geomorphic conditions that may make reasonable predictions of runoff very difficult with RR models calibrated in traditional ways. Catchment storage has a significant interaction with runoff generation and we examine the situations where these may change in the longer term. We suggest some strategies in terms of model structure and calibration that may improve predictive performance in such situations.

scholarly journals Long-term culture at elevated atmospheric CO 2 fails to evoke specific adaptation in seven freshwater phytoplankton species

2013 ◽  
Vol 280 (1754) ◽  
pp. 20122598 ◽  
Author(s):  
Etienne Low-Décarie ◽  
Mark D. Jewell ◽  
Gregor F. Fussmann ◽  
Graham Bell
Keyword(s):  
Liquid Medium ◽  
Evolutionary Change ◽  
Carbon Utilization ◽  
Specific Adaptation ◽  
Freshwater Phytoplankton ◽  
Photosynthetic Organisms ◽  
Solid Agar ◽  
Evolutionary Response ◽  
Phytoplankton Communities

The concentration of CO 2 in the atmosphere is expected to double by the end of the century. Experiments have shown that this will have important effects on the physiology and ecology of photosynthetic organisms, but it is still unclear if elevated CO 2 will elicit an evolutionary response in primary producers that causes changes in physiological and ecological attributes. In this study, we cultured lines of seven species of freshwater phytoplankton from three major groups at current (approx. 380 ppm CO 2 ) and predicted future conditions (1000 ppm CO 2 ) for over 750 generations. We grew the phytoplankton under three culture regimes: nutrient-replete liquid medium, nutrient-poor liquid medium and solid agar medium. We then performed reciprocal transplant assays to test for specific adaptation to elevated CO 2 in these lines. We found no evidence for evolutionary change. We conclude that the physiology of carbon utilization may be conserved in natural freshwater phytoplankton communities experiencing rising atmospheric CO 2 levels, without substantial evolutionary change.

Maximizing Outcomes in Group Treatment of Aphasia: Lessons Learned From a Community-Based Center

2014 ◽  
Vol 24 (3) ◽  
pp. 100-105 ◽  
Author(s):  
Darlene Williamson
Keyword(s):  
Group Treatment ◽  
Treatment Protocol ◽  
Lessons Learned ◽  
Group Program ◽  
Community Based ◽  
Multiple Treatment ◽  
Use Of Technology ◽  
Communication Impairments ◽  
Treatment Settings

Given the potential of long term intervention to positively influence speech/language and psychosocial domains, a treatment protocol was developed at the Stroke Comeback Center which addresses communication impairments arising from chronic aphasia. This article presents the details of this program including the group purposes and principles, the use of technology in groups, and the applicability of a group program across multiple treatment settings.

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