bluuebunny/crossref_metadata_2025 huggingface dataset:
Leaving the House: The Solo Performance of Deborah Hay
Authors: Jeffers Bill
Published: April 2006

Emptiness looks like an absence of something. No, it is not. It is a presence of something infinite.

Bhagwan Shree Rajneesh

The same materials I use dancing are used in my life. The same rules apply to dancing that apply to my life. Everything said about dancing is a reflection of myself. The dance is any moment when I am clearly in the act of doing just what I am doing.

The performances usually begin for us in setting up the space on the previous night. The process is similar each time. We both approach it as a kind of ritual.
The Theatre on Chekhov Street
Authors: Law Alma H.
Published: April 2006

“Have you been to the Theatre on Chekhov Street?” was a question often heard in Moscow in the mid-seventies whenever people interested in theatre got together. Actually, to call it a “theatre” was something of an exaggeration. What it really amounted to was a room in one of those old communal apartments still left in the center of town, the kind that has a shared kitchen and bathroom, and sometimes as many as a half dozen doorbells outside the door. The brainchild of Igor Vasilyev, a young actor and director at the Moscow Art Theatre, the Chekhov Street group operated on and off for about seven years. (To my knowledge they have since disbanded, though not for the first time.)

In recent years, theatre groups such as Vasilyev's have been springing up like proverbial mushrooms after an autumn rain, especially in theatre-starved Moscow and Leningrad.
The Mysteries of Ceronetti and Tedeschi
Authors: Cirio Rita
Published: April 2006

Ten or twelve spectators attend each performance, and that is too many. The size of the audience is partly by choice, and partly it is forced by the size of the theatre, which is a small living room. The play is called I Misteri di Londra (London's Mysteries). A panorama of Victorian society written, prepared, animated, and interpreted by Guido Ceronetti and his wife, Erica Tedeschi, with the assistance of two young women from the neighboring apartment, it is performed by beautiful marionettes.

Guido Ceronetti is a writer and poet and a translator of ancient texts. In newspapers and periodicals, he is an ironic moralist who doesn't believe in progress and has a pessimistic vision of contemporary society. This is something that is not appreciated by the progressive Roman intelligentsia, who have marked Ceronetti as reactionary. Ceronetti, then, is an isolated and singular character in the Italian cultural field.
Theatre in the Corridor
Authors: Veltruský Jiří
Published: April 2006

“Theatre in the Corridor” was written, in Czech, in December 1939; that explains why the first paragraph sounds rather anachronistic. It has remained unpublished for nearly forty years.

This was my third attempt to write a theoretical paper, after “Man and Object in the Theatre,” published in 1940 (English translation in: Paul L. Garvin, ed., A Prague School Reader on Esthetics, Literary Structure, and Style, Washington, D.C., 1964) and “Mácha's Conception of the World,” published the same year.

My approach followed the general theory of the Prague Linguistic Circle, focusing on the concepts of structure and sign. But I was much more influenced by the Prague School's poetics, linguistics, and general esthetics than by its sporadic studies about the theatre, which I found somewhat loose in their reasoning.
Roberta Sklar: Toward Creating a Women's Theatre
Authors: Brunner Cornelia
Published: April 2006

Roberta Sklar is one of the three artistic directors of The Women's Experimental Theatre and a co-author with Clare Coss and Sondra Segal of The Daughters Cycle Trilogy: Daughters, Sister/Sister, and Electra Speaks.

Sklar began her work as a student-director at Hunter College in 1960. She was active in the off-Off-Broadway theatre movement at its inception in the early sixties and frequently directed new plays at the Caffe Cino. In the mid-1960s she joined The Open Theatre and was the co-director of the major ensemble works The Serpent, Terminal and The Mutation Show and directed Beckett's Endgame. These works toured both the United States and Europe and have been widely acclaimed. Throughout the sixties she worked extensively with playwrights and actors in the creation of new works and new work methods.

In the 1970s she began an ongoing research into the development of a feminist esthetic for the theatre.
The German Raum
Authors: Riddell Richard
Published: April 2006

West German theatre, says critic Günther Rühle, is currently fraught with insecurity about where it is going and what its function is. That may be, but there's no question that the theatre has changed considerably over the past two decades and entered an as yet ill-defined post-Brechtian age. Gone are the productions of coolly staged parables, instructing the audience in how the world might be changed through rational, social action. Gone are the bright, evenly lit settings, sparsely furnished and purged of destructive atmosphere. And gone, too, is whatever bond once existed between the performers and the audience. That relationship, says Brecht Schüler Peter Palitzsch, is now “deeply disturbed.”

