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Presents abstracts of articles from a number of journals that deal with the topic of the biology of corals.

Analyses of papers published in from 1961 to 1981 were made from several aspects. Number of papers published has increased year after year. Molluscan endocrinology papers have increased and overtaken annelid publications. During the past 20 yr studies using crustaceans and insects have comprised 25–50% of all endocrine research on invertebrate groups. Papers on protochordates, elasmobranchs, and cyclostomes are few but constant in number, indicating that these three groups are important from phylogenic aspects. Studies on birds and teleosts have increased, while those on amphibians have decreased. Biochemical techniques were employed in 50% of all publications in this journal. Radioimmunoassay has replaced autoradiography. Immunohistochemistry increased in popularity. Studies on the pars distalis and gonads are predominant among all endocrine organs. Research at the molecular level is decreasing, but is increasing at the organismal level. Research at the organismal level may be characteristic of comparative endocrinology. Largely through the initiative of Aubrey Gorbman, was first published in 1961, and the International Committee of the Symposium on Comparative Endocrinology was formed in 1957. Gorbman has produced many students. His original and important contributions are in diversified areas: thyroid physiology and its evolution, hormones and the brain and behavior, cyclostome endocrinology and neurosecretory systems in lower vertebrates. In addition, he has influenced investigators through his ideas of evolution. He has had particular impact on the development of comparative endocrinology in Japan. [ABSTRACT FROM PUBLISHER]

Presents abstracts of articles from a number of journals which deal with the topic of the biology of corals.

Presents abstracts of articles from a number of journals which deal with the topic of biology of corals.

Presents an introduction to the nature of gastroenteropancreatic (GEP) system in line with hormone biology. Details on a symposium which re-examined hormone in honor of researcher Erika M. Plisetskaya; Contribution of the researcher to GEP Physiology; Overview of papers in the symposium.

SYNOPSIS. NO individual has been identified more strongly with the development of Coloradan mammalogy than Edward Royal Warren. Warren's two books on Coloradan mammals represent landmark summaries of our evolving knowledge of the rich mammalian fauna of the state. This paper reviews briefly the history of mammalogical research in Colorado and attempts to place Warren in context in that history. The paper relies almost exclusively on a quantitative and qualitative analysis of Warren's published work, which comprises some 96 papers and books, mostly on the Coloradan fauna. He contributed a number of new records to the state's faunal list, but made little contribution to taxonomy. His nomenclature was uncritical and he made no significant contribution to biological theory. His natural history observations are largely anecdotal (although his papers on beavers in Colorado and Wyoming are of enduring importance). Despite its magnitude, Warren's published contribution has not stood the test of time particularly well. A body of unpublished documentation, however, survives in addition to the published papers. That raw documentation may prove eventually to be Warren's most enduring contribution to science and to Coloradan natural history. Warren provided us, like few naturalists have done, a carefully documented description of biotic normality, a description of a Coloradan environment less disturbed than it is today. [ABSTRACT FROM PUBLISHER]

Examines the works on relative growth and the status of allometry in evolutionary theory. Definition of allometry; Allometry before researchers Julian Huxley and Georges Teissier; Details on their joint paper in 1936.

Presents an examination of the behavior of vertebrates, highlighting the integration of proximate and ultimate causation. Definition of proximate and intimate causation; Historical perspective of proximate and ultimate causation; Events suggesting integration of proximate and ultimate causation.

