bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pollination intensity and paternity in flowering plants
Authors: Christopher Dorothy A , Mitchell Randall J , Karron Jeffrey D 
Published: October 2019

AbstractBackgroundSiring success plays a key role in plant evolution and reproductive ecology, and variation among individuals creates an opportunity for selection to act. Differences in male reproductive success can be caused by processes that occur during two stages, the pollination and post-pollination phases of reproduction. In the pollination phase, heritable variation in floral traits and floral display affect pollinator visitation patterns, which in turn affect variation among plants in the amount of pollen exported and deposited on recipient stigmas. In the post-pollination phase, differences among individuals in pollen grain germination success and pollen tube growth may cause realized paternity to differ from patterns of pollen receipt. The maternal plant can also preferentially provision some developing seeds or fruits to further alter variation in siring success.ScopeIn this review, we describe studies that advance our understanding of the dynamics of the pollination and post-pollination phases, focusing on how variation in male fitness changes in response to pollen limitation. We then explore the interplay between pollination and post-pollination success, and how these processes respond to ecological factors such as pollination intensity. We also identify pressing questions at the intersection of pollination and paternity and describe novel experimental approaches to elucidate the relative importance of pollination and post-pollination factors in determining male reproductive success.ConclusionsThe relative contribution of pollination and post-pollination processes to variation in male reproductive success may not be constant, but rather may vary with pollination intensity. Studies that quantify the effects of pollination and post-pollination phases in concert will be especially valuable as they will enable researchers to more fully understand the ecological conditions influencing male reproductive success.
Predicting Public Interest in Nonsurgical Cosmetic Procedures Using Google Trends
Authors: Tijerina Jonathan D , Morrison Shane D , Nolan Ian T , Parham Matthew J , Nazerali Rahim 
Published: October 2019

Abstract

Background
Google Trends (GT) provides cost-free, customizable analyses of search traffic for specified terms entered into Google’s search engine. GT may inform plastic surgery marketing decisions and resource allocation.

Objectives
The aim of this study was to determine GT’s utility in tracking and predicting public interest in nonsurgical cosmetic procedures and to examine trends over time of public interest in nonsurgical procedures.

Methods
GT search volume for terms in 6 ASPS and ASAPS nonsurgical procedure categories (Botox injections, chemical peel, laser hair removal, laser skin resurfacing, microdermabrasion and soft tissue fillers [subcategories: collagen, fat, and hyaluronic acid]) were compared with ASPS and ASAPS case volumes for available dates between January 2004 and March 2019 with the use of univariate linear regression, taking P &lt; 0.01 as the cutoff for significance.

Results
Total search volume varied by search term within the United States and internationally. Significant positive correlations were demonstrated for 17 GT terms in all 6 ASPS and ASAPS categories: “Botox®,” “collagen injections,” “collagen lip injections” with both databases; and “chemical skin peel,” “skin peel,” “acne scar treatment,” “CO2 laser treatment,” “dermabrasion,” “collagen injections,” “collagen lip injections,” “fat transfer,” “hyaluronic acid fillers,” “hyaluronic acid injection,” “hyaluronic acid injections,” “Juvederm®,” and “fat transfer” with just 1 database. Many search terms were not significant, emphasizing the need for careful selection of search terms.

Conclusions
Our analysis further elaborates on recent characterization of GT as a powerful and intuitive data set for plastic surgeons, with the potential to accurately gauge global and national interest in topics and procedures related to nonsurgical cosmetic procedures.
The Function of Singing in Female Black-Headed Grosbeaks (Pheucticus melanocephalus): Family-Group Maintenance
Authors: Ritchison Gary 
Published: September 2019

Abstract
The responses of young Black-headed Grosbeaks (Pheucticus melanocephalus) to playback of the songs of parents and strangers were examined. I found that young grosbeaks moved about more, called more, and were more often oriented toward speakers in response to parental song (both male and female) than in response to the songs of strangers. I suggest that such a response is part of a system used by Black-headed Grosbeaks to maintain family groups after the young fledge. In this system, an adult with food, but unaware of the location of its young, sings to elicit begging from its young. The parent bird is then able to locate and feed its young.
Adaptations of the Gray Catbird Dumetella carolinensis to Long Distance Migration: Energy Stores and Substrate Concentrations in Plasma
Authors: Marsh Richard L. 
Published: October 2019