The German director has become the great interpreter, probing texts, usually the classics, searching for something that matters to contemporary man. The results of his dramaturgical investigations are subjective, fragmentary, and generally bewildering to an audience who hasn't accompanied him on his month- or year-long journey of discovery. His insights are not always theirs. Rich material imagery fills the stages, and it is personal, often violent, and tinged with expressionism. The Prince of Homburg stands naked in a field of potatoes as he is pardoned. The chorus in Antigone, consisting of a single contemporary woman, smears animal organs on her face as she speaks of Haemon's impending death. The actors in Shakespeare's Winter's Tale slip and slide around a stage decked with Mattel “Slime.” Vernunft (reason) has given way to Sinnlichkeit (sensuousness).
The Thingspiel and Das Frankenburger Wurfelspiel
Authors: Gadberry Glen
Published: April 2006

The Thingspiel movement developed as a result of the “new world epoch” begun by Adolf Hitler and the National Socialist Party when they came to power in 1933. During the first years of the Third Reich, the party leaders effected a reorganization of German life, a reorganization that was to be consistent with the philosophy and the world view, the Weltanschauung, of National Socialism. The theatre, the drama, and all the arts were not exempt from this program. Significant changes were demanded on two fronts: The “outmoded” and “inferior” genres in existence prior to 1933 were discouraged or prohibited and in their place, a new order of German art was to be founded. In the dramatic arts, the Thingspiel was the example of this new artistic order, receiving major state support and encouragement. The Thingspiel was to become the National Drama of Nazi Germany.
From Vilna to Vaudeville: Minikes and Among the Indians (1895)
Authors: Slobin Mark
Published: April 2006

Recently the Yiddish theatre has been the object of considerable study, translation and revival; yet the world of Yiddish vaudeville remains virtually untouched. This is odd, considering that what we would now call vaudeville skits and playlets were among the very first products of the Yiddish stage (1870s), while similar material is still being presented to Yiddish-speaking audiences today. It is almost a truism to state that the rise of the Jewish-American comedian in the 1950s and 1960s was rooted in the low humor of the Borscht belt, but few have shown any interest in tracing the genealogy further back. One of the reasons for this neglect has been the scorn with which Jewish theatre critics, historians and activists view all ethnic entertainment not directed towards creating an “art” theatre. An even more important impediment is the almost total lack of surviving printed or manuscript versions of early Yiddish vaudeville.
Alexis Granovsky and the Jewish State Theatre of Moscow
Authors: Adler Lois
Published: April 2006

This is great art. Great art. External impressions and soul disturbances. Word-sound, blood-sound, color-sound, image sound. There are calls, voices, cries, choirs. It is jest and terror…and human abstraction to the last; it is indeed pantomime with the element of infinity. Something miraculous. Great art…Sum total: Here is an excellent example of all the possibilities in theatrical art. Three, four, five fields intermingled: word, song, dance, picture and behavior. Stepped up to the end. Not a dead point the whole evening. Not for a second do they grow slack. Word-play, song-play; cornmedia dell'arte—between them, temple chants, puppet show, variety acts, almost a circus—and humanity. Amazing.
“Drive,” She Said: The Dance of Molissa Fenley
Authors: Banes Sally
Published: April 2006

Molissa Fenley's choreography bewilders the eye, entices the ear, and challenges both the memory and the intellect. Incessant, everchanging motion, saturated with polymorphous arm gestures, performed to a driving, repetitive, percussive beat, the dances are complex series of tensions between constancy and mutability, structure and disorder, abstraction and imagery, exoticism and familiarity, social and theatrical forms.

American dance audiences are accustomed to watching ballets composed of legible phrases, often matched to equally distinct musical patterns. The traditional modern dance creates a succession of expressive postures and gestures that prompt the spectator to arrange them in a narrative flow or a metaphoric gestalt. The achievement of post-modern dance was to isolate an even smaller unit of perception in dance—to frame the posture, gesture, or movement itself as the central subject of the dance—either by repetition or complexification.
Two Performance Pieces by Margaret Fisher
Authors: Bochenek Gail
Published: April 2006

In the performance area are two wooden-frame tents side by side. They are 8 feet square, 6 feet at their apex, and covered with white muslin. The “insect” tent is at the right, tent flaps open, a duplicate miniature tent suspended within the opening. Two flourescent industrial lighting fixtures form a bright “V” upstage on the tent floor. From the opening a clear plastic tube coils its way over to the “scientist” tent at the left. This tent is closed, except for a triangular window centered on its front wall. It is illuminated by a blue light from within.
Mary Overlie: I Was a Wild Indian Who Happened to Dance
Authors: Sommer Sally R.
Published: April 2006

Mary Overlie's demeanor is quiet and thoughtful. She speaks calmly, her words carefully chosen, analyzing ideas. The brown hair is always pulled back from the face, the face is always free of makeup; the body is long and lean, the ideal dancer's body, and her gestures tend to be spare. If the impression she gives is of almost shy reserve, it reflects only part of the personality.

