A Comparative Study of the Reproductive Biology of Sympatric Morning Glories (\u3cem\u3eIpomoea\u3c/em\u3e-convolvulaceae)

Despite the astounding diversity of flowering plants and of mobile organisms that serve as pollinators, sympatric co-flowering plants can potentially share pollinators with each other. This places two selection pressures on plants. First, plants compete for pollinators to visit their flowers and secondly, entice pollinators to be faithful (specialized) and visit only other members of their species. I tested whether sympatric co-flowering plants reduced their selection pressures via temporal partitioning or differential attraction of pollinators using six closely related, sympatric co-flowering morning glories (Ipomoea-Convolvulaceae). Diurnal flower phenology tightly overlapped, which did not facilitate temporal partitioning of pollinators. However, the differences in corolla color and shape allowed for predictions of differential attraction of pollinators among the six Ipomoea flowers examined based on the pollination syndrome concept. Despite the recent caveats raised about the lack of rigorous fit between floral traits and pollinator fauna over large floras, the pollination syndrome concept adequately explained pollinator preferences in Ipomoea. As predicted, bees visited bee flowers (/. hederacea, I. imperati, I. pandurata, and I. trichocnrpa), and hummingbirds and butterflies visited their respective flowers (/. hederifolia and /. quamoclit). Nectar, as predicted by the pollination syndrome concept, was of smaller volume and more concentrated in the bee flowers compared to bird flowers. Overall, bee flowers also receive much of their stigmatic pollen loads from pollen deposition by bees, whereas bird flowers received most of their stigmatic pollen loads through autogamy. Fruit and seed set were larger in bird flowers, and generally, all species had higher fruit and seed sets in 2000. Although pollination syndromes may not adequately predict the pollinator fauna of all plants, within the Ipomoea model examined here pollination syndromes accurately explained pollinator preferences

Orbital Solutions and Absolute Elements of the Eclipsing Binary MY Cygni

Differential UBV photoelectric photometry for the eclipsing binary MY Cyg is presented. The Wilson-Devinney program is used to simultaneously solve the three light curves together with previously published radial velocities. A comparison is made with the previous solution found with the Russell-Merrill method. We examine the long-term apsidal motion of this well-detached, slightly eccentric system. We determine absolute dimensions, discuss metallicity/Am-star issues, and estimate the evolutionary status of the stars

HD 126516: A Triple System Containing a Short-period Eclipsing Binary

From numerous radial velocities as well as Johnson B and V differential photoelectric photometry, we have determined the orbital elements and other properties of the single-lined triple system HD 126516. This system consists of a narrow-lined F5 V star and an unseen M dwarf companion in a 2.1241 day circular orbit. The small, low-mass secondary produces detectable eclipses of the primary, and that pair has been given the variable star name V349 Vir. Variations of the center-of-mass velocity of this short-period system have an orbital period of 702.7 days or 1.92 yr and an eccentricity of 0.36. The third star is likely a K or M dwarf. From an analysis of our photometry, we conclude that the primary of HD 126516 is not a γ Dor variable. Comparison with evolutionary tracks indicates that the primary is slightly metal-poor and has an age of 2.5 Gyr. The projected rotational velocity of the primary is very low, just 4 km s−1, which is 10 times less than its synchronous rotational velocity. Thus, either that component\u27s rotation is extremely non-synchronous or the inclinations of the rotational and orbital axes are very different, and so the primary has a very large spin–orbit misalignment. Because of the moderate age of the system and the fact that its orbit is already circularized, neither situation is expected theoretically

Evolution of the Starspots in V478 Lyrae from 1980 to 1988

Differential UBV photometry of V478 Lyrae from 1980 to 1988 is given and analyzed as 22 separate light curves, each spanning an average of a dozen rotation cycles. It is shown that spots on V478 Lyr appear to have lifetimes on the order of several months to a year. The amplitude of the light loss produced by a spot can change by a factor of 2 within 20 days. In the only four determinate cases, a spot came into existence at one of the two conjunctions, that is, in the middle of the hemisphere facing (or opposing) the companion star. This finding provides additional support for the picture of a four-sector longitudinal structure, aligned with the major axis of the binary, which determines where magnetically active regions develop

Absolute Properties of the Eclipsing Binary VV Corvi

We have obtained red-wavelength spectroscopy and Johnson B and V differential photoelectric photometry of the eclipsing binary VV Crv = HR 4821. The system is the secondary of the common proper motion double star ADS 8627, which has a separation of 52. VV Crv has an orbital period of 3.144536 days and a low but non-zero eccentricity of 0.085. With the Wilson–Devinney program we have determined a simultaneous solution of our spectroscopic and photometric observations. Those orbital elements produce masses of M1 = 1.978 ± 0.010 M☉ and M2 = 1.513 ± 0.008 M☉, and radii of R1 = 3.375 ± 0.010 R☉ and R2 = 1.650 ± 0.008 R☉ for the primary and secondary, respectively. The effective temperatures of the two components are 6500 K (fixed) and 6638 K, so the star we call the primary is the more massive but cooler and larger component. A comparison with evolutionary tracks indicates that the components are metal rich with [Fe/H] = 0.3, and the system has an age of 1.2 Gyr. The primary is near the end of its main-sequence lifetime and is rotating significantly faster than its pseudosynchronous velocity. The secondary is still well ensconced on the main sequence and is rotating more slowly than its pseudosynchronous rate