Lilian Vaughan Morgan was an important geneticist of the first part of the 20th century. She discovered both the attached-X and closed-X chromosomes as part of her extensive research on the X chromosome of . She received A.B and M.S. degrees in Biology from Bryn Mawr College and became an independent investigator in the 1890s at the Marine Biological Laboratory, Woods Hole, Massachusetts. Although her research at the turn of the century was in embryology, she made the successful transition to genetics. In 1904 she married T. H. Morgan, raised four children, managed the Morgan household, and when the children were grown resumed full time research. She always worked independently, and in her lifetime published 16 single author papers. [ABSTRACT FROM PUBLISHER]

Many kinds of sharks are dangerous and apparently unpredictable predators whose behavior is virtually unknown. This is because they are difficult both to maintain in captivity and to observe in the field. However, the purpose of this paper is to review the behavioral information on sharks and, more importantly, to suggest approaches which will accelerate progress in understanding the activities of these animals. Shark behavior has been investigated within the methodological frameworks of both comparative psychology and ethology. Thus the underlying philosophies of these disciplines are briefly discussed. Six approaches for investigating the activities of sharks are presented. Approach I involved intuitive studies drawing upon natural history notes and fisheries statistics, and is typified by Springer (1967). This work set the stage for future quantitative research. Approach II is also intuitive. Here, as typified by Klausewitz (1962), inferences about behavior and ecology are drawn from morphologic and taxonomic considerations. Results appear to be useful in only the broadest of applications. Approach III, an ethological approach we term “structure of behavior,” rests upon direct observation of behavior. The basic rationale underlying this technique, including examples of field and laboratory studies with sharks, is given. While we are at a beginning stage in the ethology of sharks, this approach appears to hold great promise. Approach IV, the study of activity rhythms in sharks, is reviewed. Little is known about such rhythms, which represent short-term temporal activity. Practically nothing is known about long-term activity, i.e., behavioral ontogeny. In Approach V psychological studies of learning are reviewed with emphasis on habituation, operant and classical conditioning in sharks. It is concluded that learning probably plays an important role in the lives of sharks and that they are clearly not the stupid, blindly swimming creatures of folklore. In Approach VI studies of sensory physiology using behavioral techniques are briefly discussed. Results led to the conclusion that sharks are well adapted to detect and respond appropriately to a wide variety of environmental stimuli. Though the difficulties are real and many, the paper ends on an optimistic note, and it is felt that continued effort will unquestionably lead to a significant increase in our understanding of these fascinating animals. [ABSTRACT FROM PUBLISHER]

This paper is a discussion of some of the possible structural and functional modifications of the lung which represent adaptations in mammals living in the sea. Lung capacities of marine mammals seem to be larger than terrestrial mammals especially if they are compared on a lean weight basis. It is proposed that at least in some this represents an important increase in buoyancy which enables these mammals to rest at sea. The importance of the lung as an O store during dives is considered, and it seems that it would be important only to those species that have a low breath-hold tolerance. In their case the O present in the fully inflated lung is from four times to equal that in the blood. In those species with a large breath-hold tolerance the lung O store is a small fraction of blood stores. Several experiments are discussed which indicate that during dives to depth gas exchange between the blood and lungs is low. One of the reasons suggested is compression collapse of the alveoli. This occurs because of the apparent rigidity of the airways which even in the terminal segments possess an unusual amount of muscular or cartilaginous support. The reinforcement insures that during compression the airways will not occlude and trap gas in the alveoli. In fact, in some species, especially otariids and cetaceans, the airways seem overly strong and an additional function is suggested. Studies of mechanical properties of sea lion and whale lungs show that they may be capable of high expiratory flow rates at low volumes. This feature of the lung would make possible an exchange of a large gas volume in very short periods. Such an ability is consistent with the ventilatory behavior of many marine mammals. [ABSTRACT FROM PUBLISHER]

The history of Invertebrate Zoology over the past 40 years can be used to illustrate interest in organisms and some of the ways in which the symposium's question may be interpreted. The study of animal organisms from a holistic perspective has progressed enormously as reflected in changes in described and estimated numbers of species, in the discovery of new higher taxa and in the growth of literature. Generalizations on the biology of animal organisms, however, rest on relatively small samples, and many of the same organisms that have received the most attention in the past continue to receive the most today. Symbiosis and colonial organization have been two important means whereby new organizational levels for organisms have evolved. Ultrastructural research over the past 20 years has provided new evidence in support of the hypothesis promulgated long ago that multicellular animals (metazoans) may have evolved from colonial protistans. Some polymorphic, colonial metazoans have approached or crossed the threshold to a still more complex level of organism. [ABSTRACT FROM PUBLISHER]