Born in Bozeman, Montana in 1946, Overlie stayed there until she was 17. For a short time following her graduation from high school, she tried to be a sign painter but “couldn't focus on it.” That interest has been refined and converted to an interest in calligraphy. In fact, she often uses the word “calligraphy” to describe the patterns and shapes made by the body in space.
Elaine Summers: Moving to Dance
Authors: Wooster Ann-Sargent
Published: April 2006

Elaine Summers has two identities: a respected choreographer coming out of the Judson Dance Theatre and a highly influential teacher of Kinetic Awareness, a system permitting an extraordinary range and ease of movement that has been studied by many people in the performing arts.

Summers began her dance training by studying ballet as a child. She attended the Massachusetts College of Art and, because degrees in dance were not offered at that time, studied to become an art teacher. She attributes her interest in the breakdown of forms into their component parts to her Bauhaus-oriented art training. During her sophomore year, she studied briefly with Martha Graham and Merce Cunningham in New York. After graduating, she taught art for three years and then went to St. Louis where she taught dance to the mentally ill. In 1952 she came to New York to study dance at Juilliard.
Ecology of Alpine Larch (Larix lyallii Parl.) in the Pacific Northwest
Authors: Arno Stephen F. , Habeck James R.
Published: April 2006

Alpine larch (Larix lyallii) grows in or near the timberline zone on high mountains of the inland northern portion of the Pacific Northwest. Unlike other subalpine conifers, which are evergreens, this deciduous larch displays an affinity for cold rocky sites and often grows in tree form higher up on north slopes than even krummholz (shrubby) forms of its associates. Overstory and understory vegetations in alpine larch communities were only indirectly correlated. Vaccinium scoparium, Luzula glabrata, and Phyllodoce empetriformis were the most common understory dominants. The distinctly snowy—cold—timberline nature of alpine larch habitats is emphasized by the presence of Cassiope mertensiana, Phyllodoce glanduliflora, and Abies lasiocarpa krummholz among the 11 most common understory species. Unlike the larch, which is generally restricted to the timberline zone, nearly all associated plants have broader distributions in the subalpine forest proper or above tree limit. Alpine larch is a climax species on a wide variety of sites too severe for the more shade tolerant evergreens to form unbroken stands because of shortness of growing season, rock terrain, avalanches, blizzards, or extreme dryness or bogginess. When alpine larch ascends into what would otherwise be a strictly alpine habitat (above the limits of other conifers), its stands apparently modify the surface environment since subalpine understory species are generally able to ascend with it. Rarely the undergrowth is dominated by tundra species. Alpine larch is superior in invading freshly glaciated sites. The positive correlation of alpine larch to acidic substrates poor in mineral ions is in contrast to the substrate relationship of many other timberline conifers, which are calciphiles.
Vegetation Analysis of North and South Edges in a Mature Oak‐Hickory Forest
Authors: Wales Bruce A.
Published: April 2006

The north and south edges of a mature oak—hickory forest on the New Jersey Piedmont are characterized by local—scale vegetation gradients. These gradients are determined by both exposure—induced microclimatic influences and historical factors. The north edge has been relatively undisturbed since establishment. A narrow vegetative transition is associated with the relatively narrow microclimatic transition within the edge. A low thicket of tree growth (Cornus florida, Prunus avium, Viburnum prunifolium) mingled with woody vines and herbs is found exterior to the original edge. The old edge ends about 10 m within the forest and is characterized by increased densities and basal areas (compared to center) for Quercus spp. and Prunus avium. The original south edge is found about 20 m within the present forest. It is characterized by increased densities and basal areas of Quercus spp. and Viburnum prunifolium. Agricultural abandonment about 1900 accounts for reforestation in front of the old edge. The area immediately in front of the original edge is an open stand in which both Prunus avium and Viburnum prunifolium have increased densities. Exterior to this is a dense strip of medium—sized trees which is characterized by increased densities of Quercus spp. and Prunus avium. The remaining area is composed of small trees (Quercus velutina, Prunus avium) with clumps of woody vines between and upon them. The wide microclimatic transition at one time within the original south edge was transferred to the present edge with the development of a closed canopy within the reforested strip. Few edge effects are found now beyond 20 m within the stand. The segregation of species within and between the edges is more subtle than that between north and south slopes in the region. Species characterized by shade intolerance or good vegetative reproduction, or both, are prevalent at the edges. Many of these species also are associated with secondary succession in forest gaps, but edge responses are stronger than gap responses for most species. These include Fraxinus americana, Prunus avium, P. serotina, Sassafras albidum, and Viburnum prunifolium. Among canopy dominants Quercus velutina shows a stronger edge response than Q. alba or Q. rubra. Carya ovalis shows no significant edge response, whereas C. ovata displays a strong one. Relatively tolerant species such as Fagus grandifolia, Acer saccharum, and A. platanoides display no edge response. Most tree distributions are more localized than those of their reproductive size classes, presumably as a result of environmental selection acting upon seedlings and saplings within different forest microhabitats such as edges, gaps, and well—stratified areas of the stand. Although the techniques are different, this study represents a local—scale example of direct gradient analysis in that plots (amenable to analysis of variance) are used as micro—locational indices of the environmental complex and are matched to known microclimatic gradients.
Significance of Spider Predation in the Energy Dynamics of Forest‐Floor Arthropod Communities
Authors: Moulder B. C. , Reichle D. E.
Published: April 2006

