Call synchrony and the evolutionary origins of leader preference in Neoconocephalus ensiger katydids

2016 ◽  
Author(s):  
◽  
Megan Murphy

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Many species of acoustically communicating insects and anurans display a female preference for males producing their calls just ahead of those of their neighbors. The evolutionary origin of these preferences is unclear. We test whether leader preference is adaptive in Neoconocephalus katydids. The ability to produce leading calls was not correlated with male quality in a species with leader preference or two closely related species without the preference. However, in N. ensiger, the species with the preference, females mating with leaders produced higher quality offspring than those mating with followers. This suggested that leader preference is adaptive and selected for in this species. The ability to produce leading calls was not heritable, meaning that the preference cannot have an evolutionary effect on the male trait and they will not become coupled. Male N. ensiger adjust the timing of their chirps relative to their neighbors, which leads to synchrony within a chorus. The mechanism used by N. ensiger males differs from that of all previously described species with acoustic synchrony. Neoconocephalus ensiger males adjust their actual intrinsic chirp rate to match that of other males. The characteristics that determine a male's ability to produce leading calls and the specific source of the female fitness benefit are yet unknown.

Author(s):  
Gerald B. Feldewerth

In recent years an increasing emphasis has been placed on the study of high temperature intermetallic compounds for possible aerospace applications. One group of interest is the B2 aiuminides. This group of intermetaliics has a very high melting temperature, good high temperature, and excellent specific strength. These qualities make it a candidate for applications such as turbine engines. The B2 aiuminides exist over a wide range of compositions and also have a large solubility for third element substitutional additions, which may allow alloying additions to overcome their major drawback, their brittle nature.One B2 aluminide currently being studied is cobalt aluminide. Optical microscopy of CoAl alloys produced at the University of Missouri-Rolla showed a dramatic decrease in the grain size which affects the yield strength and flow stress of long range ordered alloys, and a change in the grain shape with the addition of 0.5 % boron.


1980 ◽  
Vol 19 (03) ◽  
pp. 125-132
Author(s):  
G. S. Lodwick ◽  
C. R. Wickizer ◽  
E. Dickhaus

The Missouri Automated Radiology System recently passed its tenth year of clinical operation at the University of Missouri. This article presents the views of a radiologist who has been instrumental in the conceptual development and administrative support of MARS for most of this period, an economist who evaluated MARS from 1972 to 1974 as part of her doctoral dissertation, and a computer scientist who has worked for two years in the development of a Standard MUMPS version of MARS. The first section provides a historical perspective. The second deals with economic considerations of the present MARS system, and suggests those improvements which offer the greatest economic benefits. The final section discusses the new approaches employed in the latest version of MARS, as well as areas for further application in the overall radiology and hospital environment. A complete bibliography on MARS is provided for further reading.


2006 ◽  
Vol 23 (3-4) ◽  
pp. ii-ii

The International Colour Vision Society awarded the 2005 Verriest Medal to John D. Mollon, Professor of Visual Neuroscience at the University of Cambridge, UK. This award is bestowed by the Society to honor long-term contributions to the field of color vision. If the field of color vision were itself a rainbow, then Professor Mollon's contributions cover nearly its full spectrum, including the isolation and elucidation of basic chromatic coding mechanisms and the constraints that they impose on human (and more generally primate) visual performance, the genetic basis of spectral coding mechanisms, the ecological influences on and evolutionary origins of chromatic discrimination. He has been instrumental in the design of several new color vision tests and has extensively exploited abnormal models, both congenital and acquired, to further our understanding of normal mechanisms. He is especially appreciated for his keen and profound sense of the history of science, in particular with respect to the field of color vision. He has been a member of the society for over 25 years and is currently serving on its board of directors. He organized the 2001 ICVS meeting in Cambridge, celebrating the bicentennial of Thomas Young's lecture on color vision.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kensuke Okada ◽  
Masako Katsuki ◽  
Manmohan D. Sharma ◽  
Katsuya Kiyose ◽  
Tomokazu Seko ◽  
...  

AbstractTheory shows how sexual selection can exaggerate male traits beyond naturally selected optima and also how natural selection can ultimately halt trait elaboration. Empirical evidence supports this theory, but to our knowledge, there have been no experimental evolution studies directly testing this logic, and little examination of possible associated effects on female fitness. Here we use experimental evolution of replicate populations of broad-horned flour beetles to test for effects of sex-specific predation on an exaggerated sexually selected male trait (the mandibles), while also testing for effects on female lifetime reproductive success. We find that populations subjected to male-specific predation evolve smaller sexually selected mandibles and this indirectly increases female fitness, seemingly through intersexual genetic correlations we document. Predation solely on females has no effects. Our findings support fundamental theory, but also reveal unforseen outcomes—the indirect effect on females—when natural selection targets sex-limited sexually selected characters.