Abstract
The major body components (water, lean dry, and fat) were measured in the carcasses of Gray Catbirds from which the flight muscles had been removed. Birds were collected from May through October near Ann Arbor, Michigan and during September and October near Gainesville, Florida. Additionally, the glycogen content of muscle and liver and the concentrations of glucose and triglycerides in plasma were determined in catbirds sampled during fall migration in Florida. Catbirds attained maximum body masses of ∼50 g in Florida, largely due to the addition of fat. Relatively lean birds (∼3-4% body fat) in spring through fall weighed approximately 35 g. Thirteen percent of the birds sampled were estimated to have had sufficient reserves of fat to cross the Gulf of Mexico, although a larger proportion of the population probably makes this crossing. The lean dry mass of the carcass (without the flight muscles) is related significantly to structural body size and time of day, but is not related to molt, sex, or carcass fat content. Plasma glucose and triglycerides in free-living fall migrants do not vary diurnally. Liver glycogen, however, is four times higher in the evening than in the morning (77 and 19 mg/g, respectively), and muscle glycogen is five times higher in the evening (20 and 4 mg/g, respectively). Evening concentrations of glycogen are among the highest values reported for birds and do not confirm the reduction in glycogen reported for some other migrants.
Behavior, Morphology, and Systematics of Sirystes sibilator (Tyrannidae)
Authors: Lanyon Wesley E. , Fitzpatrick John W. 
Published: October 2019

Abstract
Field and laboratory studies support recent hypotheses that Sirystes sibilator is closely allied with the myiarchine flycatchers rather than with Tyrannus or with the cotingids. The first confirmed nest of this tyrant (located in a natural tree cavity), its foraging behavior, and the derived character states of the nasal septum and of the syrinx argue convincingly for its placement in an assemblage with Myiarchus, Rhytipterna, and Casiornis. Data, still lacking, on the color of the eggs and nature of the nest lining are needed for Sirystes (and for Rhytipterna and Casiornis) before consideration can be given to the generic relationships within the myiarchine flycatchers.
The Pallid Falcon Falco kreyenborgi Is a Color Phase of the Austral Peregrine Falcon (Falco peregrinus cassini)
Authors: Ellis David H. , Garat Cesar Peres 
Published: September 2019

Abstract
The Pallid Falcon (Falco kreyenborgi), a rare form from southern Patagonia and Tierra del Fuego, has, since its discovery in 1925, gained acceptance as a full species. In 1981, we observed 13 Pallid Falcons on the Patagonian Steppe. Four adult Pallid Falcons were paired with normal Peregrine Falcon (Falco peregrinus cassini) mates. Two normal-phased peregrine pairs produced mixed broods of normal and pallid young. One pair of pallid adults produced only pallid young. These observations lead to the conclusion that the Pallid Falcon is conspecific with and a color phase of the Peregrine Falcon.
Brown Pelican Foraging Success and Kleptoparasitism by Laughing Gulls
Authors: Schnell Gary D. , Woods Barbara L. , Ploger Bonnie J. 
Published: October 2019

Abstract
Previous studies have shown age-related differences in feeding success for a number of bird species, particularly those found in marine environments. We compared the foraging success of adult and immature Brown Pelicans (Pelecanus occidentalis) feeding along the Playa Miramar northwest of Manzanillo, Colima, Mexico. On many of the feeding dives, Laughing Gulls (Larus atricilla) were attracted to pelicans and often behaved aggressively in attempts to obtain food from them. Adult Brown Pelicans were significantly more successful than immatures. Laughing Gulls were attracted to successful pelicans regardless of the age of the pelican. The proportion of unsuccessful immature pelicans not attracting gulls was higher than that of unsuccessful adult pelicans. Particularly inept immature pelicans are probably easily identified by gulls and ignored completely. Although we found no differences in the frequency of pelican-gull physical contact (which we used as a measure of gull aggressiveness) between immature and adult pelicans, such behavior was directed almost exclusively toward successful pelicans. Gull aggression was also more intense when pelicans were attacked by groups of gulls.
On the Use of Avian Mortality Patterns to Test Sexual Selection Theory
Authors: Weatherhead Patrick J. , Greenwood Hamilton , Clark Robert G. 
Published: October 2019