Spiders were the most important entomophagous predators of a 137Cs—tagged Liriodendron tulipifera decomposer community. Radioisotope techniques were used to quantify the bioenergetic impact of spider predation on the forest—floor detritus food web. Temperature dependent 137Cs elimination by spiders and 137Cs concentrations in field animals were used in intake—loss equations to estimate ingestion by the spider population. Radiocesium body burdens fluctuated seasonally in response to litterfall and seasonal differences in temperature and precipitation. Ingestion rates, assimilation efficiencies, and respiratory energy losses were used to estimate gross and net production of the forest spider population. Annual mean population density of spiders was 126 individuals/m2. Population—density peaks occurred in fall, early winter, and summer. Mean biomass for the year was 43 mg dry wt/m2; maxima occurred in early winter and spring. Spiders 1—10 mg in size accounted for 59% of total biomass; spiders <1 mg or > 10 mg comprised the remaining 24% and 17% of the population, respectively. Predicted values for ingestion, assimilation, and respiration indicate that forest—floor spiders were active throughout a temperature range of 5°—20°C, with 13.3° the optimum for net production by spiders of all size classes. Spiders killed an equivalent of 2.08 kcal prey tissue/m2 per year and ingested 1.68 kcal/m2 per year. Respiratory energy loss equaled 1.23 kcal/m2 per year. Trophic level efficiencies calculated from seasonal energy—budget data were: (1) intake efficiency (prey killed/ingestion), 73—86%; (2) assimilation efficiency (assimilation/ingestion), 90—99%; (3) respiration efficiency (respiration/ingestion), 58—96%; (4) respiration/assimilation, 63—106%; (5) ecological growth efficiency (net production/ingestion), —5—34%; and (6) tissue—growth efficiency (net production/assimilation), —4—37%.
Role of Temperature and Water in the Ecology of Lungless Salamanders
Authors: Spotila James R.
Published: April 2006

Water economy and thermal relations of plethodontid salamanders were studied in the laboratory and in the field. Laboratory measurements included behavioral responses in temperature and relative humidity gradients, rates of dehydration and dehydration at various relative humidities and soil—moisture levels, and determination of critical thermal maxima by rapid controlled heating to a definite endpoint. Salamanders were acclimated to a combination of three temperatures and two photoperiods: 5°C, 16 hr of light alternating with 8 hr of darkness (LD 16:8); 5°C, (LD 8:16); 15°C (LD 16:8); 15°C (LD 8:16); 25°C (LD 16:8); and 25°C (LD 8:16). Three series of experiments were conducted on 20 populations representing 14 species. Critical thermal maximum increased with an increase in acclimation temperature indicating that the salamander's heat resistance was readily altered by its previous thermal history. Salamanders selected a definite range of temperatures and did not merely avoid extremes in the thermal gradient. Thermal preferenda were relatively stable for each species and were not significantly affected by either acclimation temperature or photoperiod. Rate of dehydration was dependent upon body size, drying power of the air, and ambient temperature. Interspecific differences in dehydration rates appeared to be related in part to differences in size. Species composed of small individuals lost weight faster than species made up of large individuals. As the vapor pressure deficit increased the dehydration rate increased. Dehydration was more rapid at higher temperatures. Rehydration rate increased as the percentage of weight loss due to dehydration increased and was more rapid at higher temperatures. Salamanders absorbed water from soil when soil—moisture tension was as high as 2.8 atm at 25°C. All species absorbed water from unsaturated soil at similar rates that were dependent upon soil—moisture content. Salamanders in the humidity gradient responded positively to differences in the moisture content of the air, and all but one species were more than 70% successful in selecting the highest relative humidity available in the gradient. Interspecific differences were apparent, but were not always correlated with habitat preferences. Plethodon glutinosus did not show any specific adaptation in its thermal responses or water relations that would account for its widespread distribution in the eastern United States. Plethodon ouachitae and P. caddoensis apparently have survived in the Ouachita Mountains due to favorable microhabitats and their ability to burrow deep beneath talus—covered slopes during hot and dry summers. Surface activity of P. caddoensis is limited in the summer by hot and dry conditions in its microhabitat.
Relationships of Environment to Composition, Structure, and Diversity of Forest Communities of the Central Western Cascades of Oregon
Authors: Zobel Donald B. , McKee Arthur , Hawk Glenn M. , Dyrness C. T.
Published: April 2006

