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We examined the hypothesis that increased aggression results in decreased survivorship. We tested this hypothesis by increasing aggression of free-living male lizards Sceloporus jarrovi with testosterone implants and evaluating the effects on survivorship. A previous study showed that testosterone-implanted males were more aggressive than controls, suggesting a greater degree of success in male-male competition. Results of the present study show that the same testosterone-implanted lizards experienced greater mortality. Testosterone-treated males were also seen more frequently and more conspicuous ones were less likely to survive. Testosterone-treated males lost more weight over the summer. In controls, survivorship was negatively correlated with the body weight index. These data suggest that conspicuousness and energetic demands interact in their influence on survivorship. Thus, the natural plasma level of testosterone may be at an optimal level balancing any potential selection pressures for a higher level of testosterone through sexual selection with selection pressures for a lower level through a decrease in survivorship.

Dialysis clearance of cimetidine in patients receiving peritoneal dialysis, hemodialysis, and hemoperfusion was compared in stable and seriously ill patients. Two methods of determining dialysis clearance were employed, one of which was the method employed for cimetidine previously in the literature. Cimetidine clearance was lowest for peritoneal dialysis (5 ml/min), intermediate for hemodialysis (28 ml/min), and greatest for hemoperfusion (85 ml/min). Using both methods to calculate dialysis clearance, we found that cimetidine clearance during dialysis has been overestimated. In addition, pharmacokinetic analysis revealed that peritoneal and hemodialysis apparently removed cimetidine from the central compartment only, whereas hemoperfusion apparently removed drug from the peripheral compartment as well. A possible mechanism to explain this difference is based on the observation that hemodynamic changes occur during hemodialysis that may not be seen during hemoperfusion. No dosage adjustment need be made when patients receiving cimetidine undergo any form of dialysis; hemoperfusion may be of some benefit in removing drug from the central as well as tissue compartments in an acute overdose situation.

The testes of male white-crowned sparrows, Zonotrichia leucophrys gambelii, subjected to a photoregimen of 12-h days (12L 12D) undergo quasiannual cycles of repeated growth and regression. These cycles decrease successively in period and amplitude and are not accompanied by postnuptial molts. This suggests that they are not physiologically equivalent to those of birds subjected to natural photocycles. Our results demonstrate that transfer of white-crowned sparrows undergoing testicular regression on 12L 12D to long days (20L 4D) induces both testicular growth and increases in plasma levels of luteinizing hormone at normal rates for 20L 4D. These data indicate that testicular regression on 12L 12D must be induced by mechanisms other than the development of photorefractoriness, which is the normal cause of regression on natural photocycles. This suggests very strongly that daylength functions as a driver of the independent components of the annual cycle rather than, as in some other species, a Zeitgeber for...

In free-living male white-crowned sparrows (Zonotrichia leucophrys), plasma levels of testosterone, 5α-dihydrotestosterone (DHT), and luteinizing hormone (LH) decrease precipitously at onset of incubation. The hypothesis that this decrease is a response to the simultaneous cessation of estradiol-dependent solicitation displays by females was tested in an experiment on free-living pairs. Solicitation displays were prolonged by implanting females with subcutaneous estradiol capsules and releasing them. Subsequent capture and blood sampling of the mates of these females showed that they had significantly higher plasma levels of testosterone and DHT than did control males, but results for LH were equivocal. Nevertheless, these results support the above hypothesis and suggest that hormone-behavior interactions are important even in free-living animals exposed to the entire spectrum of environmental information.

It is widely recognized that successful reproduction requires an organism to synchronize precisely its reproductive physiology and behavior with events in its environment (Farner and Gwinner 1980, Wingfield 1983). This has caused all organisms to evolve interactive links among these factors.

Previous experiments have shown that expression of mounting behavior in sexually inexperienced, adult male white-crowned sparrows does not require elevated plasma levels of androgen; adult males maintained on nonstimulatory short days mount sexually receptive females. The experiments reported here demonstrate that (1) sexually inexperienced, prepubertal males maintained on nonstimulatory short days show very low mounting rates in response to female sexual displays; (2) these males exhibit high mounting rates when exposed to stimulatory long days but androgen treatment on short days is ineffective in stimulating high mounting rates; and (3) prepubertal castration has no effect on the expression of mounting behavior by photostimulated adult males. Thus, there is no evidence that mounting behavior of adult male white-crowned sparrows depends on androgen.