This symposium was convened to synthesize recent advances in developing and testing quantitative and qualitative models of territoriality. The goals were to increase the rigor of current models of territoriality, to put field data into a conceptual framework, and to involve a variety of taxa so as to obtain a breadth of perspective not previously available. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. Biogeography has had a long history, but only recently has it started to be more than a descriptive subject. Models have been developed which help to explain patterns of geographical distributions of animals and plants. Examples include dispersal, vicariance, and ecological determinism. The dispersal model proposes that present-day distributions were caused by long distance dispersal among disjunct localities. The vicariance model proposes that the distributions resulted from the fragmentation of formerly continuous distributions with accompanying speciation. Ecological determinism proposes that whatever the historical changes in distribution (dispersal or vicariance), present-day ecological factors are the major determinant of distributions. We too often see in the literature large bodies of data analyzed with respect to only one of these competing models. I organized the symposium to bring together what I thought were particularly interesting examples of each approach. It is obvious from the papers that there are multiple explanations for most species distributions, and that some effort should be made to integrate them. [ABSTRACT FROM PUBLISHER]

Theory can have many different kinds of use in illuminating ecological research. The examples sketched in this paper include: the uses and short-comings of population models currently used in setting catch quotas for whales and for fisheries; the rich array of behaviour displayed by nonlinear equations and its relevance to understanding natural and managed populations; models for the interaction between populations (particularly the regulation of natural populations by diseases); and some general patterns of community organization. The paper concludes with some remarks on the contrasts between public pieties about “The Scientific Method” and the way scientists actually work, from Darwin's day to our own. [ABSTRACT FROM PUBLISHER]

The idea that biological interactions between species restrict their distributions beyond limits set by the inorganic environment was established by plant ecologists well before the work of Volterra, Gause, and the development of modern niche theory. Mechanisms of competition between plant species, and the influence of predation and environmental factors on the outcome of interspecific competition, were demonstrated by extensive field experiments. These early botanical achievements were ignored by zoologists whose subsequent, independently derived ideas about competition paralleled those of plant ecologists to a remarkable degree. Application of niche theory to the real world was closely tied to the advent of the “modern synthesis.” The primary innovation of niche theory was not simply a new appreciation of the possible importance of competition between animals, but the incorporation of an evolutionary perspective to distributional problems largely absent among ecologists since Darwin. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. Non-gravid female clasped by sexually active males emit a release call and thereby signal their unreceptive status to the clasping male. The receptive condition of gravid females is indicated by absence, or inhibition, of the call. This paper provides evidence that arginine-8 vasotocin (AVT) can inhibit the release call by causing water uptake when a female is in an aquatic environment, and suggests that water might exert this effect by means of a mechanical distension of the body wall or internal pressure. This paper also includes evidence that the ovaries are not necessary for AVT's inhibition of the call. The literature dealing with the physiological basis of female frog reproductive behavior and the physiological basis of the release call are reviewed. [ABSTRACT FROM PUBLISHER]

Provides information on the Opisthobranch Swimming symposium which was organized to provide details of motor control from Opisthobranch orders that have swimming members. Contributors to the symposium; Types of swimming; Role of serotonin in modulating swimming activity in opisthobranchs.