Temperature and moisture stress of conifer saplings and needle nitrogen content of conifer saplings were measured at reference stands representing 16 forest communities in the central portion of the western Cascades province of Oregon. Most species occur over a wide range of temperature and moisture stress; many occupy a wider range of environments in the western Cascades than they do in the eastern Siskiyou Mountains of southwest Oregon. Differences between vegetation zones are reflected in a temperature index; within zones, communities are distinguished by moisture stress and, to a lesser extent, by temperature. In two cases vegetation differences appear to be related to low needle nitrogen contents. Use of complex gradients for vegetation ordination suggests certain environmental differences between communities which are contrary to the differences measured; therefore, we prefer the measured gradients over the complex gradients defined. Species diversity (the total number of vascular species) increases and dominance (Simpson's index) decreases away from moderate environmental conditions to warmer—drier and colder communities. Diversities of different strata are unrelated. Dominance is concentrated in fewer strata of the vegetation on the colder sites. However, discontinuities in the pattern of diversity with environment occur which are not related to major differences in our measured environmental indexes. Evergreenness of shrubs is highest in stands with the lowest foliar nitrogen levels.
Small Mammal Energetics in Grassland Ecosystems
Authors: French N. R. , Grant W. E. , Grodzinski W. , Swift D. M.
Published: April 2006

Results of quantitative sampling of small mammal populations at different grassland sites for a 3—yr period are compared to evaluate the energy requirements and consumption, according to trophic levels, for total small mammal communities at all seasons in different years. The purpose was to search for patterns of food utilization by these consumers at the different sites. This picture of the bioenergetics of small mammal populations over a wide range of grassland sites was constructed from extensive US/IBP Grassland Biome diet and population data and from physiological information out of the literature. The work represents one step in the process of understanding the role of consumers in the ecosystem. No species occurs at all sites and different trophic strategies predominate among the small mammals at each site: Microtines (herbivores) dominate the tallgrass prairie, sciurids (omnivores) dominate the northern shortgrass prairie, and heteromyids (granivores) dominate the bunchgrass and desert grasslands. Other groups occur at these sites and vary in their importance. At the tallgrass and midgrass sites the small mammal populations are largely dependent on herbage consumption, while at the northern and southern shortgrass prairie sites the rodent fauna is largely dependent on invertebrates. The most uniform distribution of resource utilization by this component of the consumer community occurs at the desert grassland site, where herbage, seeds, and animal matter are all utilized. Relative to the total amount of consumable herbage available (that actually utilized by the small mammal population), this resource is only slightly utilized (from a fraction to a few percent of available). Animal matter, largely invertebrates, is highly utilized at most sites and may in fact be a limiting factor on small mammal populations. The energy consumed by the small mammal population was greatest at the tallgrass prairie site, where the average annual consumption was 172 x 103 kcal/ha (= 720 MJ/ha). However, efficiency of biomass support was greatest at the northern shortgrass prairie site, where consumption of 32 x 103 kcal/ha (= 134 MJ/ha) supported proportionately more biomass (277 g live wt./ha) of animals than at the tallgrass site (935 g/ha). The estimates of population energy requirements presented here compare well with other available estimates. These results emphasize the great between year and site variability, however. Daily population respiration in summer may be as little as 14 and as large as 1,038 kcal°ha—1°day—1. Highest small mammal biomass occurred at the tallgrass (3,075 g live wt./ha) and the desert (2,304 g/ha) sites, and lowest at the midgrass (14 g/ha) site. Within the period of study, small mammal biomass was most stable at the southern shortgrass site and most variable at the tallgrass site. The role of small mammal populations in grassland ecosystem remains incompletely defined. A broader view of the total consumer community in relation to resources is required.
Role of Learning in Insect Parasitism
Authors: Taylor Robert J.
Published: April 2006

Several stochastic models of the process of parasitism, each incorporating learning in a different way, are developed. The clues the parasitoid learns to use to find its hosts are divided into two types, clues to individual hosts and clues to the host's habitat. The value of clues to the habitat can be a reflection of the spatial distribution of the hosts. The conclusions suggested by the experimental test of the models with the ichneumonid wasp Nemeritis canescens are that Nemeritis can learn to hunt its hosts in a novel environment;that a model postulating the learning of clues to the hosts fits better than a model postulating the learning of one: and that learning is potentially a stabilizing factor in the dynamics of host—parasite systems.
The Hubbard Brook Ecosystem Study: Composition and Dynamics of the Tree Stratum
Authors: Bormann F. H. , Siccama T. G. , Likens G. E. , Whittaker R. H.
Published: April 2006

