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Richmond, IN, United States

Earlham College is a liberal arts college in Richmond, Indiana. It was founded in 1847 by Quakers and has approximately 1,200 students.In keeping with Friends' belief in equality, everyone addresses each other at Earlham by his or her first name, without the use of titles such as "doctor" or "professor"; likewise, "freshmen" are referred to as "first year ".While Earlham is primarily a residential undergraduate college, it also has two graduate programs — the master of arts in teaching and the master of education — which provide a route for teacher licensure to students with liberal arts undergraduate degrees; there is also an affiliated graduate seminary, the Earlham School of Religion.Earlham College is listed in Loren Pope's book, Colleges That Change Lives, and has produced two Nobel laureates . Wikipedia.

Ceballos C.P.,University of Antioquia | Iverson J.B.,Earlham College
Biological Journal of the Linnean Society

Rensch's rule, a macroevolutionary pattern in which sexual size dimorphism (SSD) increases with body size in male-biased SSD species, or decreases with female-biased SSD species, has been investigated in many vertebrates because it indicates whether SSD is being driven by sexual selection or a different force (i.e. fecundity or natural selection). Evidence in turtles has shown some conflicting results, which may be explained by the different phylogenies used in the analyses. Because the newly available well-resolved phylogeny of family Kinosternidae provides evidence for the ancient monophyly of Staurotypidae and Kinosternidae and their recognition as separate families (previously Staurotypidae was considered as a subfamily within Kinosternidae) and introduced the genus Cryptochelys for the monophyletic leucostomum clade, we revisit the pattern of SSD and body size in Kinosternidae. By contrast to what had been proposed, we found that the Kinosternidae as formerly recognized (i.e. including Staurotypus and Claudius) and the restricted Kinosternidae both follow a pattern consistent with Rensch's rule. Our analysis with published body size data did not change our results, confirming the importance of the phylogeny used in macroevolutionary studies. © 2014 The Linnean Society of London. Source

Reproduction in the red-cheeked mud turtle (Kinosternon scorpioides cruentatum) was studied in southeastern Mexico and Belize (Yucatan Peninsula) on the basis of museum and field-collected specimens. Adult females (mean carapace length CL110 mm) were not significantly larger than adult males (mean CL108 mm). Females matured at 100-105 mm CL and an estimated age of 9-10 years. Annual reproduction by females was apparently continuous for at least 10 months of the year (August-June), with the production of multiple annual clutches (possibly as many as 5) being typical and the number of clutches per year increasing with female size. Eggs exhibit diapause and embryonic estivation and apparently hatch in nature during the wet season (June-August) after up to 9 months in the nest. Modal clutch size was only 2 eggs (mean 2.2; range 1-4), and clutch size increased with female body size. Egg size averaged 31.5 × 16.6 mm and 5.5 g and did not vary with female body size. Relative egg mass (REMmean egg mass×100/body mass-clutch mass) averaged 2.3, was lower in larger clutches, and decreased with increased body size. Relative clutch mass (RCMREM×clutch size) averaged 4.85, similar to that for the sympatric K. creaseri (4.5), the 2 lowest values reported for any studied Kinosternon population. RCM did not vary with female body size or clutch size. Females devote a relatively constant proportion of body mass to each clutch, and increases in reproductive output with size and age are apparently accomplished by increases in clutch size (but not egg size) and clutch frequency. This unusual suite of reproductive traits (small body size, small clutch size, production of up to 5 clutches per year, reduced relative clutch mass, and embryonic diapause and estivation) may have been instrumental in the success of this species at colonizing more of South America than any other Mesoamerican turtle genus or species and in less than 4 million years. © 2010 Chelonian Research Foundation. Source

Linksvayer T.A.,University of Pennsylvania | Busch J.W.,Washington State University | Smith C.R.,Earlham College

We suggest that supergenes, groups of co-inherited loci, may be involved in a range of intriguing genetic and evolutionary phenomena in insect societies, and may play broad roles in the evolution of cooperation and conflict. Supergenes are central in the evolution of an array of traits including self-incompatibility, mimicry, and sex chromosomes. Recently, researchers identified a large supergene, described as a social chromosome, which controls social organization in the fire ant. This system was previously considered to be a remarkable example of a single gene affecting a complex social trait. We describe how selection may commonly favor reduced recombination and the formation of supergenes for social traits, and once formed, supergenes may strongly influence further evolutionary dynamics within and between lineages. The evolution of supergenes, and even wholly non-recombining genomes, may be particularly common in systems in which genetically distinct lineages can form mutually reinforcing socially parasitic relationships. © 2013 WILEY Periodicals, Inc. Source

Iverson J.B.,Earlham College | Le M.,National American University | Ingram C.,American Museum of Natural History
Molecular Phylogenetics and Evolution

The turtle family Kinosternidae comprises 25 living species of mud and musk turtles confined to the New World. Previous attempts to reconstruct a phylogenetic history of the group have employed morphological, isozyme, and limited mitochondrial DNA sequence data, but have not been successful in producing a well-resolved phylogeny. With tissues from every recognized species and most subspecies, we sequenced three mitochondrial (cyt b, 12S, 16S) and three nuclear markers (C mos, RAG1, RAG2). Our analyses revealed the existence of three well-resolved clades within the Kinosterninae (aged >22. mya), only two of which have been named: Sternotherus and Kinosternon. We here describe the third clade as a new genus. The evolutionary relationships among most species were well resolved, although those belonging to the K. scorpioides species group will require more extensive geographic and genetic sampling. Divergence time estimates and ancestral area reconstructions permitted the development of the first rigorous hypothesis of the zoogeographic history of the group, including support for three separate dispersals into South America, at least two of which preceded the closure of the Panamanian portal. © 2013 Elsevier Inc. Source

Custelcean R.,Oak Ridge National Laboratory | Bonnesen P.V.,Oak Ridge National Laboratory | Duncan N.C.,Oak Ridge National Laboratory | Zhang X.,Oak Ridge National Laboratory | And 4 more authors.
Journal of the American Chemical Society

We present an extensive study of a novel class of de novo designed tetrahedral M 4L 6 (M = Ni, Zn) cage receptors, wherein internal decoration of the cage cavities with urea anion-binding groups, via functionalization of the organic components L, led to selective encapsulation of tetrahedral oxoanions EO 4 n- (E = S, Se, Cr, Mo, W, n = 2; E = P, n = 3) from aqueous solutions, based on shape, size, and charge recognition. External functionalization with tBu groups led to enhanced solubility of the cages in aqueous methanol solutions, thereby allowing for their thorough characterization by multinuclear ( 1H, 13C, 77Se) and diffusion NMR spectroscopies. Additional experimental characterization by electrospray ionization mass spectrometry, UV-vis spectroscopy, and single-crystal X-ray diffraction, as well as theoretical calculations, led to a detailed understanding of the cage structures, self-assembly, and anion encapsulation. We found that the cage self-assembly is templated by EO 4 n- oxoanions (n ≥ 2), and upon removal of the templating anion the tetrahedral M 4L 6 cages rearrange into different coordination assemblies. The exchange selectivity among EO 4 n- oxoanions has been investigated with 77Se NMR spectroscopy using 77SeO 4 2- as an anionic probe, which found the following selectivity trend: PO 4 3- ≫ CrO 4 2- > SO 4 2- > SeO 4 2- > MoO 4 2- > WO 4 2-. In addition to the complementarity and flexibility of the cage receptor, a combination of factors have been found to contribute to the observed anion selectivity, including the anions' charge, size, hydration, basicity, and hydrogen-bond acceptor abilities. © 2012 American Chemical Society. Source

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