SYNOPSIS. This paper reviews the evidence dealing with hormonal controls on egg production in by which the inputs of feeding and mating are integrated. Juvenile hormone, secreted by the corpus allatum, plays a central role in egg production, intervening at several sites to control the duration of egg production. The controls on the corpus allatum are complex and apparently highly redundant, and the necessity for this redundancy is analysed in terms of the strategic advantage conferred on the insect by this network of controls. [ABSTRACT FROM PUBLISHER]

The tempo and mode of morphological evolution are influenced by several factors, among which evolutionary transformations in developmental processes are likely to be important. Comparing the embryos of extant species in an explicit phylogenetic fram work allows the estimation of minimum average rates of evolution in quantitative developmental parameters. It also allows delineation of the maximum time that complex qualitative transformations in developmental mechanism take to evolve. This paper analyzes rates of quantitative and qualitative developmental evolution using examples drawn primarily from echinoderms. The results demonstrate that rates of developmental evolution can be comparable to rates of morphological evolution. There is no indication that rates of evolution in development are lower for earlier stages, contrary to the prediction of “tree” models of epigenetic interactions. In particular, rates of evolution in oogenesis can exceed rates of evolution in adult body size. Rates of developmental evolution can vary by up to two orders of magnitude within a clade. Whether such large scale variation in evolutionary rates of developmental processes is a general phenomenon can only be answered by further study. [ABSTRACT FROM PUBLISHER]

Traditional neuroanatomical methods provide a means for understanding some aspects of cell and tissue organization in the nervous system. However, the boundaries of the field of neuroanatomy have been blurred in the past twenty-five years by interdisciplinary techniques, such as dye-injection methods that combine electrophysiological and anatomical protocols and immunocytochemistry which combines immunological and histological methods. This review therefore takes a very broad view of neuroanatomy, including within this field a variety of “anatomically-based” methods that allow visualization of physiological and molecular features of neurons. Several representative methods are discussed and examples of the data achieved are provided. Although this area of neurobiology has evolved rapidly in recent years, the future holds promise for an even more dramatic revolution as molecular, computer and confocal-microscopic methods are more widely applied to neuroanatomical problems. Neuroanatomy is therefore viewed in this paper as an interdisciplinary field, and this paper might just as appropriately be entitled, “How are neurons visualized?” The answer involves a wide range of methods that allows description not only of static situations, but also dynamic phenomena in neurons. [ABSTRACT FROM PUBLISHER]

Pelagic aquatic environments differ from terrestrial environments in being three-dimensional and relatively homogeneous, rather than two-dimensional and heterogeneous. The present paper examines the causes and consequences of these differences in the context of their influence on the interactions of animals with environmental light. Particular emphasis is placed on light as a determinant of effective modes of crypsis in the two different habitats. The terrestrial world has selected for the expression of crypticity in the form of superficial color patterns. The heterogeneity of this habitat has resulted in evolutionary of these superficial color patterns, often in very closely-related animals. In contrast, in the homogeneous pelagic aquatic habitats, evolutionary on three main forms of crypsis is evident: (1) transparency; (2) reflection of most, if not all visible wavelengths; and, (3) ventral bioluminescence as counterillumination; thus, to be cryptic most animals in these habitats use one or a combination of these modalities to variously transmit, reflect or mimic environmental light. In the present paper, special attention is given to transparency as the most prevalent, yet least understood, of these mechanisms that are used in predator-prey interactions. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. This paper explores the proposition that in morphology, or any other scientific subject, every statement is based on multiple assumptions already in our minds before we begin to teach or do research in the field. Progress in morphology is intimately related to its philosophical and historical foundations. Personalities, social pressures and cultural traditions also play major roles in the often complex and circuitous routes of scientific discovery. General education provides a foundation for understanding these many interactions. Morphology, itself, is a metaphor for inter-relatedness, and this metaphor can be used to explore general education in the broadest sense. Morphology is not only a body of knowledge and processes for producing that knowledge but also groups of people deciding on directions, collaborating on methods, and consulting on concepts. A morphologist is a member of a community of understanding in a culture composed of diverse and often conflicting influences. I suggest that exploring these issues is an important pedagogic tool for discovering and understanding the foundations of morphology as a scientific endeavor. This paper is appropriately dedicated to Professor Milton Hildebrand who understands well the interdisciplinary nature of scientific discovery. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. Precocial and altricial birds have distinctly different patterns of general ontogeny and metabolic/thermoregulatory development. In my laboratory, we have studied the development of thyroid function in Japanese quail () and Ring doves () as examples of precocial and altricial development, respectively. In this paper, I review the literature and our work on the factors that influence peripheral hormone dynamics in birds. The first section of the paper describes adult peripheral thyroid function to set the stage for the developmental picture. Thyroid development is divided into two phases: Phase I, in which the thyroid gland develops functional capacity but there is low thyroid activity in the periphery, and Phase II, in which peripheral thyroid function increases and approaches adult levels. In precocial development Phase I occurs during embryonic life and Phase II begins at the perinatal period. In altricial development, the pattern of thyroid functional development is different and delayed. Peripheral thyroid hormone patterns in both developmental modes are discussed with reference to the factors that determine their dynamics: hormone availability from the thyroid gland, total serum hormone concentrations, the roles of serum binding proteins in regulating freehormone concentrations, hormone turnover and excretion, hormone receptors and thyroid hormone metabolism, especially extrathyroidal production of triiodothyronine from thyroxine. [ABSTRACT FROM PUBLISHER]