The synecology of tree species was studied in a mature second—growth forest in the Hubbard Brook ecosystem. The forest, on a 13—ha undisturbed watershed ecosystem covering a 245—m range of elevation, has a basal area of about 23 m2ha—1. Dominance is shared by Acer saccharum, Fagus grandifolia, and Betula alleghaniensis. Direct gradient analysis and regression analysis indicated a strong response in both stand and species characteristics to an elevational complex gradient. Basal area per hectare, basal area per tree, deciduousness, and canopy height decreased with increasing elevation, whereas density, evergreenness, and species diversity increased. A lower rate of net primary productivity is correlated with higher elevations. Gradient analyses indicated that no two tree species have identical patterns of importance values over the elevational complex gradient. Sugar maple shows a decreasing trend; balsam fir, paper birch, and mountain ash show increasing trends. Beech, red spruce, mountain maple, and striped maple show intermediate patterns. Seedlings and saplings respond to the elevational gradient as do larger trees; however, the behavior of trees, seedlings, and saplings of the same species is clearly different. The Hubbard Brook ecosystem is located in relation to the vegetational zonation systems of earlier authors. The only generally agreed upon vegetational boundary, ca. 760 m (2,500 ft), is accounted for by a steepened rate of environmental change in the vicinity of that elevation. Various lines of evidence indicate that the present second—growth forest at Hubbard Brook approximates old—age mature northern hardwood forest. Therefore, the biogeochemical, productivity, and ecological data obtained from this study are representative of a mature ecosystem in dynamic balance with regional and local controlling factors, i.e., climate, geology, and topography.
Thermal Ecology of the Desert Dragon Amphibolurus inermis
Authors: Heatwole Harold
Published: April 2006

Amphibolurus inermis occurs throughout Australia except for the eastern third of the continent, the north—central coast, and the southwestern tip. It inhabits sandy soils. Body temperature rises in the morning, levels off and remains rather constant between 1000 and 1600 hr, and falls after 1600 hr. Thermoregulation involves changes in location and posture, color change, basking, burrowing, shade—seeking, and panting. The level of temperature maintained depends on geographic locality and immediate weather conditions and may depart widely from the temperature preferred in a laboratory gradient. The relative importance of specific behavioral responses varies with locality; burrowing and shade—seeking may be interchangeable. Amphibolurus inermis functions either as a thigmotherm or a heliotherm depending on local conditions and time of day. It is one of the most heat—resistant species known; the mean body temperature which causes loss of coordination is 48.5° C, and the lethal temperature is 49.3° C. Because of the extreme environments it occupies, A. inermis has narrow minimum thermal safety margins even though it has high temperature tolerances. Burrows tend to be located near thermoregulatory perches. When the sun—perch and the shade—perch are close together, an individual may have only one burrow; if the perches are further apart, a burrow will usually be located near each. If widely separated, auxiliary burrows may occur between the two types of perches. Burrows sometimes become too hot to serve in thermoregulation. Active individuals are found at all hours between sunrise and sunset in summer. However, individuals may seek shelter at midday. In winter the activity period is restricted to a few hours at midday. It is suggested that preferred temperatures may shift during the day, but that these levels cannot always be maintained. Head temperatures may be regulated more precisely than those of the body.
Microclimate, Fire, and Plant Production in an Illinois Prairie
Authors: Old Sylvia M.
Published: April 2006

Decomposition and effects of fire on microclimate and plant production of a Tall Grass Prairie were studied in east—central Illinois. After two years simulated litter samples in contact with soil lost 64% of their initial weight. Burning caused a 2—3 fold increase in production and a ten fold increase in flowering. Application of mulch, lowered flowering rate; response was proportional to thickness of mulch and length of time it was in place, Artificial shading of burned areas under green—house frames lowered flowering rate. Burning or clear cutting vegetation increased percent N and P in May foliage. A May application of N fertilizer increased flowering and dry matter production. Nutrient release from ash had no effect on flowering or production. Root production was similar on burned and Burn 3 areas; a turnover rate of 0.45 was calculated. Calcium content of roots in May increased after fire and N content decreased. Temperature from —5 to +50 cm and light intensity from 0 to +50 cm were higher on burned than Burn 3 areas. Maximum soil surface temperatures occurred three months earlier on Burn 0 than Burn 3 areas. Soil moisture was never severely limiting to plant growth. Growing season microclimate measurements at 50 and 200 cm were combined into a microclimatic index, which allowed comparison of the microenvironment of three burning regimes. Total flowering was proportional to duration and degree of favourable microclimatic conditions from May to mid July.
Advantages and Disadvantages of Bank Swallow (Riparia riparia) Coloniality
Authors: Hoogland John L. , Sherman Paul W.
Published: April 2006

