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Full-Text Articles in Life Sciences

Characterizing The Evolutionary Path(S) To Early Homo, Lauren Schroeder, Charles C. Roseman, James M. Cheverud, Rebecca R. Ackermann Oct 2017

Characterizing The Evolutionary Path(S) To Early Homo, Lauren Schroeder, Charles C. Roseman, James M. Cheverud, Rebecca R. Ackermann

James Cheverud

Numerous studies suggest that the transition from Australopithecus to Homo was characterized by evolutionary innovation, resulting in the emergence and coexistence of a diversity of forms. However, the evolutionary processes necessary to drive such a transition have not been examined. Here, we apply statistical tests developed from quantitative evolutionary theory to assess whether morphological differences among late australopith and early Homo species in Africa have been shaped by natural selection. Where selection is demonstrated, we identify aspects of morphology that were most likely under selective pressure, and determine the nature (type, rate) of that selection. Results demonstrate that selection must …


Diaspora, A Large Family Of Ty3-Gypsy Retrotransposons In Glycine Max, Is An Envelope-Less Member Of An Endogenous Plant Retrovirus Lineage, Sho T. Yano, Bahman Panbehi, Arpita Das, Howard M. Laten Oct 2017

Diaspora, A Large Family Of Ty3-Gypsy Retrotransposons In Glycine Max, Is An Envelope-Less Member Of An Endogenous Plant Retrovirus Lineage, Sho T. Yano, Bahman Panbehi, Arpita Das, Howard M. Laten

Howard Laten

Background The chromosomes of higher plants are littered with retrotransposons that, in many cases, constitute as much as 80% of plant genomes. Long terminal repeat retrotransposons have been especially successful colonizers of the chromosomes of higher plants and examinations of their function, evolution, and dispersal are essential to understanding the evolution of eukaryotic genomes. In soybean, several families of retrotransposons have been identified, including at least two that, by virtue of the presence of an envelope-like gene, may constitute endogenous retroviruses. However, most elements are highly degenerate and are often sequestered in regions of the genome that sequencing projects initially …


Adaptive Evolution And Inherent Tolerance To Extreme Thermal Environments, Jennifer Cox, Alyxandria Schubert, Michael Travisano, Catherine Putonti Sep 2017

Adaptive Evolution And Inherent Tolerance To Extreme Thermal Environments, Jennifer Cox, Alyxandria Schubert, Michael Travisano, Catherine Putonti

Catherine Putonti

Background When introduced to novel environments, the ability for a species to survive and rapidly proliferate corresponds with its adaptive potential. Of the many factors that can yield an environment inhospitable to foreign species, phenotypic response to variation in the thermal climate has been observed within a wide variety of species. Experimental evolution studies using bacteriophage model systems have been able to elucidate mutations, which may correspond with the ability of phage to survive modest increases/decreases in the temperature of their environment. Results Phage ΦX174 was subjected to both elevated (50°C) and extreme (70°C+) temperatures for anywhere from a few …


A Review Of The Institute Of Medicine’S Analysis Of Using Chimpanzees In Biomedical Research, Robert C. Jones, Ray Greek Jul 2017

A Review Of The Institute Of Medicine’S Analysis Of Using Chimpanzees In Biomedical Research, Robert C. Jones, Ray Greek

Robert C. Jones, PhD

We argue that the recommendations made by the Institute of Medicine’s 2011 report, Chimpanzees in Biomedical and Behavioral Research: Assessing the Necessity, are methodologically and ethically confused. We argue that a proper understanding of evolution and complexity theory in terms of the science and ethics of using chimpanzees in biomedical research would have had led the committee to recommend not merely limiting but eliminating the use of chimpanzees in biomedical research. Specifically, we argue that a proper understanding of the difference between the gross level of examination of species and examinations on finer levels can shed light on important methodological …


Using Phylogenetically-Informed Annotation (Pia) To Search For Light-Interacting Genes In Transcriptomes From Non-Model Organisms, Daniel I. Speiser, M. Sabrina Pankey, Alexander K. Zaharoff, Barbara A. Battelle, Heather D. Bracken-Grissom, Jesse W. Breinholt, Seth M. Bybee, Thomas W. Cronin, Anders Garm, Annie R. Lindgren, Nipam H. Patel, Megan L. Porter, Meredith E. Protas, Anja S. Rivera, Jeanne M. Serb, Kirk S. Zigler, Keith A. Crandall, Todd H. Oakley Jan 2017

Using Phylogenetically-Informed Annotation (Pia) To Search For Light-Interacting Genes In Transcriptomes From Non-Model Organisms, Daniel I. Speiser, M. Sabrina Pankey, Alexander K. Zaharoff, Barbara A. Battelle, Heather D. Bracken-Grissom, Jesse W. Breinholt, Seth M. Bybee, Thomas W. Cronin, Anders Garm, Annie R. Lindgren, Nipam H. Patel, Megan L. Porter, Meredith E. Protas, Anja S. Rivera, Jeanne M. Serb, Kirk S. Zigler, Keith A. Crandall, Todd H. Oakley

Meredith Protas

Background: Tools for high throughput sequencing and de novo assembly make the analysis of transcriptomes (i.e. the suite of genes expressed in a tissue) feasible for almost any organism. Yet a challenge for biologists is that it can be difficult to assign identities to gene sequences, especially from non-model organisms. Phylogenetic analyses are one useful method for assigning identities to these sequences, but such methods tend to be time-consuming because of the need to re-calculate trees for every gene of interest and each time a new data set is analyzed. In response, we employed existing tools for phylogenetic analysis to …


Opsin Repertoire And Expression Patterns In Horseshoe Crabs: Evidence From The Genome Of Limulus Polyphemus (Arthropoda: Chelicerata), Barbara-Anne Battelle, Joseph F. Ryan, Karen E. Kempler, Spencer R. Saraf, Catherine E. Marten, Wesley C. Warren, Patrick J. Minx, Michael J. Montague, Pamela J. Green, Skye A. Schmidt, Lucinda Fulton, Nipam H. Patel, Meredith E. Protas, Richard K. Wilson, Megan L. Porter Jan 2017

Opsin Repertoire And Expression Patterns In Horseshoe Crabs: Evidence From The Genome Of Limulus Polyphemus (Arthropoda: Chelicerata), Barbara-Anne Battelle, Joseph F. Ryan, Karen E. Kempler, Spencer R. Saraf, Catherine E. Marten, Wesley C. Warren, Patrick J. Minx, Michael J. Montague, Pamela J. Green, Skye A. Schmidt, Lucinda Fulton, Nipam H. Patel, Meredith E. Protas, Richard K. Wilson, Megan L. Porter

Meredith Protas

Horseshoe crabs are xiphosuran chelicerates, the sister groupto arachnids. As such, they are important for understandingthemost recent common ancestor of Euchelicerata and the evolution and diversification of Arthropoda. Limulus polyphemus is the most investigated of the four extant species of horseshoe crabs, and the structure and function of its visual system have long been a major focus of studies critical for understanding the evolution of visual systems in arthropods. Likewise, studies of genes encoding Limulus opsins, the protein component of the visual pigments, are critical for understanding opsin evolution and diversification among chelicerates, where knowledge of opsins is limited, and …