Author(s):  
Cari R. Bryant ◽  
Matt Bohm ◽  
Robert B. Stone ◽  
Daniel A. McAdams

This paper builds on previous concept generation techniques explored at the University of Missouri - Rolla and presents an interactive concept generation tool aimed specifically at the early concept generation phase of the design process. Research into automated concept generation design theories led to the creation of two distinct design tools: an automated morphological search that presents a designer with a static matrix of solutions that solve the desired input functionality and a computational concept generation algorithm that presents a designer with a static list of compatible component chains that solve the desired input functionality. The merger of both the automated morphological matrix and concept generation algorithm yields an interactive concept generator that allows the user to select specific solution components while receiving instantaneous feedback on component compatibility. The research presented evaluates the conceptual results from the hybrid morphological matrix approach and compares interactively constructed solutions to those returned by the non-interactive automated morphological matrix generator using a dog food sample packet counter as a case study.


2020 ◽  
Author(s):  
◽  
Mary Beth Brown

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI-COLUMBIA AT REQUEST OF AUTHOR.] This dissertation examines post-World War II student civil rights activism at two Midwestern college campuses, the University of Missouri (MU) and the University of Kansas (KU). Missouri and Kansas have conflicting histories concerning race dating back to Bleeding Kansas and the history of race relations on the campuses of KU and MU. This history is especially complicated during the period between 1946 and 1954 because of heightened student activism that challenged racial injustices. Race relations on campus largely mirrored that of the state's political environment, with KU having integrated in the 19th century, whereas MU did not desegregate until 1950. However, the same did not apply to the success of student activists at each school where MU students found success fighting against discriminatory practices in Columbia, whereas local business leaders and the university administration stymied KU students. The dissertation examines the exchange of ideas and strategy among students, which occurred through athletics, debates, guest speakers, and various regional and national groups. In particular, the study argues that campus spaces, such as residential co-ops and student organizations, were deeply significant because they served as incubators of activism by offering students a place to talk about racial and social injustice and plan ways to challenge these inequalities and effect change on campus and in the broader community.


2019 ◽  
Author(s):  
◽  
Teresa Milbrodt

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] This novel is the story of Tianne, a twenty-eight-year-old stained glass artist. She works two part-time jobs as a clerk at a stained glass supply store, and as an adjunct instructor at a community college. Her boyfriend Jeremiah is an academic adviser at the same college, but wants a career performing in comedy clubs. He uses a wheelchair due to spina bifida, and is cheerfully blunt that he could die from an undetected kidney infection. Tianne wrangles her own invisible disability, since endometriosis causes her to have awful cramps during her period that can keep her home from work. Tianne loves her jobs but worries about bills after her car breaks down. She envies Jeremiah's financial stability until he's fired for speaking his mind too many times to administration. Tianne fears for his health insurance coverage, while Jeremiah debates careers as a high school guidance counselor or touring comedy clubs. Throughout the book Tianne tries to chart a path though the instabilities of her body, Jeremiah's body, their career paths, and their romantic relationship, knowing that nothing is permanent. Hers is a story not of looking for stability, but coming to terms with instability, and finding spaces of adaptation to constant change.


2020 ◽  
Author(s):  
◽  
Kyle Logan Maddox

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] This dissertation outlines several results about prime characteristic singularities for which the nilpotent part under the induced Frobenius action on local cohomology is either finite colength or the entire module, collectively referred to here as nilpotent singularities. First, we establish a sufficient condition for the finiteness of the Frobenius test exponent for a local ring and apply it to conclude that nilpotent singularities have finite Frobenius test exponent. In joint work with Jennifer Kenkel, Thomas Polstra, and Austyn Simpson, we show that under mild conditions nilpotent singularities descend and ascend along faithfully flat maps. Consequently, we then prove that the loci of primes which are weakly F-nilpotent and F-nilpotent are open in the Zariski topology for rings which are either F-finite or essentially of fiiite type over an excellent local ring.


2015 ◽  
Author(s):  
◽  
Reza Houston

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This study is an examination of the relationship between political connections and the undertaking of major firm events. In our first essay, presented in Chapter 3, we examine the impact politically connected appointments have on firm acquisition behavior. Using proxy statements, we create a unique database of politically connected bidders and merger targets. We find that bidders who hire connected individuals to the board or management team are more likely to avoid merger litigation. Connected bidders make more bids after the appointment. These firms also bid on larger targets. We determine there is a positive relation between the control premium and the relative of the target's connections. Connected acquirers have superior post-merger accounting performance, particularly when they acquire a connected target firm. In the second essay, presented in Chapter 4, we examine the relationship between political connections of private firms and the initial public offering process. Using registration statement information, we create a unique database of politically connected IPO firms. We find that political connections are substitutes to high-quality underwriters and big four auditors. Politically connected firms manage earnings more highly upward than non-connected firms prior to the public offering. Politically connected firms also exhibit less underpricing than non-connected firms. Politically connected IPO firms also have superior post-IPO returns relative to non-connected IPO firms.


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