We studied the advantages and disadvantages of Bank Swallow (Riparia riparia) coloniality in 1972 and 1973 by examining 54 colonies, ranging in size from 2 to 451 active nests, near Ann Arbor, Michigan USA. Four disadvantages were investigated: (1) increased competition for nest burrows and nest building materials, (2) increased competition for mates and matings, (3) increased possibilities of misdirected parental care because of either brood parasitism or the mixing up of unrelated young, and (4) increased transmission of ectoparasites. Physical interference in reproductive functions and the possibility of intraspecific killing of offspring were also considered. The intensity of the various forms of competition increased with increasing colony size, though not always directly. Flea infestation also increased with increasing colony size. Intraspecific brood parasitism was not observed, and parent Bank Swallows began discriminating between their own and unrelated offspring at the time when the young first began to mix. Three hypotheses to explain the maintenance of coloniality were tested: (1) shortage of suitable nesting habitats, (2) advantages associated with social foraging, and (3) reduced predation on adults, young, or eggs. Shortage of suitable habitat could not be demonstrated. Parents did not appear to feed in groups, and survivorship of nestlings during cold weather and weight of nestlings at 10 days of age both suggested that competition for food increased with increasing colony size. Although there was no relationship between colony size and amount of nocturnal predation, adult birds mobbed diurnal predators. Using a stuffed weasel, we studied such mobbing responses. Our data suggest that diurnal predators at larger colonies are (1) detected more quickly, (2) mobbed by greater numbers of birds, and (3) subjected to more vocal commotion than are predators at smaller colonies. Further, we demonstrated that mobbing is at least sometimes effective in deterring avian predators. We suggest that reduced predation on eggs and young, resulting from both group defense and "selfish herd" effects, is an important advantage of Bank Swallow coloniality.
Forest Overstory Vegetation and Environment on the Missouri River Floodplain in North Dakota
Authors: Johnson W. Carter , Burgess Robert L. , Keammerer Warren R.
Published: April 2006

The study area, bounded north and south by two large reservoirs, includes the most extensive remnant of floodplain forest in the Dakotas. Structure and composition of the forest overstory are strongly related to stand age and horizontal and vertical position on the floodplain. Populus deltoides Marsh. and Salix amygdaloides Anders. predominate in young stands which generally occur on low terraces near the center of the floodplain. Fraxinus pennsylvanica var. lanceolata (Borkh.) Sarg., Acer negundo L., Ulmus americana L., and Quercus macrocarpa Michx., which replace Populus and Salix through time, predominate in old stands on high terraces near the edge of the floodplain. Stands intermediate in composition are uncommon because of the discontinuous meandering pattern of the river across its floodplain. Surface soil environment and species diversity change markedly during the course of succession. The soils of young stands are generally sandy and low in organic matter. Soil nutrient content and available water capacity are generally higher in older stands because of higher organic matter content and repeated inputs of nutrient—rich silt from past floods. Tree species diversity (H') initially increases as stands age, reaches a maximum in stands with mixtures of both pioneer and terminal species, and declines slightly in the oldest stands. Both variety and evenness follow a similar pattern. Analyses of population structure indicate a recent decline in the establishment of small stems of Acer and Ulmus. Tree core analyses show a similar decline in diameter growth rate for Acer, Ulmus, and Fraxinus. Available data suggest that these changes can be attributed to the removal of periodic spring flooding caused by the presence and operation of the reservoirs. It is also hypothesized that the lack of seedling—sapling stands of Populus in the region is the result of a presumed reduction in the meandering rate of the river following reservoir construction and poor seedbed conditions in the absence of flooding.
Structure and Function of Successional Vascular Plant Communities in Central New York
Authors: Mellinger Michael V. , McNaughton S. J.
Published: April 2006

Succession of vascular plant communities was studied on fields in central New York abandoned for the previous 4 to 36 yr. Changes within fields as they aged were consistent with the overall pattern of change between fields. Over the period covered, Phleum pratense was replaced successively as the major species by Solidago altissima, Picris hieracioides, and Cornus racemosa. Succession was accompanied by increased biological diversity, reduced dominance, decreased energy flow per unit biomass, and increased stability to a pulse perturbation of inorganic nutrients. Although soil phosphorus is an important factor influencing community function on the fields studied, the fertilization experiment indicated a fundamental reorganization of community relationships during succession which reduces community responsiveness to fluctuations in soil nutrients. Increased diversity resulted from the partitioning of constant density and net productivity among increasing numbers of species. Accompanying the increase in diversity was decreasing seasonal synchrony of resource demands among the constituent species pool. Although successional stages could be arbitrarily recognized by the taxonomic identification and growth forms of dominant species, there was a gradual and continuous change in structural and functional properties of the plant community, and no objectively definable stages could be delimited. These studies indicate that a failure to determine productivities of individual species may seriously distort the evaluation of community properties.
Influence of Effluents from a Zinc Factory on Lichens
Authors: Nash Thomas H.
Published: April 2006

