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2019

Evolution

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Full-Text Articles in Life Sciences

Review Of Megacormus Karsch, 1881, With Description Of A New Species (Scorpiones: Euscorpiidae), František Kovařík Dec 2019

Review Of Megacormus Karsch, 1881, With Description Of A New Species (Scorpiones: Euscorpiidae), František Kovařík

Euscorpius

Megacormus franckei sp. n. from Mexico is described and compared with all other species of the genus. Additional information is provided on the morphology, taxonomy and localities of genus Megacormus, mainly through color photographs of live and preserved specimens of all Megacormus species, as well as their habitats. Included is a key for all six known species of the genus Megacormus


Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly Dec 2019

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …


An Evolving Epigenome That Determines Tissue And Cell Specificity, Renee Louise Sears Dec 2019

An Evolving Epigenome That Determines Tissue And Cell Specificity, Renee Louise Sears

Arts & Sciences Electronic Theses and Dissertations

Understanding the mechanisms driving phenotypic variation is a major goal of biology that unifies classical genetics with the emerging fields of genomics and epigenomics. Human and mouse share over 90% of genes and global tissue-specific patterns of expression are maintained between the species. Thus, it is hypothesized that gene expression is influenced through distinctive regulation among species in order to account for the unmistakable phenotypic divergence. DNA methylation, histone modifications, open chromatin patterns, transcription factor binding, and other epigenetic factors are all associated with shaping, maintaining, and repressing regulatory regions which in turn coordinate gene expression. It is vital to …


Revision Of The Genus Reddyanus From Southeast Asia, With Description Of Five New Species From Cambodia, Malaysia, Thailand And Vietnam (Scorpiones: Buthidae), František Kovařík, František Šťáhlavský Dec 2019

Revision Of The Genus Reddyanus From Southeast Asia, With Description Of Five New Species From Cambodia, Malaysia, Thailand And Vietnam (Scorpiones: Buthidae), František Kovařík, František Šťáhlavský

Euscorpius

Five new species are described: Reddyanus furai sp. n. from Vietnam, R. hofereki sp. n. and R. majkusi sp. n. from Malaysia, R. rolciki sp. n. from Vietnam and Cambodia, and R. schwotti sp. n. from Thailand and Cambodia, fully complemented with color photographs of live and preserved specimens, as well as their habitats. New species are compared with all other species from this region. In addition to the analysis of external morphology, we also describe the karyotypes of R. furai sp. n. (2n=14), R. majkusi sp. n. (2n=16), R. rolciki sp. n. (2n=14), and R. schwotti (2n=11). …


Individual Based Model To Simulate The Evolution Of Insecticide Resistance, William B. Jamieson Dec 2019

Individual Based Model To Simulate The Evolution Of Insecticide Resistance, William B. Jamieson

Department of Mathematics: Dissertations, Theses, and Student Research

Insecticides play a critical role in agricultural productivity. However, insecticides impose selective pressures on insect populations, so the Darwinian principles of natural selection predict that resistance to the insecticide is likely to form in the insect populations. Insecticide resistance, in turn, severely reduces the utility of the insecticides being used. Thus there is a strong economic incentive to reduce the rate of resistance evolution. Moreover, resistance evolution represents an example of evolution under novel selective pressures, so its study contributes to the fundamental understanding of evolutionary theory.

Insecticide resistance often represents a complex interplay of multiple fitness trade-offs for individual …


Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xxii. Two New Species Of Neobuthus From Somaliland (Buthidae), František Kovařík Dec 2019

Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xxii. Two New Species Of Neobuthus From Somaliland (Buthidae), František Kovařík

Euscorpius

New information about taxonomy and distribution of the genus Neobuthus Hirst, 1911 is presented, based on material recently collected in Somaliland. N. awashensis Kovařík & Lowe, 2012 is reported from Somaliland for the first time. Two new species are described, N. haeckeli sp. n. and N. solegladi sp. n. An updated distribution map of the genus Neobuthus is provided.


