To investigate the evolution of background matching (crypsis) when prey are viewed against uniform and heterogeneous (alternating) backgrounds, we conducted some web-based experiments. Visitors to our experimental web site were rewarded for finding artificial prey, thereby providing a measure of their detectability. We first compared the ''survivorship'' of a range of pixilated prey phenotypes presented against both light green and dark green pixilated backgrounds and found clear evidence for a concave tradeoff curve, indicating that specialism on one or the other background would maximise their overall survivorship. We then compared the survivorship of a range of spotted prey phenotypes presented against backgrounds with small spots and large spots and found evidence for a more linear tradeoff curve, indicating that both intermediates and specialists would have approximately equal survivorship. Replicated evolutionary experiments were then conducted in which the survivors in any given system automatically reproduced themselves (subject to occasional mutation) when their population size was depleted to a critical threshold. Here close background matching readily evolved when prey were presented against a single uniform pixilated environment and when prey were presented against a single uniform spotted environment. As expected, the background matching that evolved in alternating light and dark green environments involved specialism on one or other background, and no intermediate forms evolved. By contrast, a more polymorphic range of phenotypes evolved in the alternating small and large spotted environments. To our knowledge this is the first time that automatically regenerating populations of web based prey have been set up to address evolutionary questions. Our findings have clearly shown conditions under which jack-of-all-trades cryptic forms survive poorly, and, although more work is needed, it may also help explain why background matching frequently appears so specialized in natural systems.

Summarizes several strategic briefings, conference presentations and reports on the topic of logistics management. Covers in turn logistics in China and Japan, including a profile of Braun Electric; methods of improving the supply chain, highlighting new technology, the “bullwhip effect” of distorted information and a case study of Tektronix; logistics in retailing, including direct mail in Japan, home shopping and distribution networks; and applications of the Internet in the logistics field, focusing on “knowledge logistics” (electronic publishing). Concludes with a summary of research conducted by McKinsey which suggests that doing business in a world of plentiful and cheap interactions will require new skills and new ways of thinking and those who anticipate and understand the fundamental nature of the changes will be best placed to exploit the opportunities.

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