Lichen species richness and abundance are reduced by approximately 90% in lichen communities near a zinc smelter at Lehigh Water Gap in comparison with the lichen communities of Delaware Water Gap. The principal cause of the impoverished lichen flora in the Lehigh Water Gap area is probably high concentrations of zinc. Of the non—pollution and pollution factors considered, only abnormal soil concentrations of zinc and cadmium extend beyond the limits of the lichen impoverishment zone. Because Zn is present in concentrations generally 100 times higher than that of Cd and because Cd is experimentally shown to be no more toxic to lichens than is Zn, it is probable that Zn is the more important, detrimental factor to lichens in the Palmerton area. Near the smelters, Zn, Cd and sulfur dioxide are all present in sufficiently high concentrations to be detrimental to lichen growth and survival. However, at the perimeter of the lichen—impoverished zone, only Zn is present in high enough concentrations to be phytotoxic. Although microclimatic alteration in forested areas near Palmerton may be sufficiently great to be a stress for a few lichen species that are adapted to shaded conditions, no microclimatic differences were demonstrable between Delaware and Lehigh Water Gaps for open habitats where most lichen species normally occur in this area. Variations in such factors as lichen geographical range, climate, substrate composition and abundance, and fire history are probably of negligible importance in explaining the reduction in lichen numbers or abundance in Lehigh Water Gap.
A Predator‐Prey System in the Marine Intertidal Region. I. Balanus glandula and Several Predatory Species of Thais
Authors: Connell Joseph H.
Published: April 2006

On San Juan Island, Washington, three species of intertidal barnacles (Balanus glandula, Balanus cariosus and Chthamalus fissus) are the main prey of several species of predators, the commonest being three species of snails, Thais emarginata, Thais canaliculata and Thais lamellosa. Larvae of B. glandula settle throughout the intertidal zone but, except in quiet bays, survive to maturity only in a narrow zone at the top of the shore. In quiet bays, where predators of barnacles were scarce, and in areas of turbulent water where predators were excluded by other circumstances, adult B. glandula occurred over the whole intertidal zone. From the lower part of the intertidal zone. Predators were evidently eliminating all B. glandula from the lower part of the intertidal zone. The rates of feeding of Thais lamellosa and Thais emarginata were measured in cages on the shore. The existing population of Thais could account for all of the mortality of B. glandula which occurred at low shore levels in mid and late summer. By late autumn these predators could eat all the remaining B. glandula of that year's settlement at low levels, but at upper shore levels the Thais population could not account for all the mortality of B. glandula in summer. The Thais populations shift upwards from the lower shore levels in the autumn and it is very probable that this increased predation is enough to eliminate the barnacles at the middle and upper shore within the next year. The recruitment of B. glandula every year was quite regular. The breeding population in the narrow "refuge" zone at the top of the intertidal zone was capable of replacing itself as well as colonizing the middle and lower shore. The settlement below the refuge zone can be regarded simply as a regular food supply for the predator population. Because of the dependability of this food supply at upper shore levels, a predator, T. emarginata, has evolved to specialize at these upper levels. In Scotland, where the recruitment of barnacles is irregular, no such specialization is possible. Thus at least two species of predators are supported at different shore levels at San Juan Island, whereas only one species occupies the whole intertidal shore in Scotland. In Scotland, much of the mortality of young barnacles was caused by intraspecific crowding in dense populations, and these deaths provide food for scavengers, rather than predators. In contrast, at San Juan Island of the mortality of young barnacles is caused by predators. Thus the predators at San Juan Island are more efficient than those in Scotland, since they eat a much higher proportion of the available prey. Whereas in Scotland the distribution and abundance of barnacles is largely determined by competition for space, at San Juan Island the barnacles is largely determined by competition for space, at San Juan Island the barnacles are limited by predation.
Spatial and Temporal Variation in Costa Rican Fruit and Fruit‐Eating Bird Abundance
Authors: Levey Douglas J.
Published: April 2006

Understory fruit and fruit—eating birds were censused monthly for a year in gaps, intact forest, and second—growth sites of a lowland Costa Rican rain forest. Both fruits and birds displayed significant seasonal variation. Peak fruit abundance corresponded with peak fruit—eating bird abundance. Fruits were most abundant in the mid—to—late rainy season (August—January). Crop sizes were larger on second—growth plants than on either gap or intact forest plants. Also, fruit was much more common in second growth than in gaps and more common in gaps than in intact forest. Fruit—eating birds followed the same general patterns of spatial and temporal variation. They were significantly most abundant in second growth, significantly least abundant in intact forest, and most common from October to January. A large increase in the frugivore population in October was due to an influx of temperate and altitudinal migrants. In addition, populations of some resident frugivore species increased concurrently, suggesting altitudinal migration in some of these species as well. The two most common understory frugivores molted during the period of fruit high and bred during the period of fruit low. I suggest that insect abundance may be more important than fruit abundance in determining breeding cycles of these birds. Given the extent of spatial and temporal variation in fruit and frugivore abundance, and the apparent tracking of fruit resources by birds, large areas of diverse habitats are probably necessary for the long—term maintenance of frugivore populations.