Seasonal changes in testosterone levels in male mountain spiny lizards (Sceloporus jarrovi) are correlated tightly with seasonal changes in intensity of aggressive territorial defense. Testosterone levels are lowest in the winter when males aggregate, are moderately elevated during the summer when males show low-intensity territorial defense, and are highest during the fall breeding season when males show high-intensity territorial defense. In this study, we tested the hypothesis that changes in testosterone levels cause these seasonal changes in territorial behavior. We experimentally increased and decreased circulating testosterone levels in free-living males during the summer, when they display non-breeding season territoriality. Artificially increasing testosterone levels to levels equivalent to the breeding season significantly increased some, but not all, measures of territorial aggression. Levels of aggression attained, however, were still well below those typical of breeding season males. This implies that the transition to full breeding season levels of aggression is caused only partly by an increase in testosterone levels. Castration of males during the summer had no effect on several measures of territorial aggression. Thus the activation of nonbreeding season territoriality, which precedes testicular recrudescence by several months, is relatively unaffected by testosterone levels. Taken together these results suggest that the same behavior, in this case territorial aggression, may be controlled by different mechanisms in different seasons.

Cnemidophorus uniparens is a unisexual lizard that reproduces by parthenogenesis. Individuals of this species display male-like and female-like copulatory behaviors during different phases of the ovarian cycle suggesting that these pseudocopulatory behaviors are hormonally activated. To learn more about both the endocrinology of parthenogenesis and the possible hormonal activation of male-like copulatory behavior in female individuals, we (1) characterized changes in plasma levels of the sex steroid hormones progesterone, 5 alpha-dihydrotestosterone, testosterone, and 17 beta-estradiol during the ovarian cycle in both free-living and captive individuals, and (2) measured sex steroid hormones in plasma collected from captive individuals immediately after they expressed male-like or female-like copulatory behavior. In general, the pattern of secretion of ovarian hormones in C. uniparens appears to be similar to that of other oviparous vertebrates with similar reproductive cycles. Estradiol is elevated only during the preovulatory phase, whereas progesterone increases slightly during vitellogenesis and then increases dramatically following ovulation. Circulating levels of androgen are very low and are generally below the sensitivity of our radioimmunoassay at all stages of the ovarian cycle. The hormonal correlates of female-like copulatory behavior suggest that, as in other vertebrates, female receptivity is activated by a synergism of estradiol and progesterone. There is no evidence that the hormonal cycle has been altered to produce elevated levels of androgens during the phase of the cycle when male-like behavior is expressed. Rather it seems more likely that the central nervous system has evolved a novel response to a typical pattern of ovarian steroid hormone secretion. At present, the best hormonal correlate of male-like behavior is that changes in plasma levels of progesterone closely parallel changes in probability of expressing male-like behavior.

Two aspects of hormonal control of aggressive territorial behavior in male mountain spiny lizards Sceloporus jarrovi were studied. First, testosterone (T) implants were given to free-living castrated males during the breeding season. These implants fully restored breeding season levels of aggressive and sexual behavior. Earlier studies showed that identical implants given to free-living males during the nonbreeding season did not induce full breeding season levels of aggression. The full effectiveness of these implants during the breeding season indicates that the lack of effectiveness in the nonbreeding season was not due (1) to the need to replace additional gonadal factors or (2) to ineffectiveness of tonic delivery by the implants. It is more likely that males are less sensitive to T during the nonbreeding season or that other cues present in the breeding season environment synergize with T to induce full levels of aggression. Thus, seasonal changes in aggressive behavior in male S. jarrovi cannot be explained simply as a direct response to changes in circulating levels of T; other environmental factors play a necessary role as well. In the second phase of the study, changes in aggressive behavior of free-living T-implanted castrates were monitored following staged encounters with other males. Despite their inability to alter secretion rates of T, the T-implanted castrates still showed a rapid postencounter increase in aggressive displays that was identical to controls. Previous results showed that this dramatic postencounter increase in aggressive behavior is not accompanied by simultaneous changes in circulating T. Together, these results now allow the hypothesis that this rapid behavioral change in aggressive behavior is caused by simultaneous changes in circulating T levels to be confidently rejected.