Each paper in an American Society of Zoologists' symposium on territoriality generated new ideas for future research. However, since similar themes repeatedly arose, an overview of the symposium revealed the areas in which future research is most needed. Theory far outstrips data on territoriality at this point, and efforts should concentrate on field tests of ideas. Some of the general areas that need study are: the effect of foraging goals and constraints on territorial decisions, the effect of the internal energy or breeding state of the animal in making territorial decisions, the effects of subtle factors such as habitat geometry and the role of neighbors on the cost of defense, the effect of various forms of environmental variability on territorial decisions, the active or passive influence of plants on territoriality, and the effect of scale and mobility in the expression and evolution of territoriality. The study of territoriality is entering a particularly challenging stage of development, because study systems must be carefully chosen and model assumptions thoroughly examined before rigorous experimental tests of hypotheses can be performed. Yet the state of the art is such now that only rigorous tests will advance our knowledge further. [ABSTRACT FROM PUBLISHER]

Major ecological problems of our polluted troposphere include airborne toxic chemicals, acid rain and photochemical smog, all three of which are now recognized as being closely related chemical phenomena. We also recognize that inorder to develop cost-effective strategies for their control, which protect public health and the environment, there must be close scientific interactions between chemists and biological scientists. For example, of rapidly emerging importance is the development of risk assessment evaluations for specific aspects of each of these problem areas. In preparing such assessments, chemists must define the “exposure,” and biological scientists the “effects.” In this paper, I discuss an example of how such close interactions proved indispensible in our search for atmospheric mutagens and carcinogens. Thus, an integrated chemical/ microbiological procedure for the isolation and identificationof particulate chemical mutagens in respirable diesel soot and ambient particles is described. Emphasis is placed on our use of the short-term, Ames bacterial mutagenicity test as a rapid, and relatively inexpensive, means of following the biological activities of these environmental mutagens through the chemical steps of their separation, isolation and identification from highly complex environmental samples. Possible mechanisms of formation of these particulate mutagens are discussed. They include the reactions of polycyclic aromatic hydrocarbons present on the surfaces of combustion-generated particles with gaseous co-pollutants such as nitrogen dioxide plus nitric acid, and ozone. In discussing this research on a societally “relevant” problem, we illustrate the importance of “Science as a Way of Knowing.” We further suggest that this integrated approach to scientific problem solving by chemical and biological scientists might serve as an example of a discussion topic on human ecology for undergraduate courses in the natural sciences. [ABSTRACT FROM PUBLISHER]