Abstract
To test the hypothesis that reduced survival of large males limits the extent to which sexual selection can increase male size, we examined mortality patterns in Redwinged Blackbirds (Agelaius phoeniceus) subjected to a surfactant spray. Univariate comparisons of wing measurements did not support the predicted mortality patterns. Although principal component analysis revealed that mortality was nonrandom with respect to some morphological characters, there was again no evidence of the predicted patterns either of directional selection favoring smaller males or of stabilizing selection favoring intermediatesized females. This result led us to recognize that, like previous authors, we had made the incorrect assumption that large males should be more vulnerable to all mortality factors rather than the correct interpretation of the theory, that differential mortality should be seen as the net effect of all mortality factors. Only two published data sets are appropriate for testing the hypothesis, and neither shows differential mortality amongst males on the basis of size.
Reproductive Energetics of Two Tropical Bird Species
Authors: Bryant D. M. , Hails C. J. , Tatner P. 
Published: October 2019

Abstract
Daily energy expenditure (DEE) during breeding was studied in Pacific Swallows (Hirundo tahitica) and Blue-throated Bee-eaters (Merops viridis) in Malaysia. DEE was measured directly by the doubly labelled water (D218O) technique and indirectly by TAL (time-activity-laboratory) methods during the time adults were feeding their young at the nest. DEE was 76.6 kJ/day in the Pacific Swallow and 77.4 kJ/day in the larger Blue-throated Bee-eater (D218O results). The relatively low DEE, compared to temperate-zone insectivores that also feed in flight, was attributed to the action of proximate factors, namely a more favorable thermal environment and shorter days (which results in less daytime activity). In bee-eaters, partial use of a low-cost foraging technique also contributed to their lower DEE. The suitability of DEE as a measure of reproductive effort is discussed.
Must Desert Chukars (Alectoris chukar sinaica) Drink Water? Water Influx and Body Mass Changes in Response to Dietary Water Content
Authors: Degen A. Allan , Pinshow Berry , Shaw Peter J. 
Published: October 2019

Abstract
The Chukar subspecies Alectoris chukar sinaica inhabits the Negev desert, which is characterized by hot, dry summers, and little winter rainfall. Vegetation is dry and dormant during the summer and autumn; green, succulent vegetation is available following winter rain. We studied whether or not and under what dietary conditions Chukars require drinking water. Four groups of Chukars in an outdoor aviary received either a dry ration + water, a dry ration + green vegetation, a dry ration + green vegetation + water, or green vegetation only.
The birds offered only greens lost 15% of their body mass in the first 8 days and 2.9% over the next 6 days, while birds on the other three treatments maintained body mass. The birds receiving only greens had the highest total body water to body mass ratio and the highest water influx. We concluded that the Chukars receiving only green vegetation met their water requirements but not their maintenance energy requirements. Chukars fulfilled both their water and energy requirements on a dry ration + green vegetation (without drinking water); the green vegetation comprised approximately 60% of their total fresh matter intake, or 26% of their total dry matter intake. Our analysis suggests that wild desert Chukars do not require drinking water from early winter to late spring, when succulent forage is available, but probably need free water during summer and autumn, when the bulk of their diet is seeds.
Karyotypic Evolution and Long-Term Effective Population Sizes of Birds
Authors: Barrowclough George F. , Shields Gerald F. 
Published: October 2019

Abstract
Rates of karyotypic change in birds are used to estimate that, over the longterm history of a wide assortment of genera, avian effective population sizes have averaged on the order of 100. This result is consistent with the results of electrophoretic studies of geographic variation of allelic frequencies within species but is somewhat less consistent with the results obtained from demographic modeling. Three methodologically independent analyses have now corroborated the hypothesis that avian effective population sizes are typically of the order of 102 or larger.
Daily Energy Expenditure of Savannah Sparrows: Comparison of Time-Energy Budget and Doubly-Labeled Water Estimates
Authors: Williams Joseph B. , Nagy Kenneth A. 
Published: October 2019

