JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. American Society of Ichthyologists and Herpetologists (ASIH) is collaborating with JSTOR to digitize, preserve and extend access to Copeia. The mating calls of Bufo a. americanus and B. woodhousii fowleri studied in northern New Jersey and on Long Island, New York, consist of trains of pulses uttered at a rate of from 18 to 59 pulses/sec in americanus and 83-161 in fowleri. Pulse rate is highly dependent on body temperature, and approximately doubles with a 10? C increase. Average duration of call ranges from about 4 to 11 sec in americanus and from 1.3 to 2.5 sec in fowleri; call length is negatively correlated with temperature, but is much more variable than pulse rate. An increase in temperature probably exerts a slight, positive effect on dominant frequency, but the effect is largely obscured by individual variation. In general, increasing body size is accompanied by reduced pulse rate, increased length of call and lowered dominant frequency, but within the range of body size found in one population, the effects of differences in body size on mating calls are usually too slight to be detected readily. Limited data suggest that B. a. americanus of the northern and eastern United States produces mating calls with higher pulse rates (at a given temperature) than does B. a. charlesmithi of Oklahoma and Arkansas. The mating calls of hybrid toads have pulse rates intermediate between those of the parental species. When temperature is taken into consideration, there is no overlap in the ranges of pulse rates of 42 fowleri, 24 americanus and five hybrids recorded in one breeding pond. Pulse rate is perhaps a more sensitive criterion of hybridization than is morphology, because individuals indistinguishable morphologically from one of the parent species gave the calls of hybrids. Judging from mating calls, introgression has not measurably influenced the sympatric populations of fowleri and americanus studied.

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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. This content downloaded from 169.230.243.252 on Tue

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agers, long ago? I hope this question may be disturbing. Our preoccupation with. nomenclature has been at the root, perhaps, of that old jibe which defines ecology as "the painful elaboration of the obvious." I shan't say the accusation is completely warranted, but I think that if it were completely unwarranted, we should resent it less.Another criticism is that we are too concerned with old patterns. Too concerned, according to Bates, with static notions of the climax, or, as Stone suggests, subservient to belief in mysterious processes which man had better not try to change.Here we seem to have a clash of viewpoints-always refreshing and likely to be profitable-for Lutz explicitly states that knowledge of the climax and natural succession are basic to sound forest management, Costello refers to the principle of ecological balance as fundamental in range management, and he and Rickie indicate that the first essential of range and wildlife management is maintenance of harmony between animal populations and their environment.Speaking for myself, I doubt whether too much emphasis has been placed on the concept of balance. The question has particular import at this time because of the development of growing interest by the public at large in relations between man and nature. The ordinary citizen is becoming increasingly aware that, far from being a negligible term in the natural equation, man is a very important term indeed. Whether he has the wisdom and virtue to maintain the equational balance, he certainly has the power to unbalance the equation catastrophically.To me, balance in an ecological system is something that can be demonstrated, and it is not static.It is a condition in which orderly, constructive change can take place, in contrast to the chaotic sequences which follow imbalance, such as the development of overpopulations of livestock and wildlife on the western range, with consequent destruction of the plant cover and accelerated erosion. This dynamic balance, with orderly change, in contrast to the chaotic situation induced by man, is described very well by the medical term "homeostasis."As for future needs, several speakers have emphasized the need for more detailed autecological knowledge. This kind of knowledge will come, and surely it is on its way if only because synecological studies have raised questions regarding the why of observed natural phenomena that can only be pursued by controlled experiments. But we need not think we can write synecology off as some kind of outworn scaffolding useful in the past, of little future interest. Probably the really comprehensive concepts about the interrelations of organisms and environment are still to be developed.We are a long way, for example, from understanding man's place in nature. We cannot understand it until we can appreciate more adequately what we mean by our present, admittedly crude concept of a balance of nature. As one phase of the problem, where does normal geologic erosion leave off and accelerated man-caused erosion begin? As we review th...