Evolution - #0: Advanced Biological Systems, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #0: Advanced Biological Systems, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

The first unit of Advanced Biological Systems is focused on the theory of evolution, the mechanisms of evolutionary change, and discussions of the biological species concept. We discuss briefly how biodiversity stabilizes ecosystems. A study of biological evolution is placed first in the sequence of our curriculum to establish a foundation that explains the diversity of organisms, as well as biochemical processes, and the ongoing change process we witness today. These concepts will later be utilized in our curriculum to highlight cellular and metabolic diversity, the development of cancers, the interactions of bacteria with the ecosystem of the human host, …


Evolution - #8: Ecosystem Disrupted, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #8: Ecosystem Disrupted, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

This is the culminating activity for the evolution unit. For this assignment, students must research into the impact human industry has on a small part of our world. Students have had a brief introduction to the history of the planet and the role that carbon dioxide concentration play in climate change. The role of climate and weather patterns is important in a discussion of a chosen place on the planet. Students have spent a large amount of effort in understanding evolutionary theory and mechanisms and seen it in practice as they read about speciation. With this assignment, students can synthesize …


Evolution - #3: Evolution On The Web, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #3: Evolution On The Web, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

This lesson is a companion piece the previous one: Evolutionary Evidences and Inferences. It is completed supported by readings at an online site hosted by The University of California at Berkeley. The site is linked here:

http://evolution.berkeley.edu/evolibrary/article/0_0_0/evo_14


Evolution - #7: Speciation Jigsaw, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #7: Speciation Jigsaw, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

This is a lesson intended to be complementary to the selection simulation. Whereas the simulation was used to develop a conceptual understanding of selection, the readings done here are used to allow students to see the application of their conceptualized understanding to researched examples of selection and speciation.


Evolution - #2: Evolutionary Evidence And Inferences, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #2: Evolutionary Evidence And Inferences, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

The theory of evolution articulates elegantly a series of inferences from a vast collection of observations and evidence. We present some of those evidences here to stimulate in our students the sorts of scientific reasoning necessary to understand the presence and origin of diversity of life on the planet.


Evolution - #1: History Of Life, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #1: History Of Life, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

From the perspective of a biologist, the history of life on the Earth is a recurring story. Although details may be different, what happens today has precedence in the occurrences of the past. Two underlying ideas are vital for students to understand a modern conception of the theory of evolution. First, over long periods of time, and due to natural events, the environment of the Earth has changed, sometimes dramatically. Second, each environmental change has created more favorable conditions for some species to live and reproduce, while producing less favorable conditions for others. This first lesson in our unit on …


Evolution - #4: Genetic Drift And Founder Effect, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #4: Genetic Drift And Founder Effect, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

Genetic drift is a term used to describe chance fluctuations in the allelic frequencies in a population over time. The effects of genetic drift tend to be very minor in large populations, but they can be quite significant in small populations. Alleles are different functional forms in which a gene might exist. Humans have two alleles, sometimes the same but sometimes different, of most of their genes. In any population, it is possible to determine the frequency of all alleles. If these alleles get passed on to the next generation at random, then we should expect to see approximately the …


Evolution - #6: Selection Simulation, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #6: Selection Simulation, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

A modern understanding of the theory of evolution revolves around the selection of certain types within a population that over long time periods eventually leads to change of the species. This descent with modification is modeled with this activity, and leads to a subsequent lesson that has students reading about research into examples of speciation.


Evolution - #5: Globin Gene Evolution, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall Dec 2019

Evolution - #5: Globin Gene Evolution, Jessica Amacher, Sowmya Anjur, Donald Dosch, Sarah O'Leary-Driscoll, Crystal Randall

Unit 1: Evolution

For this lesson, students are guided through the steps necessary to compare nucleotide and amino acid sequences available at the National Center for Biotechnology Information that is maintained by the National Institutes of Health. The lesson starts with an examination of the alpha-globin gene. Alpha-globin is one of the proteins that constitutes hemoglobin. Student look at the various sequences of this gene that have been deposited at NCBI with a goal of determining alternative forms of the gene. The lesson then broadens the scope of comparison to include members of the globin protein family. Students create a phylogenetic tree that …