Abstract
Using the doubly-labeled water (DLW) technique, we measured the CO2 production of six free-living male Savannah Sparrows (Passerculus sandwichensis, mean mass 19.1 g) and found a mean (Â±1 SD) of 7.28 Â± 1.36 ml ${\rm CO}_{2}/{\rm h}$. Assuming an R.Q. of 0.85 and 24 J/ml CO2, we calculated a mean $\dot{H}_{TD}$ (daily energy expenditure) of 80.3 Â± 16.6 kJ/day. Simultaneously to our DLW measurements, we constructed time budgets for the sparrows during their normal activities with the intent of exploring the agreement between predictions of a number of time-energy budget (TEB) models from the literature and DLW measurements. Our results reveal that several models yield reasonable results, the mean value for the models of Kendeigh et al. (1977), Walsberg (1977), and Mugaas and King (1981) differing from DLW measurements by only +4.7, -5.6%, and +5.7%, respectively. Comparisons of $\dot{H}_{TD}$ as predicted by these TEB models between species and within species between nesting phases might be made with some confidence. However, the variation in TEB estimates is not related to variation in DLW measurements within our study. This precludes statements about differences between individuals.
Nutrient Reserve Dynamics of Breeding and Molting Brant
Authors: Ankney C. Davison 
Published: October 2019

Abstract
I collected 150 Brant (Branta bernicla) at East Bay, Southampton Island, Northwest Territories, Canada, in 1979 and 1980 to evaluate how much these birds rely on reserves of fat, protein, and calcium during egg production, incubation, and the subsequent wing molt. Egg laying resulted in decreases in body weight and nutrient reserves of females. These decreases could have accounted for all of the fat but only 70% of the protein in an average clutch. Neither males nor females had sufficient reserves when incubation began to enable them to fast during that period. Only 11% and 22% of the energy required by males and females, respectively, could have been derived from their reserves during incubation. Brant evidently did not use body reserves to obtain nutrients for feather growth during wing molt. Rather, molting males and females accumulated muscle protein, which supports my hypothesis that wing molt is not a nutritional stress for waterfowl.
Foraging Success and Tree Species Use in the Least Flycatcher
Authors: Rogers Christopher M. 
Published: October 2019

Abstract
I examined the effect of tree species morphology on foraging behavior in a hover-gleaning bird species, the Least Flycatcher (Empidonax minimus). Birds in four breeding territories in northern Wisconsin displayed nonsignificant differences in an index of foraging success (S) among four tree species of divergent morphology. However, significant variation in S occurred among the three tree species common to all four territories; in addition, multiple comparisons indicated that S values in Betula papyrifera were significantly greater than those in Acer spp. or Quercus spp. Despite its statistical significance, variation in S was not large, and flycatchers used available tree species in general accordance with their abundances. No significant correlation was found between S and tree species use. These results are not immediately consistent with an emerging perspective of avian community structure that predicts that hover-gleaners, unlike gleaners, should be affected little by foliage morphology. Foraging efficiency and prey depletion in initially favored tree species are proximate factors possibly linked to breadth of tree species use.
Nesting Success and Mortality of the Boat-Tailed Grackle
Authors: Bancroft G. Thomas 
Published: October 2019

Abstract
Of 605 Boat-tailed Grackle (Quiscalus major) nests with complete clutches, 60.5% fledged young. Survival of nests to the hatching stage averaged 78.7%, and survival from hatching to fledging averaged 76.9%. Nesting success between localities varied from none to almost all nests fledging some young. Fledging success for 3-egg clutches averaged 64.8% and was significantly higher than the 50.8% success rate that 2-egg clutches averaged. Individual survival of eggs from laying through hatching was lower in 2-egg clutches than in 3-egg clutches, but from hatching to fledging nestling survival was higher. Thus, in contrast to nest survival, equal proportions of eggs in 2- and 3-egg clutches produced fledglings.
Predation was the greatest source of mortality, with predators taking 14.8% of the 1,605 eggs and 13.1% of the 1,145 nestlings. Of eggs that survived to the hatching stage, 9.2% failed to hatch. Starvation (13.4%) was the most common source of nestling mortality. Nest abandonment accounted for the death of 5.7% of the eggs and 2.9% of the young. The sources of mortality varied spatially and temporally in an unpredictable way. This uncertainty has resulted in the flexible nesting biology of grackles.
Old Age and Breeding Behavior in a Tropical Passerine Bird Ploceus cucullatus under Controlled Conditions
Authors: Collias N. E. , Collias E. C. , Jacobs C. H. , Cox C. R. , McAlary F. A. 
Published: October 2019