Already trying to carry out Russell's kind of *Start on campus and expand. in organizing. *Interested particularly in BR's pacifism, Inake it comprehensive. Work with McMaster. No reason for rival journal to Russe~~. *Young "Russelophile". Dedicated. Entrance corridor to apartment has "The Bertrand Russell Memorial Alcove". *Applauds. Suggests some programs. *Delighted. *Busy but interested" work. *1£ anything I can do, calIon me. *A priVilege to cooperate. Capitalize on Einstein peace experiences. *Don't believe in cultist Preservation Societies. *Those who thought of organizing are best qualified to proceed. *Start as broadly as possible. Attract as many as possible of BR admirers. *Main interest is BR's parents, not BR. *Very interested and very willing to help. Combine education and action. *Further Russell's social and political goals. Further the ideas behind the War Crimes Tribunal. a prog ressreport

Termination of breeding, the development of photorefractoriness, subsequent postnuptial molt, and fat deposition precede autumnal migration in White-crowned Sparrows (Zonotrichia leucophrys). The timing of these postreproductive functions differs from that of analogous vernal functions because they are neither synchronous within the population nor uniformly coincident with environmental stimuli. We hypothesize that the expressions of autumnal functions are internally coupled and that they result from a separate process initiated by the increasing vernal daylength. Our data concerning the effect of various photoregimes on testicular regression, postnuptial molt and fat deposition of Z. 1. gambelii are consistent with the following generalizations: (1) on daylengths that exceed 16 h these processes begin after 40-60 days of photostimulation, inversely related to daylength; (2) transfer of photostimulated (20L 4D) males to an intermediate daylength of 12 h near the end of the testicular growth phase blocks the expression of autumnal functions, although their expression is not blocked if the birds are photorefractory when transferred; (3) males transferred from 12L 12D to 20L 4D in various stages of testicular development begin postnuptial molt after a fixed number of days regardless of the stage of testicular development at the time of transfer; (4) rates of postnuptial molt and fat deposition are inversely related to the daylength to which the birds are exposed when these functions occur, which may explain the acceleration of preparation for autumnal migration in late-starting individuals. Therefore, the systems that control autumnal processes appear not only to be independent of those that regulate analogous vernal processes, but also appear to rely more on internal coupling to integrate these functions than do the latter. The physiological preparation that precedes migration usually involves several functions that require coordination--activation (spring) or inactivation (autumn) of the reproductive system, hyperphagia, and fat deposition, and usually at least a partial molt (Stresemann and Stresemann 1966, Farner and Lewis 1971, Murton and Westwood 1977, Wingfield and Farner 1980). These processes occur in a species-specific order and are temporally separated in small avian forms, although the extent of separation varies among species (Stresemann and Stresemann 1966, Payne 1972, Farner et al. 1980). Although the mechanisms that ensure that these functions occur at the proper time and in the proper sequence have been extensively studied in the migratory races of the Whitecrowned Sparrow (Zonotrichia leucophrys), they remain only partially understood. Differences in preparation for vernal and autumnal migration under natural conditions suggest that different control mechanisms are employed in these two seasons. Preparation for spring migration is synchronized within a population of Z. leucophrys wintering at a given latitude because it appears to be initiated in direct response to increasing daylength (Farner and Wilson 1957, King 1961, King and Farner 1965, Mewaldt and King 1978b). In contrast, preparation for autumnal migration is less synchronous within populations because it does not begin until the birds finish nesting. If a clutch or brood is lost, a pair may renest and delay onset of postnuptial molt, although there is a compensatory acceleration of the molt (Wingfield and Farner 1979). In addition, the decreasing daylength of late summer and autumn differs from lengthening days of spring as predictive information for fall migration (King 1963). Because of (1) lack of synchrony among individuals with the same environmental information and (2) individual differences in rate of preparation due to renesting, i seems likely that this sparrow relies on external information to coordinate its post-repro

information in the classroom. Optical-videodisc systems provide a computer interface, a screen for multiple visual display, and the dual capabilities of interaction and networking. Use of computer simulationsforforecasting, music and video for communicating abstract concepts, and convergence of statistical with visual data are advantages far outweighing current limitations. Not only is the new technology adaptable to different teaching situations, it offers a well-rounded, unique, and relevant view of sociology.