ТЕКСТЫ ДЛЯ САМОСТОЯТЕЛЬНОЙ РАБОТЫ
I. ИНФОРМАЦИОННО-ТЕРМИНОЛОГИЧЕСКИЕ ТЕКСТЫ
Текст 1
The modern approach to natural history
The science of life is being put together like a giant jigsaw puzzle ─ a piece added here by the ancient Chinese, a bit by Aristotle, and sections contributed by people like Linnaeus, Darwin and Mendel. We now have some important areas complete, but there is still a long way to go.
From a naturalist's point of view the progress of knowledge can be divided into four stages: what, where, how and why. We are still working on the "what" and "where", of course, though nowadays we have a pretty good idea of which living organisms inhabit the earth with us and where they are found. With Darwin's revolutionary theory we come to the "why" stage in our studies. Why are there so many different kinds of finch in the Galapagos Islands? Why are orchid flowers shaped so curiously? Darwin, too, asked "How?" - how does a plant climb a trellis, and how do tiny corals build whole tropical islands?
One of the foremost naturalists in Victorian times was the French entomologist Fabre. As for as he was concerned, although it was important to make collections of insects it was also important to know how and why they behaved as they did. He was one of the first entomologists to go out into the field and study how insects lead their lives in nature. Not only that, he could write about his discoveries simply and beautifully so that even people who did not understand anything about entomology could appreciate them. J remember when I was ten years old, my brother Lawrence introduced me to Fabre's writings. They opened up a magical world. Here was a man who could tell me why dung beetles so busily made little balls from horse or cow manure and buried them and how the glow-worm overpowers and consumes snails; who could tell me what a praying mantis did on her wedding night and who could describe exciting experiments to prove his theories ─ he once borrowed a cannon and fired it off in front of his house (breaking all the windows) to see if cicadas could hear. Though his main work was with insects, Fabre was interested in the whole of nature from mushrooms to fossils and his writings meant that you were suddenly transported out into the open air instead of, as with so many Victorian naturalists, into a museum.
This tradition has been carried on by modern naturalists such as Konrad Lorenz, through whose studies of animal behavior has emerged the science of ethology.
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Текст 2
Noisy Clockwork: Time Series Analysis of Population Fluctuations in Animals by Ottar N.Bjornstad and Bryan T.Grenfell
The century of studies in population ecology has been dominated by a nested set of debates regarding the importance of various dynamical forces. The first controversy concerned the relative impact of biotic versus abiotic control of population fluctuations. The key question was the relative importance of “noise” (small-scale, high-frequency stochastic influences) versus climactic forcing (larger-scale, often lower frequency signals) versus non-linear interactions between individuals of the same or different species. The second question concerned the impact of intrinsic (i.e., intraspecific) processes, as opposed to extrinsic or community-level interactions, an argument that has been particularly heated with reference to population cycles. A third debate, nested within the latter, concerns the “dimensionality” of population fluctuations; given that most populations are embedded in rich communities and affected by numerous interspecific interactions, can simple (low-dimensional) models involving one or a few species capture the patterns of fluctuations? All these questions have been studied through a number of detailed analyses of specific systems in which theoretical models are linked with long-term studies (often 10 or more generations) through time series analysis.
There has been much parallel and intertwined development of these three dynamical themes, and history testifies to a succession of popularity of the various positions (1). Crudely summarized, early focus on extrinsic influences was replaced by the “density-dependent paradigm” (2) in the 1950s and 1960s. This accelerated in the late 1970s, with the assumption of the potential of dynamic complexity even in simple models, leading to a focus in the 1980s on nonlinearity and the detection of deterministic chaos. Research has focused on two fronts in the past decade: (i) the impact of large-scale climactic forcing, coinciding with the rise in popularity of climate change studies through the early 1990s, and (ii) stochastic non-linear models that combine the non-linear deterministic and (largely) linear stochastic theories. The goal in synthesizing these approaches in recent years is to understand how population fluctuations arise from the interplay of noise, forcing, and non-linear dynamics.
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