Robert E. Gatten

Behavioural fever in the turtles Terrapene carolina and Chrysemys picta

Abstract 1. 1. The body temperatures selected by box turtles ( Terrapene carolina ) and painted turtles ( Chrysemys picta ) in thermal gradients were measured before and after they were injected with live bacteria ( Aeromonas hydrophila ). 2. 2. Mean body temperatures increased 4–5°C following infection. 3. 3. Turtles are therefore capable of developing behavioural fevers as are certain iguanid lizards.

Activity metabolism of lizards after thermal acclimation

Abstract 1. 1. I tested the hypothesis that thermal acclimation necessarily exerts the same effect on resting metabolism and on aerobic and anaerobic activity metabolism in Anolis carolinensis and Sceloporus jarrovi , diurnally active iguanid lizards that exhibit reduced winter activity but not prolonged dormancy and that are often active on warm winter days. 2. 2. Cold acclimation reduced the total metabolic scope for activity in these lizards by 33–40%. The benefits of winter activity must outweigh the increased risk of predation that presumably accompanies this reduction in capacity for intense, short term muscular exercise. 3. 3. Acclimation did not influence resting metabolism, aerobic activity metabolism, and anaerobic activity metabolism in parallel ways.

Thermal selection by an amphisbaenian trogonophis wiegmanni

1. 1.|Trogonophis wiegmanni is a limbless, fossorial reptile of the order Amphisbaenia. 2. 2.|Body temperatures selected by these animals in a laboratory thermal gradient were higher in the afternoon and early evening (x = 23.2°C) than at other times x = 21.8°C). 3. 3.|The body temperatures selected by this species are lower than those of most other reptiles.

Activity Metabolism of Salamanders: Tolerance to Dehydration

The oxygen consumption and total body lactate concentration of specimens of the terrestrial salamander Plethodon jordani were measured at rest and after 5 min of forced locomotion, at full hydration (100% of standard body mass) and after dehydration to 85% of standard mass, at 15 and 25?C. In addition, we measured standard and activity oxygen consumption of specimens of newts, Notophthalmus viridescens, in their terrestrial stage (efts), at 100% and 80% of standard mass, at 15?C. Dehydration had no effect on the oxygen consumption of these salamanders at rest or during induced activity. Furthermore, dehydration elicited no change in the resting or post-activity lactate concentration. The reduction in voluntary foraging activity by terrestrial salamanders during dry periods cannot be attributed to a dehydration induced loss in the capacity to power locomotion by aerobic or anaerobic means.

The use of anaerobic metabolism by frogs in a breeding chorus

Abstract 1. 1. Male spring peepers ( Hyla crucifer ) were captured as they vocalized in a breeding chorus and immediately frozen in liquid nitrogen. 2. 2. These frogs had whole-body lactic acid concentrations nearly twice those of control frogs resting in the laboratory at the same temperature and time of day. 3. 3. We suggest that the energetic cost of vocalization for spring peepers exceeds their anaerobic threshold, and activity of the muscles involved in calling is supported partly by anaerobic metabolism.

Thermal acclimation of activity metabolism in desert lizards (Urosaurus graciosus and U. ornatus)

Abstract 1. 1.|We acclimated specimens of Urosaurus graciosus , a hibernator, and U. ornotus , a winter-active species, to 5°C in winter and 25°C in summer. 2. 2.|Acclimation had no effect on the ability of either species to utilize glycolysis during 30 s of intense exercise at either 15 or 35°C. 3. 3.|Cold acclimated individuals of U. ornatus will apparently return to resting lactate levels more quickly following the end of exercise at 15°C than will warm acclimated ones. 4. 4.|Cold acclimated specimens of U. graciosus have a lower resting oxygen consumption at 5°C than warm acclimated ones. However, acclimation had no effect on the resting oxygen uptake of individuals of U. ornatus at either 5 or 35°C.

Individual Variability in Sprint Performance, Lactate Production, and Enzyme Activity in Frogs (Rana pipiens)

We measured the sprint performance, lactate concentration in two muscles at the end of exercise, and activity of two glycolytic enzymes in those two muscles of 24 Rana pipiens. Differences among individuals in sprint performance were not associated with differences in lactate level or enzyme activity in the gastrocnemius or triceps femoris. The concentration of lactate in the gastrocnemius was positively associated with gastrocnemius lactate dehydrogenase (LDH) activity but not with gastrocnemius phosphofructokinase (PFK) activity. In contrast, triceps femoris lactate concentration was negatively as- sociated with the activity of PFK but was not related to the activity of LDH in that muscle. Individuals within a population of amphib-

Cardiovascular correlates of exercise in snapping turtles, Chelydra serpentina.

1. Heart rate increased with a rise in body temperature (10-30 degrees C) and with induced physical exercise in snapping turtles. 2. Maximum heart rate increment occurred at 30 degrees C. 3. Standard oxygen pulse did not change with a rise in temperature. 4. Oxygen pulse during exercise and oxygen pulse increment were maximal at 10 degrees C and minimal at 20 degrees C. 5. The increase in heart rate with exercise accounted for only 9-22% of the increase in oxygen transport during activity; the remainder was provided by a rise in cardiac stroke volume and/or A-V difference.

Thermal insensitivity of oxygen pulse in spontaneously-active juvenile alligators

Abstract 1. 1.|Oxygen consumption and heart rate of unrestrained, spontaneously-active juvenile alligators in water rose in parallel between 20 and 30°C. 2. 2.|Consequently, oxygen pulse was essentially constant over this temperature range. 3. 3.|The increased need for oxygen transport between 20 and 30°C was met entirely by a rise in heart rate; there was no need for an increase in the product of systemic stroke volume and oxygen extraction by the tissues.