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Introduction of Exotic Species

admin — Tue, 21 Jul 2009 10:51:38 +0000

This is an environmental issue that emerged in the 1990s, though the reasons for it go back much further. For example, the building of the Suez Canal has resulted in the movement of many species from the Red Sea into the eastern Mediterranean, some of which, like large sharks, are not popular newcomers. Another route is the expansion of shellfish culture, especially of oysters, in which the local stocks have been ‘improved’ by the introduction of larger, faster-growing species from far afield, often bringing with them pests and diseases that have subsequently run rampant. The growing popularity of keeping marine species in aquaria has also resulted in the importation of undesirable new species, the most notorious of these being the appearance of a vigorous spore of a highly invasive green seaweed, Caulerpa, beneath the windows of the marine aquarium in Monaco. This male spore can only reproduce by fragments of it being carried around by ships. However, once established it overgrows the local seaweed communities, drastically reducing the diversity, and destroying local fisheries. Not being able to breed sexually has been no bar to its dispersal; in two decades it has become established all round the western Mediterranean and is now in the eastern Mediterranean, most probably carried on the anchors of pleasure craft. Even more surprising has been its recent appearance in the seas off Japan, Australia, and California, in each case probably as a result of establishing marine aquaria.

Future Challenges

admin — Mon, 16 Feb 2009 14:44:13 +0000

Motivation is a rich and changing field that has enjoyed much progress in its relatively brief history. In more than six decades following Hull’s insights, there have been major upheavals in the field (the shift from behaviorism to cognition); new theories and concepts have been introduced, and novel research directions have been pursued (such as the finding that reward can decrease motivation). Principles of motivation have been described that can become the basis for intervention. Quite a bit is known, for example, about the positive motivational consequences of attributing failure to lack of effort rather than low ability, of selecting tasks of intermediate difficulty, and of focusing on mastery rather than outperforming others. All these principles have good theoretical and empirical grounding. The challenge for the future will be to study motivation in context. Examining achievement expectancy, values, and goals and how they get expressed in the broader context of social and cultural influences might provide important clues for understanding the academic challenges faced by many ethnic minority youth. Addressing such issues will be a useful step toward promoting the field of motivation in education research and assuring its continued vitality.

Achievement Goals

admin — Sun, 04 Jan 2009 14:24:22 +0000

Achievement goals capture the reasons why a person engages in achievement behavior, and two broad types have been identified. Students who pursue mastery goals are oriented toward acquiring new skills or improving their level of competence. In contrast, students who adopt performance goals are motivated by the intent to demonstrate that they have adequate ability and avoid displaying signs that they have low ability. According to this analysis, individuals can therefore decide to engage in achievement activities for two very different reasons: They may strive to develop competence by learning as much as they can, or they may strive to publicly display their competence by trying to outperform others.