In all vertebrates gonadal secretions, through their actions on the central nervous system (CNS), control sex and sex-related behaviors and also regulate production of gonadotropin. Recently, major advances have been made in characterizing the molecular events which underlie these processes. Discussed in this paper are the nature and source of androgens and estrogens; their sites of action within the CNS as determined by steroid implant and autoradiographic studies; some manifestations of brain-steroid interactions, both “triggering” and “organizational”; evidence supporting a conventional genomic mechanism versus alternative modes of action; the critical role of androgen metabolizing enzymes in regulating the quality and quantity of active hormone in close proximity to targets; and some determinants of steroid access to the CNS. Information from nonmammalian vertebrates is reviewed in relation to the major body of knowledge derived from common laboratory species. The intent of this paper is to provide a biological perspective and to stimulate interest in the use of unconventional animal models for future studies. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. This paper examines mechanisms of individual identification in the kin recognition process. In type 1 kin recognition, the individual (, a parent) learns the identifying cues (the “signature”) of particular kin (, offspring) at some stage when there are reliable contextual cues as to kinship (, the parent finds the young in its nest). These kin are subsequently recognized via their signatures in situations in which contextual evidence of kinship is lacking. The primary selection pressure in this case is for a mechanism that can generate a large number of distinctive signatures, and thus permit recognition in large groups. I develop a model that predicts the necessary information capacity of a signature system, and I test this prediction for the signature call of the bank swallow (). The measured information capacity of 17 bits corresponds well to the prediction and, moreover, is substantially greater than that of the homologous call of the similar but non-colonial rough-winged swallow (). In type 2 kin recognition, reliable contextual evidence as to kinship is absent at all times, and kin must be recognized via a signature-matching process. For example, the individual might compare its own signature to that of the unknown individual, inferring kinship if their signatures are sufficiently similar. I describe a multi-locus genetic signature mechanism that would permit discrimination of kin from non-kin, and suggest how this model might be tested [ABSTRACT FROM PUBLISHER]

In 1959, in his seminal paper “Homage to Santa Rosalia,” G. E. Hutchinson asked, Why are there so many kinds of organisms? This paper focused attention on problems of species diversity and community organization that have occupied many theoretical and empirical ecologists for the last two decades. In the present paper I evaluate the attempt to answer Hutchinson's question by considering three topics. First, I reexamine the main themes which Hutchinson developed in “The Homage” and call attention to the central importance of energetic relationships in his view of ecological communities. Second, I examine the development of theoretical community ecology over the last two decades in an attempt to determine why some avenues of investigation, such as competition theory, have proven disappointing, whereas others, such as the theory of island biogeography, have enjoyed at least modest success. Finally, I suggest that future attempts to understand patterns of species diversity might focus on developing two kinds of theoretical constructs: capacity rules, which describe how characteristics of the physical environment determine its capacity to support life, and allocation rules, which describe how limited energetic resources are subdivided among species. [ABSTRACT FROM PUBLISHER]

SYNOPSIS. Rodents discriminate and prefer familiar odors early in life. Almost from birth young rats suckle in response to maternal odor, but suckle less when nipples are cleaned with organic solvents. In two-choice tests, young prefer familiar nest odors, whether naturally occurring or artificially presented, and can even be made to tolerate odors normally aversive or to avoid odors normally pleasant. Variations in maternal diet can alter odor preferences of theyoung. Nest odors can affect vocalization of young rodents. In contrast to the consistent effects of cold temperature and handling in the many rodents studied, nest odors may affect vocalization differently in different species. For example, familiar odors reduce calling in rats, but increase calling in pine voles. Nest odor also alters spontaneous activity in young rats, whichlocomote less when maternal odor is present. In this paper I report that home nest odors enhanced locomotion in rodents of three species (pine voles, ; white-footed mice, ; and wild house mice, ), but that the age at which this pattern occurred and the relationships of nest odors to vocalizations differed among the species. [ABSTRACT FROM PUBLISHER]

