scholarly journals Nectar bacteria, but not yeast, weaken a plant–pollinator mutualism

2013 ◽  
Vol 280 (1752) ◽  
pp. 20122601 ◽  
Author(s):  
Rachel L. Vannette ◽  
Marie-Pierre L. Gauthier ◽  
Tadashi Fukami

Mutualistic interactions are often subject to exploitation by species that are not directly involved in the mutualism. Understanding which organisms act as such ‘third-party’ species and how they do so is a major challenge in the current study of mutualistic interactions. Here, we show that even species that appear ecologically similar can have contrasting effects as third-party species. We experimentally compared the effects of nectar-inhabiting bacteria and yeasts on the strength of a mutualism between a hummingbird-pollinated shrub, Mimulus aurantiacus , and its pollinators. We found that the common bacterium Gluconobacter sp., but not the common yeast Metschnikowia reukaufii , reduced pollination success, seed set and nectar consumption by pollinators, thereby weakening the plant–pollinator mutualism. We also found that the bacteria reduced nectar pH and total sugar concentration more greatly than the yeasts did and that the bacteria decreased glucose concentration and increased fructose concentration whereas the yeasts affected neither. These distinct changes to nectar chemistry may underlie the microbes' contrasting effects on the mutualism. Our results suggest that it is necessary to understand the determinants of microbial species composition in nectar and their differential modification of floral rewards to explain the mutual benefits that plants and pollinators gain from each other.

2019 ◽  
Author(s):  
Ignacio Cofone ◽  
Adriana Robertson

Privacy loss is central to privacy law scholarship, but a clear definition of the concept remains elusive. We present a model that both captures the essence of privacy loss and can be easily applied to policy evaluations and doctrinal debates. To do so, we use standard Bayesian statistics to formalize a key intuition: that information privacy is fundamentally linked to how much other people know about you. A key advantage of our model is that, for the first time, it takes privacy preferences seriously while maintaining tractability. Another key advantage is that, by viewing privacy as a continuum, it is more realistic and is better suited for evaluating “gray areas” than prior models.We apply this framework to two central areas of privacy law: the common law privacy tort and the Fourth Amendment’s third-party doctrine. In the tort context, we first show how our proposal helps to clarify current law, and then use it to distinguish between the two interests protected by the privacy tort: privacy interests and reputational interests. We then propose a simple framework for judges to use in providing remedies for both classes of claims. We then move on to the third party doctrine. We show that many of the shortcomings associated with the doctrine stem from the misguided assumption that privacy is dichotomous rather than a spectrum, as in our model. We then liken this to the standard of care familiar from tort law, and show how the current doctrine results in the equivalent of a strict liability standard, rather than a more appropriate negligence-based standard.


Author(s):  
C. Daniel Batson

Despite its virtues, empathy-induced altruism can at times harm those in need, other people, and the altruistically motivated person. Specifically, it can hurt those in need when acted on without wisdom and sensitivity or when a cool head is required. It can produce paternalism. It is less likely to be evoked by nonpersonalized, abstract, chronic needs. It can be a source of immoral action, leading us to show partiality toward those for whom we feel empathic concern even when we know that to do so is neither fair nor best for all. Indeed, when our behavior is public, empathy-induced altruism can pose a more serious threat to the common good than does self-interest. Finally, it can at times jeopardize our mental and physical health—even our life. Any attempt to call on empathy-induced altruism to build a more humane society needs to take these problems into account lest we do more harm than good.


Author(s):  
Yannis Theocharis ◽  
Joost de Moor

Creative participation refers to citizens’ invention of, and engagement in, new action forms that aim to influence, or take responsibility for, the common good in society. By definition, these action forms are constantly evolving and cannot be listed or summarized. Yet some, like guerrilla gardening, have over time become more established in political repertoires, and specific arenas are known to be particularly productive sites for their development. These include in particular the Internet, and lifestyles and consumption. The constant changes in how citizens become active represented by creative participation present considerable challenges for scholars of political participation—both in terms of theory and methodology. In particular, such forms test our ability to distinguish political from nonpolitical activities. However, how political creative participation is, is often subtle and implicit, and therefore hard to establish. Yet being able to do so is essential for an ongoing assessment of the quality of participatory democracy. With conventional forms of participation declining and creative participation becoming more common, scholars must be able to agree on definitions and operationalizations that allow for the comparison of participatory trends. For instance, a key concern has been whether creative forms of participation crowd out more conventional ones, like voting or lobbying politicians. Developments in survey research have been able to show that this is not the case and that creative participation may in fact increase conventional participation. In addition, qualitative research methods like focus groups and ethnography, allow for more open-ended explorations of this elusive research topic. As to who participates, creative participation has enabled traditionally underrepresented groups like women and young people to catch up with, and sometimes overtake, those older men who have long dominated conventional political participation. Still, education remains a key obstacle even to creative participation. The COVID-19 crisis that took hold of the world in 2020 has compromised access to collective action and public space. It has thereby once more put the onus on citizens to engage creatively with ways to influence, and take responsibility for, society. At the same time, the crisis presents a need and opportunity for political participation scholarship to engage more deeply with theoretical debates about what it means to be political or to participate.