Pen is Mightier Than the Six-Shooter: Western Symbolism in the New York Newspaper Writings of Former Gunfighter Bat Masterson

Bat Masterson, once one of the most feared gunfighters in the American West, died not with a six-shooter in his hand but with perhaps a more powerful weapon - the pen. Although best known in history as a colorful lawman and gambler in the untamed boom towns of the frontier, Masterson spent the last two decades of his life as a New York newspaper reporter and sports editor. This hero of the West, who owed his fame in great part to the newspaper writings of his exploits on the frontier, in the latter part of his life was himself a journalist, chronicling the exploits not of gunfighters and desperadoes but of some of the most famous athletes of the early twentieth century. As a newspaper columnist, Masterson had a greater forum for his views and more influence than he ever did as a lawman or gunfighter. While it is significant to examine why a former gunfighter was given such a platform, it is of greater importance to study how he used this forum and what his writings can tell us about that period of American history from the final days of the frontier in the late nineteenth century to the urbanization of America that continued through the time of Masterson's death in 1921. The attempt to understand the how and what of Masterson's newspaper writings is the guiding force behind this work. Rather than accepting Masterson's role as a sports reporter as merely a footnote in American history, this project begins with the premise that by examining Masterson's writings within the context of the greater events of his era, one can gain a unique insight into American society at this time. Masterson was a product of the American West and the mythology of the frontier, yet later in his life he became symbolic of another great event in American history the rural-to-urban movement. Were these events and these themes reflected in the writings of this one-time gunfighter, and if so how? The nature of this research requires a preliminary discussion of the methodology that will be employed. The primary sources which will be used are Masterson's published columns and articles. In this regard, the research will contain elements of content analysis, as it will follow a systematic approach to examining and attempting to quantify certain themes and elements in his writing. However, as Arthur Schlesinger, Jr., has observed, "almost all the important questions [in history) are important precisely because they are not susceptible to quantitative answers."1 Thus, the content analysis of Masterson's writing is meant only to "suggest or hint what motives or relationships might be."2 This is a methodology which has been practiced in communication research, where quantitative methods often are well suited to study topics such as a journalist's attitudes, as is being done here. A more detailed explanation of the methodology used is given in Chapter 5. However, it should be mentioned here that the "road map" followed in this research project was that provided by James D. Startt and Wm. David Sloan, who propose five "controls" in attempting to do interpretation in history. Briefly summarized, these are: There must be some logical criteria for the selection of the evidence used; The evidence must be studied in historical context (or, "a sense of historical time"); The study must include the opinions of others on the topic; Not only must "general statements rest on evidence..." but "[specific material must be related to generalization "; An effort must be made to transcend the present time and circumstances in order to examine Masterson by the standards of his day.3 Even in the newsroom, just as on the frontier, Masterson was a man who inspired not only fear and curiosity but above all respect. No doubt, his reputation as an old West gunman had much to do with the respect his newspaper column commanded. Still, as was noted in the rival New York Tribune, Masterson wrote with a "directness of expression" that resulted in stories and columns that contained within them valuable insights into America and American culture as Masterson saw them in this unique period of our history. From an historian's standpoint, the writings by Masterson may tell us more about America than the many writings and tall tales about him

Relationship of Wyoming Big Sagebrush Cover to Herbaceous Vegetation

We measured 328 sites in northern, central, and southern Montana and northern Wyoming during 2003 to test the relationship of herbaceous cover to Wyoming big sagebrush (Artemisia tridentata wyomingensis) cover. Long term annual precipitation at all sites was approximately 31 cm. Sagebrush and total herbaceous cover varied from 5 to 45 percent and 3.5 to 55 percent, respectively. Simple linear regression was the best fit model for predicting herbaceous cover from sagebrush cover using the highest Ra2 values as the model selection criteria. In northern Montana, herbaceous vegetation was predicted by sagebrush cover with the following model: Y = 37.4 – 0.61X (Ra2 = 0.16, P \u3c 0.001, n = 87). In central Montana, the model was Y = 14.0 – 0.00X (Ra2 = 0.00, P = 1.0, n = 155). In southern Montana, the model was Y = 35.9 – 0.39X (Ra2 = 0.14, P \u3c 0.001, n = 86). When all sites were combined, the best fit model was Y = 23.7 – 0.15X (Ra2 = 0.01, P \u3c 0.061, n = 328). This analysis determined that only 1 percent of the variation in herbaceous vegetation cover was associated with Wyoming big sagebrush cover. Management suggestions to reduce Wyoming big sagebrush in order to increase herbaceous production for greater sage-grouse (Centrocercus urophasianus) or livestock do not appear to be biologically sound. Keywords: Artemisia tridentata wyomingensis, line intercept, grass cover, Centrocercus urophasianus, forb cover, greater sage-grouse, sage-grouse habitat

HD 71636, A Newly Discovered Eclipsing Binary

Our differential BV photometric observations, acquired with an automated telescope at Fairborn Observatory, show that HD 71636 is an eclipsing binary. From follow-up red-wavelength spectroscopic observations we classify the primary and secondary as an F2 dwarf and an F5 dwarf, respectively. The system has a period of 5.01329 days and a circular orbit. We used the Wilson-Devinney program to simultaneously solve our BV light curves and radial velocities and determined a number of fundamental properties of the system. Comparison with evolutionary tracks indicates that both stars are well ensconced on the main sequence. The age of the system is about 1.2 billion years