Primates show a strong positive relationship between body weight and home range area. Dietary habits also influence home range area. Folivorous primates occupy smaller home range areas for their body weight than do frugivores and omnivores. Primates generally require smaller home range area per individual than solitary terrestrial mammals, but primates living in social groups have much larger total home range than individual solitary mammals. This trend may necessitate higher expenditures of energy in food-gathering or modifications in movement patterns.

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Several of Anisoptera maintain their body temperature more constant than ambient temperature. Species that spend most of their active period on perches (perchers) and make only short flights thermoregulate heliothermically, primarily by means of postural adjustments. Some of the species that fly continuously (fliers) are endothermic regulators during flight. They control body temperature by: (1) controlling metabolic heat production by alternately using gliding or powered flight; (2) controlling heat loss by altering circulation between thorax and abdomen. Small fliers are unable to regulate well because they are subject to high rates of convective heat loss. Cooling constants, as defined by Newton's law of cooling, are related to thoracic weight by a negative power function over a wide size range. Cooling constants are higher in live dragonflies than in dead ones, a difference that is accentuated at high ambient temperatures. High cooling constants at high temperatures probably result from increased rates of circulation. Most fliers, and some large perchers, are able to elevate their body temperature by "wing—whirring." In some species the rate of heat production apparently varies in response to ambient temperature. The body temperature at which flight begins after warm—up is positively correlated with body weight, probably because wing loading increases with increasing body size. The maximum voluntarily tolerated temperature and the threshold of heat torpor of several species were determined. Both parameters are correlated with habitat. The minimum temperature at which flight is possible is positively correlated with body weight and is slightly higher in tropical dragonflies than in temperate zone species. Body temperature is probably more variable relative to air temperature in tropical than in temperate zone species. The ability of dragonflies to maintain a relatively constant body temperature is determined primarily by climate, body size, and behavior.

Every year billions of butterflies, dragonflies, moths and other insects migrate across continents, and considerable progress has been made in understanding population-level migratory phenomena. However, little is known about destinations and strategies of individual insects. We attached miniaturized radio transmitters ( ca 300 mg) to the thoraxes of 14 individual dragonflies (common green darners, Anax junius ) and followed them during their autumn migration for up to 12 days, using receiver-equipped Cessna airplanes and ground teams. Green darners exhibited distinct stopover and migration days. On average, they migrated every 2.9±0.3 days, and their average net advance was 58±11 km in 6.1±0.9 days (11.9±2.8 km d −1 ) in a generally southward direction (186±52°). They migrated exclusively during the daytime, when wind speeds were less than 25 km h −1 , regardless of wind direction, but only after two nights of successively lower temperatures (decrease of 2.1±0.6 °C in minimum temperature). The migratory patterns and apparent decision rules of green darners are strikingly similar to those proposed for songbirds, and may represent a general migration strategy for long-distance migration of organisms with high self-propelled flight speeds.