Identity Of The Central American Scorpion Centruroides Mahnerti Lourenço, 1983 (Scorpiones: Buthidae), Luis F. De Armas Nov 2019

Identity Of The Central American Scorpion Centruroides Mahnerti Lourenço, 1983 (Scorpiones: Buthidae), Luis F. De Armas

Euscorpius

The Central American scorpion Centruroides mahnerti Lourenço, 1983, was described on the basis of three female specimens (holotype and paratypes) from Momotombo Volcano, Nicaragua. Almost two decades later, it was synonymized under Centruroides koesteri Kraepelin, 1911 by Armas and Maes, without examination of the type specimen; but Teruel and Stockwell posteriorly argued that description and figures given for C. mahnerti are also similarly referable to juveniles of C. edwardsii (Gervais, 1843). Now, an evaluation of the holotype of C. mahnerti has definitively shown that it is a subadult female of C. koesteri. For the first time, photographs of the …


Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey Gadek Nov 2019

Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey Gadek

Biology ETDs

The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …


A New Species Of Kochius From Avra Valley, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey, Lawrence L. C. Jones, Brandon Myers Oct 2019

A New Species Of Kochius From Avra Valley, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey, Lawrence L. C. Jones, Brandon Myers

Euscorpius

A new scorpion species, Kochius colluvius sp. n. is described (Scorpiones: Vaejovidae). This small brown species is found in the Avra Valley near Tucson, Arizona, USA. It appears to be most similar to Kochius sonorae (Williams, 1971) and K. hirsuticauda (Banks, 1910). On all fingers examined, the fixed finger has 6 ID denticles and the movable finger has 7. There is no scalloping of the chela fingers. This species differs from all other vaejovids in Arizona by having a coarsely granulated exoskeleton.


Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel Oct 2019

Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel

Masters Theses

In order to ascertain the degree of compatibility in developmental restructuring and behavioral plasticity between two fish species frequently made subject of laboratory research (Metriaclima zebra & Danio rerio), alternative trophic niche exposure experiments utilizing novel three-prong feeding treatments were conducted to obtain morphometric data, which demonstrated both species do bear some degree of plasticity. The results are somewhat complicated by differences in locality of detectable restructuring, which may be due to disparity in the form-function relationship for each species’ lineage. Each is notable in the manner of respective species’ jaw protrusion, as it is driven by anterior …


Description Of The Adult Male Of Euscorpius Feti Tropea, 2013 (Scorpiones: Euscorpiidae), With Notes On Cave Ecology Of This Species, Gioele Tropea, Roman Ozimec Oct 2019

Description Of The Adult Male Of Euscorpius Feti Tropea, 2013 (Scorpiones: Euscorpiidae), With Notes On Cave Ecology Of This Species, Gioele Tropea, Roman Ozimec

Euscorpius

The adult male of Euscorpius feti Tropea, 2013 (Euscorpiidae) is described for the first time. A large series (45 specimens including the type material) has been studied, most of the material previously unpublished. E. feti has been found in as many as 17 caves in Croatia and Bosnia-Herzegovina, including the Adriatic islands, which makes it the most common Euscorpius species so far found in caves. Ecological notes on this species are presented.


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxi. Parabuthus (Buthidae) (Part Ii), With Description Of Five New Species From Somaliland And Ethiopia, František Kovařík, Graeme Lowe, Hassan S. A. Elmi, František Šťáhlavský Oct 2019

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxi. Parabuthus (Buthidae) (Part Ii), With Description Of Five New Species From Somaliland And Ethiopia, František Kovařík, Graeme Lowe, Hassan S. A. Elmi, František Šťáhlavský

Euscorpius

The complex of Parabuthus heterurus Pocock, 1897 is split into four species: P. heterurus Pocock, 1897 s. str. whose type locality and real distribution are discussed and corrected, and three herein described species, P. kabateki sp. n., P. robustus sp. n. and P. somalilandus sp. n. In the species complex of Parabuthus liosoma (Ehrenberg, 1828), P. erigavoensis sp. n. from Somaliland is described. Also described are P. mazuchi sp. n., sympatric with P. cimrmani Kovařík, 2004 and P. eritreaensis Kovařík, 2003 from Somaliland. New data are presented on the distribution of the genus Parabuthus Pocock, 1890 in the …