1998 ◽  
Vol 37 (04/05) ◽  
pp. 394-403 ◽  
Author(s):  
J. J. Cimino

AbstractBuilders of medical informatics applications need controlled medical vocabularies to support their applications and it is to their advantage to use available standards. In order to do so, however, these standards need to address the requirements of their intended users. Overthe past decade, medical informatics researchers have begun to articulate some of these requirements. This paper brings together some of the common themes which have been described, including: vocabulary content, concept orientation, concept permanence, nonsemantic concept identifiers, polyhierarchy, formal definitions, rejection of “not elsewhere classified” terms, multiple granularities, mUltiple consistent views, context representation, graceful evolution, and recognized redundancy. Standards developers are beginning to recognize and address these desiderata and adapt their offerings to meet them.


Botany ◽  
2010 ◽  
Vol 88 (3) ◽  
pp. 241-249 ◽  
Author(s):  
Diana Bizecki Robson

Flower-visiting insect activity to the rare Symphyotrichum sericeum (Vent.) G.L. Nesom and the common Solidago nemoralis Ait. var. longipetiolata (Mack. & Bush) Pal. & Steyerm. was examined to detect compositional and temporal similarities. A hand pollination experiment was conducted to determine whether pollen was limiting seed set. Of the 31 insect taxa that visited these plants, Bombus bifarius Cresson was the most common visitor to both species. More insect visitors of the Halictidae and Bombyliidae were received by S. sericeum than S. nemoralis, which received more visitors of the Syrphidae and Tachinidae. The insect visitation rate was not significantly different between the two plant species. Solidago nemoralis was visited by fewer insect taxa per day than S. sericeum, but the constancy of its visitors was higher. The insect visitor composition changed over time, with B. bifarius ignoring S. sericeum plants initially, then visiting them more frequently as the number of receptive S. nemoralis capitula declined. Hand pollination increased seed set in the earliest flowering capitula of S. sericeum, but not for those flowering during the peak. This research shows that the quantity of insect visits to the rare plant is comparable with that of the common plant but that pollination quality may be lower, particularly for early blooming capitula.


2019 ◽  
Author(s):  
Philip Garboden

The majority of rental properties in the U.S. today is owned by small- to medium-sized investors, many of whom enter the trade with little prior experience. This paper considers the cultural factors that motivate these amateurs to purchase real estate–an investment with high risks and relatively poor returns. Drawing on in-depth interviews with 93 investors in three heterogeneous real estate markets, Baltimore, MD, Dallas, TX, and Cleveland, OH, combined with participant observation of 22 real estate investment association meetings (REIAs), this paper finds that amateurs who decide to become investors often do so during periods when their professional identities are insecure or they perceive their retirement portfolios to be insufficient. Through participation in real estate investment associations and other investor networks, they quickly internalize “investor culture,” embracing ideologies of self-sufficiency and risk. “Investor culture”—perpetuated by REIAs--motivates and legitimizes strategies of action that lead to increasingly leveraged investments. Third-party actors, including real estate gurus, paid mentors, and private “hard money” lenders exploit the intersection of insecurity and the propagation of investor culture to profit off amateurs’ investment decisions.


