Color choices by bumble bees (Bombus terrestris): innate preferences and generalization after learning

It is usually assumed that the choice behavior of bees for floral colors is influenced by innate preferences only for the first flower visits prior to any experience. After visits to rewarding flowers bees learn to associate their colors with a reward. This learning process leads to an acquired preference for the trained colors that has been believed to dominate over previous experiences and over innate preferences. This work investigates how bumble bees (Bombus terrestris) chose among artificial flowers of different colors after they had been extensively trained to other colors. The bees chose novel colors according to their similarity to the trained color if the trained color was similar to some of the test colors. This was true also if trained colors and test colors were well distinguished, so their color choice reflected generalization between colors. If the test colors were so different from the trained color that no generalization took place, choice behavior was not affected by the trained color and reflected innate preferences. The differences in choice frequencies could not be explained by physical properties of the test colors other than the dominant wavelength, a parameter taken to reflect hue perception. Preferred dominant wavelengths correspond to those observed in naive bumble bees and honeybees. Thus bumble bees show innate preferences for certain colors not only prior to color learning but also after intensive learning when choosing among very different novel colors. Color choice among similar colors, however, is controlled by generalization from the learned color. Received: 9 November 1999 / Received in revised form: 19 March 2000 / Accepted: 31 March 2000     

The effect of larval and early adult experience on behavioural plasticity of the aphid parasitoid <Emphasis Type="Italic">Aphidius ervi</Emphasis> (Hymenoptera,Braconidae, Aphidiinae)

The relevance of the integration of preimaginal and eclosion experiences on the subsequent habitat preferences and mate finding by the adult has been rarely tested in holometabolous insects. In this work, the effect of larval and early adult experiences on the behavioural responses of adult males of the aphid parasitoid, Aphidius ervi, towards volatiles from the host–plant complex (HPC) and from conspecific females were evaluated. Two experience factors were considered: host diet (normal diet=ND; artificial diet=AD), and eclosion, i.e. extraction or non-extraction of the parasitoid larva from the parasitised aphid (extracted=EX; non-extracted=NE). Thus, four treatments were set up: ND/NE, ND/EX, AD/NE and AD/EX. Glass Y-tube olfactometers were used to investigate the responses of adult A. ervi males to the odour sources used. Males from the ND/NE treatment showed a shorter latency to the first choice of olfactometer arms, displayed a marked preference towards the HPC olfactometer arm, and spent more time in the HPC arm than males from the other treatments. Only the interaction of host diet and eclosion experiences proved to be relevant in explaining the differences in latency to first choice, time spent in olfactometers arms, and behaviours displayed in the olfactometer arms. These results show the importance of the integration of larval and eclosion experiences in the development of stereotyped responses of the adults. This process may involve memory retention from the preimaginal and emergence period, but further research is needed to disentangle the contribution of each stage. The response to conspecific females was much less affected by the treatments in relation to first arm choice and times in olfactometer arms, suggesting a pheromone-mediated behaviour, even though a prompter and more intense wing fanning courtship behaviour was registered in the ND/NE males compared to males from the AD/NE treatment. These results show that sexual behaviours are less affected by early experiences than behaviours related with finding a HPC for foraging or oviposition. Taken together, our results demonstrate for first time that larval and eclosion experiences affect in a differential way the early responses of the adult towards environment-derived cues and mate related cues.     

Accelerating Adaptation of Natural Resource Management to Address Climate Change

Natural resource managers are seeking tools to help them address current and future effects of climate change. We present a model for collaborative planning aimed at identifying ways to adapt management actions to address the effects of climate change in landscapes that cross public and private jurisdictional boundaries. The Southwest Climate Change Initiative (SWCCI) piloted the Adaptation for Conservation Targets (ACT) planning approach at workshops in 4 southwestern U.S. landscapes. This planning approach successfully increased participants’ self‐reported capacity to address climate change by providing them with a better understanding of potential effects and guiding the identification of solutions. The workshops fostered cross‐jurisdictional and multidisciplinary dialogue on climate change through active participation of scientists and managers in assessing climate change effects, discussing the implications of those effects for determining management goals and activities, and cultivating opportunities for regional coordination on adaptation of management plans. Facilitated application of the ACT framework advanced group discussions beyond assessing effects to devising options to mitigate the effects of climate change on specific species, ecological functions, and ecosystems. Participants addressed uncertainty about future conditions by considering more than one climate‐change scenario. They outlined opportunities and identified next steps for implementing several actions, and local partnerships have begun implementing actions and conducting additional planning. Continued investment in adaptation of management plans and actions to address the effects of climate change in the southwestern United States and extension of the approaches used in this project to additional landscapes are needed if biological diversity and ecosystem services are to be maintained in a rapidly changing world. Acelerando la Adaptación del Manejo de Recursos Naturales para Atender el Cambio Climático     

开源与教育

开源教育对于学校和学生均具有明显的获益。我国开源教育发展了数年时间，政府和众多开源企业也一直在摸索一条适合我国开源教育的道路，但整体看来，发展较慢。本文分析了开源在我国的发展情况，结合高等教育，通过与国外发展的对比，指出了开源在我国、在教育领域发展缓慢的主要因素，并就此提出了建议措施。     

Assessing the role of learning devices and geovisualisation tools for collective action in natural resource management: Experiences from Vietnam