Description Of The Adult Female Of Diplocentrus Lachua (Scorpiones: Scorpionidae: Diplocentrinae) From Northeastern Alta Verapaz, Guatemala, Rony E. Trujillo, Luis F. De Armas, Carlos A. Gaitán Oct 2019

Description Of The Adult Female Of Diplocentrus Lachua (Scorpiones: Scorpionidae: Diplocentrinae) From Northeastern Alta Verapaz, Guatemala, Rony E. Trujillo, Luis F. De Armas, Carlos A. Gaitán

Euscorpius

The female of the scorpion Diplocentrus lachua Armas, Trujillo & Agreda, 2011 is herein described, on the basis of a single specimen collected at Parque Nacional Laguna Lachuá, Alta Verapaz Department, Guatemala, type locality for this species. An emended diagnosis is provided and the known distribution of all described Guatemalan Diplocentrus species is graphically presented.


Evidence For Adaptive Introgression Of Exons Across A Hybrid Swarm In Deer, Emily Latch, Margaret Haines, Gordon Luikart, Stephen Amish, Seth Smith Oct 2019

Evidence For Adaptive Introgression Of Exons Across A Hybrid Swarm In Deer, Emily Latch, Margaret Haines, Gordon Luikart, Stephen Amish, Seth Smith

Biological Sciences Faculty Articles

Background: Secondary contact between closely related lineages can result in a variety of outcomes, including hybridization, depending upon the strength of reproductive barriers. By examining the extent to which different parts of the genome introgress, it is possible to infer the strength of selection and gain insight into the evolutionary trajectory of lineages. Following secondary contact approximately 8000 years ago in the Pacific Northwest, mule deer (Odocoileus hemionus hemionus) and black-tailed deer (O. h. columbianus) formed a hybrid swarm along the Cascade mountain range despite substantial differences in body size (up to two times) and habitat preference. In this study, …


Fish Sentience Denial: Muddying The Waters, Lynne U. Sneddon, Javier Lopez-Luna, David C.C. Wolfenden, Matthew C. Leach, Ana M. Valentim, Peter J. Steenbergen, Nabila Bardine, Amanda D. Currie, Donald M. Broom, Culum Brown Sep 2019

Fish Sentience Denial: Muddying The Waters, Lynne U. Sneddon, Javier Lopez-Luna, David C.C. Wolfenden, Matthew C. Leach, Ana M. Valentim, Peter J. Steenbergen, Nabila Bardine, Amanda D. Currie, Donald M. Broom, Culum Brown

Lynne Sneddon, PhD

Recent empirical studies have reported evidence that many aquatic species, including fish, cephalopods and crustaceans, have the capacity for nociception and pain, and that their welfare should be taken into consideration. Some sceptics, rejecting the precautionary principle, have denied that any study demonstrates pain or other aspects of sentience in fish. This target article discusses some of the scientific shortcomings of these critiques through a detailed analysis of a study exploring nociception and analgesia in larval zebrafish.


Ample Evidence For Fish Sentience And Pain, Lynne U. Sneddon, David C.C. Wolfenden, Matthew C. Leach, Ana M. Valentim, Peter J. Steenbergen, Nabila Bardine, Donald M. Broom, Culum Brown Sep 2019

Ample Evidence For Fish Sentience And Pain, Lynne U. Sneddon, David C.C. Wolfenden, Matthew C. Leach, Ana M. Valentim, Peter J. Steenbergen, Nabila Bardine, Donald M. Broom, Culum Brown

Lynne Sneddon, PhD

The majority of commentaries are supportive of our position on the scepticism that muddies the waters surrounding fish pain and sentience. There is substantial empirical evidence for pain in fish. Animals’ experience of pain cannot be compared to artificial intelligence (AI) because AI can only mimic responses to nociceptive input on the basis of human observations and programming. Accepting that fish are sentient would not be detrimental to the industries reliant on fish. A more proactive discussion between scientists and stakeholders is needed to improve fish welfare for the benefit of all.


