The Thermal Warriors: Strategies of Insect Survival

by Bernd Heinrich

Book Overview

All bodily activity is the result of the interplay of vastly complex physiological processes, and all of these processes depend on temperature. For insects, the struggle to keep body temperature within a suitable range for activity and competition is often a matter of life and death.

• Format: Hardcover
• Language: English
• ISBN: 0674883403
• ISBN13: 9780674883406
• Release Date: October 1996
• Publisher: Harvard University Press
• Length: 221 Pages
• Weight: 1.15 lbs.
• Dimensions: 0.9" x 6.3" x 9.3"

Customer Reviews

Regulating Body Temperature - the Key to Insect Survival

The Thermal Warriors: Strategies of Insect Survival Author: Bernd Heinrich 221 Pages Publication Date: 1996 Cambridge, MA: Harvard University Press USBN 0-674-88341-1 When I run, or work outside, or bask in the sunshine at the beach, I get hot. When I can't take any more of the heat, I perspire, I take a break, and I sit in the shade. Likewise, in winter, when I wait for the bus or sit on a ski lift and a cold wind begins to blow, I shiver to warm up. Surprisingly, insects perform similar actions to regulate their body temperature. Bernd Heinrich, author of The Thermal Warriors: Strategies of Insect Survival, introduces us to this concept in the preface to his interesting and in depth work by stating, "We humans engage in endurance contests [marathons] such as these only rarely, for the sheer fun or foolishness of it, or for some symbolic trifle. For insects, however, the struggle to keep body temperature within an acceptable range is constant, and often it is a matter of life or death. Each insect is a "thermal warrior" in a constant struggle with its predators and competitors in the context of its physical environment" (viii). Heinrich, as a physiologist, ecologist, and evolutionary biologist, expertly conveys the fact that thermoregulation is an essential part of insect life. Heinrich begins his book by explaining that thermoregulation is not a relatively new aspect of insect life. The earliest insects, arising at least 350 million years ago, had body temperatures that were a direct reflection of ambient temperature. Thermoregulation has a lot to do with flight, the operation of the insect's flight motor, and the temperature of the thorax and abdomen. Thermoregulation also encompasses the balance of heat production necessary for activity with the rate of heat that can be lost. Heinrich compares the insect flight motor to the engine of an automobile - both need to heat up to perform work and cool down so that they do not overheat and combust. The insect flight motor is biologically complicated with chemical and mechanical sensors that send signals to a reaction center that controls the motor, the wings, and all corresponding muscles. What was most interesting, in these initial chapters of the book, was the high degree of specialization that must occur in the proteins, compounds, and muscles that must work in order for insects to regulate their temperature to perform flight. This specialization, Heinrich notes, is relatively unknown and highly speculative. The degree of adaptation over the wide range of temperatures at which flight mechanisms operate is astonishing. I have observed bees flap their wings while perching on a flower before taking flight, but I never realized that they were warming up, or for that matter, that they had to warm up, lest they couldn't fly. Heinrich gives the example of the tobacco hornworm sphinx moth that heats up in flight due to its large muscle mass. Insects, like this moth, cannot dissipa

Fascinating!!!

Really neat info on how insects keep warm/cool down and why they move in those ways - shivering, bouncing, etc. The text is really easy to read and interesting to get into - the drawings sprinkled in throughout help make understanding that much easier. I don't have a science background - just have an insatiable hunger to learn about our natural world and this book definitely filled one corner of that hunger......Ever see a dragonfly stand up like its doing a headstand? Well its not because it like the head rush (or maybe that too but the book doesn't talk to that) - the reason they do that is on p. 66 - "When the sun is directly overhead some dragonflies assume the 'oblisk' position, which minimizes surface area exposed to solar heating while maximizing the area available for convective cooling." ....all to say, it was a hot day and the dragonfly needed to cool down :) Excellent book!

Unusual topic well presented

The thermodynamics of insects, from flight and thermoregulation to "thermal wars" between predator and prey. This is fascinating hard science presented in a user-friendly format. Short and pithy.

Excellent information, easy to understand

Bernd Heinrich has brought us yet another book that appeals both to the complete layperson and the scientist and provides enough detail and entertainment to keep both happy. The Thermal Warriors provides a fascinating look into the details of insect thermodynamics. Did you know that bees and most other flying insects have to shiver their muscles to warm-up their engines before flying because their flight muscles are adapted to work best at flight temperatures? Did you know that some butterflies have to stop and rest frequently on even moderately sunny days to keep from overheating? Heinrich has taken his in-depth experience in this field and created a summary version for those that want to know more, but don't have any interest in wading through a 600 page monolith. The book is split up into different "problems" that insects must overcome to achieve flight, be active in different environments, and utilize different body shapes and sizes. He explains the physics of the various problems encountered and adaptations to overcome the problems in an easy to read manner. He frequently uses car engine analogies to help things make more sense.My only qualm with this book is that it was over too soon!