Weather

Because of their weight and relatively large surface area/volume ratio, insects may be profoundly affected by weather, especially by temperature, wind, and rain. Weather is a major factor limiting the abundance of many insect species, especially close to the edge of their range. Its effect may be both direct and indirect. For example, by altering the rate of evaporation of water from the body surface wind may be important in the water relations of the insect. Flight activity (whether or not flight occurs, the direction of movement, and the distance traveled) is also directly related to the strength and direction of the wind. Wind action may also exert indirect effects on insects, for example, by causing erosion of soil or snow so that the insects (or their eggs) are exposed to predators, extremes of temperature, or desiccation. Temperature has both obvious direct effects on development rate (Section 2.1) and less easily quantified indirect effects, for example, on a species' host plants, pathogens, and parasitoids, and is thus a key factor in insect population dynamics. Rain probably exerts its influence on most insect populations only indirectly, notably by affecting the availability and quality of food or the incidence of disease. However, it can occasionally have specific, direct effects. For example, through the formation of temporary pools it provides egg-laying sites for some mosquitoes and it is an important factor in termination of larval diapause for some species in semiarid, tropical climates. In other tropical species, for example, the desert locust, Schistocerca gregaria, which has an adult (reproductive) diapause through the dry season, the arrival of rain serves as a cue for copulation, dispersal, and oviposition (Denlinger, 1986).

Through its effect on the flight activity of winged insects and because insects by virtue of their weight are easily transported on wind currents, wind is an important factor in dispersal, the movement away from a crowded habitat so that scattering of a population results. Though a good deal of insect dispersal is of no obvious benefit, for some species the dispersal is adaptive, that is, confers a long-term advantage on the species by transferring some adult members to new breeding sites. Because of its advantageous nature, physiological, structural, and behavioral features that facilitate adaptive dispersal (= migration) will become fixed in a population through natural selection.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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