Anthropomorphic Denial Of Fish Pain, Lynne U. Sneddon, Matthew C. Leach Sep 2019

Anthropomorphic Denial Of Fish Pain, Lynne U. Sneddon, Matthew C. Leach

Lynne Sneddon, PhD

Key (2016) affirms that we do not know how the fish brain processes pain but denies — because fish lack a human-like cortex — that fish can feel pain. He affirms that birds, like fish, have a singly-laminated cortex and that the structure of the bird brain is quite different from that of the human brain, yet he does not deny that birds can feel pain. In this commentary we describe how Key cites studies that substantiate mammalian pain but discounts the same kind of data as evidence of fish pain. We suggest that Key's interpretations are illogical, do not …


Taxonomic Reassessment Of The Genera Lychas, Mesobuthus, And Olivierus, With Descriptions Of Four New Genera (Scorpiones: Buthidae), František Kovařík Sep 2019

Taxonomic Reassessment Of The Genera Lychas, Mesobuthus, And Olivierus, With Descriptions Of Four New Genera (Scorpiones: Buthidae), František Kovařík

Euscorpius

The diagnostic characters are reassessed and defined for the genera Lychas C. L. Koch, 1845, Mesobuthus Vachon, 1950, and Olivierus Farzanpay, 1987 (the latter is restored from synonymy with Mesobuthus). Four new genera are described: Aegaeobuthus gen. n. (type species Buthus gibbosus Brullé, 1832), Afrolychas gen. n. (type species Isometrus burdoi Simon, 1882), Janalychas gen. n. (type species Lychas srilankensis Lourenço, 1997), and Spelaeolychas gen. n. (type species Isometrus hosei Pocock, 1891). Type species are designated for subgenera Lychas (Distotrichus) Tikader & Bastawade, 1983 (type species Isometrus nigristernis Pocock, 1899), Lychas (Alterotrichus) Tikader & Bastawade, 1983 (type species Scorpio …


Seven New Alpine Species Of The Genus Alpiscorpius Gantenbein Et Al., 1999, Stat. N. (Scorpiones: Euscorpiidae), František Kovařík, Jana Štundlová, Victor Fet, František Šťáhlavský Sep 2019

Seven New Alpine Species Of The Genus Alpiscorpius Gantenbein Et Al., 1999, Stat. N. (Scorpiones: Euscorpiidae), František Kovařík, Jana Štundlová, Victor Fet, František Šťáhlavský

Euscorpius

Two subgenera of Euscorpius Thorell, 1876 (Scorpiones: Euscorpiidae) are elevated to the genus status: Alpiscorpius Gantenbein et al., 1999, stat. n. and Tetratrichobothrius Birula, 1917, stat. n. Seven new Alpine scorpion species are described and illustrated: Alpiscorpius delta sp. n. (Italy) from the “alpha group” (“germanus complex”); A. kappa sp. n. (Slovenia) and A. lambda sp. n. (Slovenia) from the “germanus group” (“germanus complex”); A. omega sp. n. (Slovenia), A. omikron sp. n. (Slovenia), A. sigma sp. n. (Italy, Slovenia), and A. ypsilon sp. n. (Austria, Slovenia) …


Raising Consciousness About Chicken Consciousness, Bernard Rollin Sep 2019

Raising Consciousness About Chicken Consciousness, Bernard Rollin

Bernard Rollin, PhD

The topics explored by Marino are definitive, and should work well to lay to rest forever the widespread belief that chickens have no personality, are unintelligent, or in any other way lack a mental life.


Far More To Sheep Than Meets The Casual Eye, Bernard Rollin Sep 2019

Far More To Sheep Than Meets The Casual Eye, Bernard Rollin

Bernard Rollin, PhD

Marino & Merskin’s survey of the cognitive and social capacities of sheep is an eye-opener about the individuality and emotionality of this most maligned of all farm animals. My own eyes had already been opened by an adopted orphaned lamb, so much more like a dog as a companion animal than the mindless robot I had been conditioned to expect. I am morally certain that Marino & Merskin’s survey will have a similar effect on readers open to changing their minds.