Web Ecology ◽  
2018 ◽  
Vol 18 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Manuela Giovanetti ◽  
Margarida Ramos ◽  
Cristina Máguas

Abstract. Acacia longifolia, a native legume from Australia, has been introduced in many European countries and elsewhere, thus becoming one of the most important global invasive species. In Europe, its flowering occurs in a period unsuitable for insect activity: nonetheless it is considered entomophilous. Floral traits of this species are puzzling: brightly coloured and scented as liked by insects, but with abundant staminate small-sized flowers and relatively small pollen grains, as it is common in anemophilous species. Invasion processes are especially favoured when reshaping local ecological networks, thus the interest in understanding pollination syndromes associated with invasive plant species that may facilitate invasiveness. Moreover, a striking difference exists between its massive flowering and relatively poor seed set. We introduced a novel approach: first, we consider the possibility that a part of the pollination success is carried on by wind and, second, we weighted the ethological perspective of the main pollinator. During the flowering season of A. longifolia (February–April 2016), we carried on exclusion experiments to detect the relative contribution of insects and wind. While the exclusion experiments corroborated the need for pollen vectors, we actually recorded a low abundance of insects. The honeybee, known pollinator of acacias, was relatively rare and not always productive in terms of successful visits. While wind contributed to seed set, focal observations confirmed that honeybees transfer pollen when visiting both the inflorescences to collect pollen and the extrafloral nectaries to collect nectar. The mixed pollination strategy of A. longifolia may then be the basis of its success in invading Portugal's windy coasts.


2017 ◽  
Vol 3 (1) ◽  
pp. 43
Author(s):  
Zuzanna Służewska

THE CONTRACT OF PARTNERSHIP AS A BASE OF IN SOLIDUM LIABILITY IN ROMAN LAWSummary In the modern civil law joint and several liability of partners in a partnership is a rule rather than an exception. According to the common opinion this concept did not originate in the Roman law but was first invented in the medieval times by glossators and commentators. The Roman partnership created only a private relation between partners (who, due to a conclusion of that contract were reciprocally obliged to act together in accordance with a good faith in order to conduct common business and to divide profits and bear losses in proportion to their respective shares) and its conclusion did not affect their liability against third parties. The partners had no right to bind themselves contractually to any third parties, unless they all acted jointly (in this case, however, their joint representation was derived from their expressed declarations and not the existence of a contract o f partnership). Thus, any commitment made by an individual partner, even if made within the scope of a partnership having obtained other partners’ consent, was treated as a personal debt of this partner and the remaining partners were not liable against his contractor. Then, of course, the partner who made a commitment (acting within the partnership’s business) could claim a part of what he had paid to a third party from other partners in proportion to their respective shares in the common enterprise.Such a solution was necessary because of the purely consensual character o f the Roman partnership and the lack of any formal procedure of its conclusion and dissolution. The existence of that contract could not affect the model of the external liability of partners, because it would be too risky for third parties, which had no possibility to make sure if a contract of partnership between some persons had been actually concluded or not. Thus, the role of a contract of partnership in the Roman law was only limited to determine a mutual liability o f partners, to specify their respective rights and obligations and to define the scope of their liability against other partners.There are only a few written sources concerning so called specific kinds of partnership characterized by untypical joint and several responsibility of partners. Moreover these texts are not very clear and are difficult to interpret, so the issue of specific kinds of a partnership is a matter of doubts among Romanists. Some authors even believe that the specific types of partnership did not exist in the Roman law at all.It should be firstly observed that the texts regarding a contract of partnership itself (the texts included in the title pro socio of Justinian’ Digest) did not raise the question of the external liability of partners because they were devoted to internal settlement o f accounts within sociu Thus, taking into account only these texts one cannot ascertain that a conclusion of a contract of partnership could not affect in any way the model of the partners’ liability against third parties.Secondly, the other texts concerning the regulation of conducting an economic activity in the Roman law (actio institoria, actio exercitoria and actio de peculio) present some regularity in an introduction of joint and several liability of debtors.On the one hand that model of the liability was introduced in situations in which protecting safety of trade required that the creditor be able to claim a whole amount o f the debt from one person only.On the other hand this model of liability could be introduced only in these cases in which some internal relation existed between several debtors. On the grounds of such relations the debtor who satisfied in full the creditor’s claim could sue other debtors in order to recover their respective parts in the debt. In the Roman law that internal relation that guaranteed the possibility of a recourse could be either a joint-ownership or a partnership.Having considered that, one may say that the texts concerning specific kinds o f partnership do not prove existence of any special type of societas. These sources regard only the situations when a joint and several liability between several debtors was introduced because it was justified by the circumstances: that is the necessity to protect the safety of trade on one hand and the existence of the contract of partnership that guaranteed a possibility to realize the recourse, on the other.In conclusion one may say that although a closing of a contract of partnership did not create a joint and several liability of partners, in some cases its existence was decisive for introducing this model of liability since it guaranteed to every party a possibility to act against the others to obtain the recourse. Thus, Roman jurisprudence made an important step towards the future introduction o f joint and several liability of partners as a rule of a civil law.


Sign in / Sign up

Export Citation Format

Share Document