In northern Vietnam uplands the successive policy reforms that accompanied agricultural decollectivisation triggered very rapid changes in land use in the 1990s. From a centralized system of natural resource management, a multitude of individual strategies emerged which contributed to new production interactions among farming households, changes in landscape structures, and conflicting strategies among local stakeholders. Within this context of agrarian transition, learning devices can help local communities to collectively design their own course of action towards sustainable natural resource management. This paper presents a collaborative approach combining a number of participatory methods and geovisualisation tools (e.g., spatially explicit multi-agent models and role-playing games) with the shared goal to analyse and represent the interactions between: (i) decision-making processes by individual farmers based on the resource profiles of their farms; (ii) the institutions which regulate resource access and usage; and (iii) the biophysical and socioeconomic environment. This methodological pathway is illustrated by a case study in Bac Kan Province where it successfully led to a communication platform on natural resource management. In a context of rapid socioeconomic changes, learning devices and geovisualisation tools helped embed the participatory approach within a process of community development. The combination of different tools, each with its own advantages and constraints, proved highly relevant for supporting collective natural resource management.     

The network imaginary: coherence and creativity within a multiscalar collaborative effort to reform US fire management

In response to the ongoing crisis in fire management, the US Fire Learning Network (FLN) engages partners in collaborative, landscape-scale ecological fire restoration. The paper contends that the FLN employs technologies, planning guidelines and media to articulate an FLN imaginary that co-ordinates independent efforts to engage in ecological fire restoration work without need of either hierarchal authority or collective social capital. This imaginary may allow the FLN to draw on the creativity and adaptive innovation of collaboration to reform fire management institutions and fire-adapted ecosystems.     

The greening of Chicago: environmental leaders and organisational learning in the transition toward a sustainable metropolitan region

Urban sustainability literature calls for new governance relations to support green urban agendas. Privileging non-hierarchical relations, this literature fails to address the means by which organisations create these capacities. The author interviewed public, private and community environmental leaders in metropolitan Chicago regarding their disposition toward creating boundary spanning organisations (BSOs) in addressing the City's Environmental Action Agenda. Their responses reflect engaged efforts to enhance cross-boundary sharing of information, resources, and power. However, they also reflect the decisive role of central authority in initiating this process. These findings suggest the complexity of urban governance in transitions toward sustainability and the opportunities they provide to explore the implications of on-the-ground practice.     

Requisite Simplicities to Help Negotiate Complex Problems

Decision makers responsible for natural resource management often complain that science delivers fragmented information that is not useful at the scale of implementation. We offer a way of negotiating complex problems by putting forward a requisite simplicity. A requisite simplicity attempts to discard some detail, while retaining conceptual clarity and scientific rigor, and helps us move to a new position where we can benefit from new knowledge. We illustrate the above using three case studies: elephant densities and vegetation change in a national park, the use of rules of thumb to support decision making in agriculture, and the management of salt in irrigation. We identify potential requisite simplicities that can allow us to generate new understanding, lead to action and provide opportunities for structured learning.     

Sexual selection in the zebra finch Taeniopygia guttata : condition, sex traits and immune capacity

The aim of this study was to test two hypotheses: (1) that condition-dependent secondary sexual traits reflect an individual's immune capacity and (2) that immune capacity and secondary sexual traits covary with primary sex traits, specifically ejaculate quality. We used the zebra finch Taeniopygia guttata as a study species, since the traits that females find attractive in males of this species, song rate and beak colour, are well established. A paired experimental design comprising 31 pairs of brothers was used; for each pair, one male was assigned to a control group provided with ad libitum food and no additional exercise, and the other male was assigned to an experimental group which experienced additional exercise and a reduced rate of food intake. After 11 weeks, the experimental group differed significantly from the control group in a range of variables, including body mass, haematocrit, granulocyte:lymphocyte (G:L) ratio and several primary sex traits, indicating that condition in this group was reduced. Birds in the experimental group showed a differential response to the treatment. We used the rank order in which birds could be captured by an experimenter as an index of condition. Birds easily caught were assumed to be in poorer condition than those which were more difficult to capture. Rank capture order was repeatable and was significantly correlated with the G:L ratio in the experimental group, but not in the control group. In the experimental group, rank capture order was correlated significantly with both secondary sex traits: birds in better condition had redder beaks and a higher song rate. However, beak colour and song rate did not covary significantly, suggesting that these two traits provide different types of information. Secondary sex traits did not covary with primary sex traits or any sperm features. Thus, there was no evidence for Trivers' sexual-competence hypothesis or the phenotype-linked fertility hypothesis. We used four assays of immune capacity, two general (G:L ratio and spleen mass) and two specific [antibody titres to sheep red blood cells (SRBCs) and Brucella abortus (BA)]. The G:L ratio was significantly higher in the experimental group, spleen mass (absolute and relative) did not differ between the groups, anti-SRBC antibody titres were significantly higher in the control group (contrary to expectation), and anti-BA antibody titres were close to being significantly lower in the experimental group. Within the experimental group, there was no evidence that antibody titres covaried with secondary sex traits. Although we demonstrated that beak colour and song rate were condition dependent, our experiment provided no evidence that either of these traits covaried with immune capacity or sperm features. Received: 9 February 1998 / Accepted after revision: 5 September 1998     

环境类高职院校工学结合人才培养模式构建

立足当前环境类高等职业教育人才培养中存在的突出问题,以＂以人为本＂、＂需求导向＂、＂特色品牌＂、＂工学结合＂为原则,提出了环境类高职院校应在构建人才培养＂三个平台、四个模块＂的基础上,突出实践能力培养,实施工学结合的人才培养模式。