In this paper I ask two questions: Is fruit ever limiting to vertebrate frugivores and, if so, do frugivores presently compete for food, either with closely- or distantly-related species? A brief review of the fruiting strategies of tropical plants indicates that fruit can occasionally be superabundant, but it is often produced at low rates and in low quantities. Variation in fruit abundance results from several biotic selective pressures, including variation in the density, diversity, and reliability of potential dispersal agents. To judge from the size structure, dietary similarities, habitat preferences and foraging behaviors of taxonomically-restricted guilds of frugivorous birds and mammals, members of these guilds have competed for food in the past and must occasionally do so today. Unusual climatic conditions can occasionally “upset” phenological patterns and can create food shortages that promote competition among closely-related species of frugivores. Avian and mammalian frugivores, however, probably seldom compete with each other for food in present-day tropical ecosystems. A major reason for this is that many tropical plants have evolved fruits that are attractive to only a limited subset of frugivores (, only birds or only bats). Plants apparently “perceive” qualitative differences in the dispersal services of birds and mammals and attempt to attract members of one group but not the other. [ABSTRACT FROM PUBLISHER]

Ultrasonic vocalizations are very conspicuous during rat mating activity. Two types of calls are produced by both sexes. The first, brief complex calls with the main frequency centered about 50 kHz, occur primarily in conjunction with solicitation and mounting activity. The second type of call is the long, 22 kHz whistle which is emitted mainly by the male during the postejaculatory refractory period, but also by both male and female at other times during the copulatory sequence. The occurrence of ultrasonic vocalizations is correlated with sexual motivation of rats. Males emit more 50 kHz calls before successful mating tests than before tests in which they fail to ejaculate. Furthermore, more vocalizations are emitted by the pair prior to intromissions than prior to mounts without intromission. Just before ejaculation there is a large increase in the rate of calling and, at times, transition by the male to calling at 22 kHz. This latter event may represent physiological dearousal by the male. Following ejaculation, the male characteristically emits 22 kHz vocalizations and exhibits a sleep-like EEG pattern. The function of the postejaculatory vocalization may be to enforce separation between the mating pair, while at the same lime maintaining contact between the partners. Fifty kHz calls, on the other hand, prime and facilitate sexual responsiveness of the female. Tape recorded vocalizations of mating rats facilitate solicitation behavior of estrous females in the presence of castrated males, and such females also show a preference for these sounds in a “Y” maze. Deafening of females does not affect their normal pacing of copulatory contacts, but it drastically reduces their solicitation behavior. The studies summarized in this paper lead us to conclude that ultrasonic vocalizations play a major role in the integration of reproductive activity in the Norway rat, . [ABSTRACT FROM PUBLISHER]

SYNOPSIS. Studies on the nudeohis in various species of Amphibia, including the Mexican axolotl, have contributed to an understanding of the function of the nucleolar organizing region. In the first part of this paper we have reviewed some of the research on nucleolar variants in the axolotl. These variants were recognized in different strains of laboratory reared animals. The phenotypes include diminished nucleolar size and possible alterations in the levels of rDNA. The expression of several of these variant nucleolar phenotypes does not, however, reflect a simple deletion of rRNA genes. Evidence from analyses of several mutant and apparently normal strains indicate that some animals have relatively high levels of rRNA redundancy, while others, including some animals which display variant nucleolar sizes, display “normal” levels. Data on the inheritance of rRNA genome sizes in the axolotl is reviewed. The observation that intermediate levels of redundancy were detected in some crosses is discussed in terms of inheritance data from other organisms. In the second part of this review a variety of information, obtained from studies of various organisms, on nucleolar expression is discussed. [ABSTRACT FROM PUBLISHER]

This paper contains new data and maps concerning distribution of the burnsi and kandiyohi pigment pattern variants of the northern leopard frog, . [ABSTRACT FROM PUBLISHER]