Abstract
Many tropical species of passerine birds have potentially long reproductive lives in both nature and aviaries, but rate of breeding by old individuals may eventually decline. A group of individually color-banded African Village Weavers (Ploceus cucullatus), a polygynous species, was kept in aviaries at Los Angeles for 22 years. At 14-18 years of age, old males built significantly fewer nests per year, displayed to females less often, had fewer mates, and generally fathered fewer clutches than did the same males when 9-13 years old. One male reached 24 years of age, when he rarely sang and no longer wove when provided with nest materials. The females, after reaching "middle age" (9-13 yr), laid significantly fewer eggs per year, and still fewer during "old age" (14-18 yr). When 14 or more years old, weavers of both sexes rested much more than did young adults 4-6 years old in the same aviary.
Individuals differed greatly in the decline of breeding behavior with age. Some individual Village Weavers bred at a surprisingly great age for passerine birds, e.g. fertile copulations by one 19-year-old male and by one 18-year-old female. These seem to be the oldest breeding ages yet recorded for any small passerine bird. Long reproductive life of a small number of individuals that contribute disproportionately to the next generation would give a selection pressure for longevity, and also could help explain the evolution of small clutch size (2-3 eggs) in the Village Weaver and in many other tropical birds.
Energy Metabolism in the Locomotor Muscles of the Common Murre (Uria aalge) and the Atlantic Puffin (Fratercula arctica)
Authors: Davis M. Benjamin , Guderley Helga 
Published: October 2019

Abstract
To compare the metabolic systems that support the combination of flying and diving with those used to support burst flying and sustained flying, myoglobin concentrations and maximum enzyme activities were determined for selected enzymes of glycolysis, the Krebs cycle, and amino acid metabolism in the pectoral, supracoracoideus, and sartorius muscles of the Common Murre (Uria aalge), Atlantic Puffin (Fratercula arctica), Rock Dove (Columba livia; hereafter "pigeon"), and Ring-necked Pheasant (Phasianus colchicus). Glycolytic enzyme levels in the flight muscles were lower in the murre and the puffin than in the pheasant, while both glycolytic and Krebs-cycle enzyme levels resembled those in the pigeon. We believe puffins and murres do not rely extensively on anaerobic glycolysis during diving. In concordance with a role in oxygen storage for diving, the levels of myoglobin in the flight muscles of murres and puffins were higher than those in pigeons or pheasants. They were lower than published values for penguins, however. In contrast to the trends for pigeon and pheasant muscles, the alcid sartorius muscles had a considerably lower aerobic orientation than the flight muscles.
Dispersal Patterns of Western Gulls from Southeast Farallon Island
Authors: Spear Larry B. 
Published: September 2019

Abstract
During 1978-1981 I studied age- and sex-related dispersal and foraging patterns of Western Gulls (Larus occidentalis) that breed on Southeast Farallon Island, California. Most adults were sedentary and foraged primarily on oceanic food during all seasons except autumn, when human refuse was of major importance. Autumn was the only period when adults did not maintain breeding territories, and also the time of primary molt when flight capabilities were reduced. During the breeding season many subadults moved north to areas where oceanic productivity is high. During autumn/winter most moved south to the Gulf of the Farallons/San Francisco Bay Area, where birds ate both oceanic food and refuse. Dispersal patterns of first-year gulls varied markedly between years, apparently as a result of annual differences in oceanic productivity. The consistency of movement patterns of other age classes resulted from an age-related increase in fidelity to foraging locations. This was most pronounced in adults. Most adults dispersed each year to the same site, and minimized competition by reducing concentrations at each location. Males were more sedentary than females, probably because they are responsible for securing and holding breeding territories.