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2019

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The Daily Gamecock, Monday, December 2, 2019, University Of South Carolina, Office Of Student Media Dec 2019

The Daily Gamecock, Monday, December 2, 2019, University Of South Carolina, Office Of Student Media

December

No abstract provided.


The Effects Of Urbanization On Bee Communities Depends On Floral Resource Availability And Bee Functional Traits., Caleb J Wilson, Mary A Jamieson Dec 2019

The Effects Of Urbanization On Bee Communities Depends On Floral Resource Availability And Bee Functional Traits., Caleb J Wilson, Mary A Jamieson

Entomology Faculty Publications

Wild bees are important pollinators in many ecosystems threatened by anthropogenic disturbance. Urban development can reduce and degrade natural habitat for bees and other pollinators. However, some researchers suggest that cities could also provide refuge for bees, given that agricultural intensification may pose a greater risk. In this study, we surveyed bee communities at 15 farms and gardens across an urban-rural gradient in southeastern Michigan, USA to evaluate the effect of urbanization on bees. We examined how floral resources, bee functional traits, temperature, farm size, and the spatial scale of analysis influence bee response to urbanization. We found that urbanization …


Characterization And Membrane Stability Study For The Switchable Polarity Solvent N,N-Dimethylcyclohexylamine As A Draw Solute In Forward Osmosis, Kevin K. Reimund Dec 2019

Characterization And Membrane Stability Study For The Switchable Polarity Solvent N,N-Dimethylcyclohexylamine As A Draw Solute In Forward Osmosis, Kevin K. Reimund

Master's Theses

No abstract provided.


Intramuscular Injection Of Plant Derived Antimicrobials: A Potenial Use Against M.Bovis In Cattle, Elizabeth Johnson Dec 2019

Intramuscular Injection Of Plant Derived Antimicrobials: A Potenial Use Against M.Bovis In Cattle, Elizabeth Johnson

Master's Theses

Plant derived antimicrobials (PDAs) such as trans-cinnamaldehyde, eugenol and carvacrol, possess strong antibacterial properties yet are generally regarded as safe. In the current crisis of antibiotic resistance, the use of PDAs as alternatives to prevent and control bacterial infections in livestock has gained momentum. The inhibitory effects of PDAs on common bacteria such as C.difficile, Listeria, Salmonella have been widely studied. PDAs have also been found effective in wall-less bacteria such as Mycoplasma, for which common antibiotics are not effective and vaccines are not always effective. In animal husbandry, PDAs can be potentially added in feed to metaphalactively prevent …


Best Practices For Renovating Golf Course Fairways To More Sustainable Bentgrasses In The Northeastern United States, Zoe Esponda Dec 2019

Best Practices For Renovating Golf Course Fairways To More Sustainable Bentgrasses In The Northeastern United States, Zoe Esponda

Master's Theses

No abstract provided.


American Black Bears (Ursus Americanus) Of The Paunsaugunt Plateau: Movements And Habitat Use, Rebekah Adriana Castro Dungan Dec 2019

American Black Bears (Ursus Americanus) Of The Paunsaugunt Plateau: Movements And Habitat Use, Rebekah Adriana Castro Dungan

Theses and Dissertations

Concerns over human-bear conflict and questions about the ecology of Paunsaugunt Plateau's population of black bears (Ursus americanus) arose due to their visitation to popular recreation sites. Greater insight about bears and their habitat use provides a foundation for conflict mitigation and effective management decisions. Between 2014 and 2017, seventeen black bears (11 female, 6 male) were fitted with global positioning system (GPS) radio-collars so that we could track their locations, daily activity patterns, and ambient temperatures. By analyzing bear locations, we calculated annual and seasonal home ranges for 16 bears, including 25 den sites. Home ranges typically consisted of …


New Possibilities For Stilt Building, Zhuming Liu Dec 2019

New Possibilities For Stilt Building, Zhuming Liu

Theses

The purpose of the thesis lies in exploring the new possibilities of the stilt building in dealing with two sustainability problems caused by urban development: the Lack of Public Greening in Prosperous, High-density Areas, and the Continuous Sprawl of Private Housing in Suburbs.

As a functional building method with a long history, stilt building, or known as building with “The Pilotis,” regained its vitality in the 20th century with Le Corbusier. However, the common application mode of today’s stilt building has deviated from Corbusier's original intention, which was to provide sheltered outdoor green space for residents in the city. This …


Application Of Bradford's Law Of Scattering And Obsolescence In The Literature Of Chemistry: A Study Based On Doctoral Theses, Mithu Anjali Gayan, Sanjay Kumar Singh Dec 2019

Application Of Bradford's Law Of Scattering And Obsolescence In The Literature Of Chemistry: A Study Based On Doctoral Theses, Mithu Anjali Gayan, Sanjay Kumar Singh

Library Philosophy and Practice (e-journal)

The proposed study tries to investigate citation pattern of Chemistry theses submitted to Central library Tripura University. The study considered only those theses submitted to Shodhganga, the Indian ETD initiative. Hence data were collected from 20 theses constituting 6214 citations during 2007 to 2016. Bardford’s law is used to find out the core journals in the field of Chemistry. The rank list of journals showed “Phytochemistry” is the most cited journal. The dataset of the study did not follow the Bradford’s law. However, the dataset follow the Leimkuhler’s model. Half life of Chemistry journals is found to be 12.6 years. …


Fracture Repair Requires Trka Signaling By Skeletal Sensory Nerves., Zhu Li, Carolyn A Meyers, Leslie Chang, Seungyong Lee, Zhi Li, Ryan Tomlinson, Ahmet Hoke, Thomas L Clemens, Aaron W James Dec 2019

Fracture Repair Requires Trka Signaling By Skeletal Sensory Nerves., Zhu Li, Carolyn A Meyers, Leslie Chang, Seungyong Lee, Zhi Li, Ryan Tomlinson, Ahmet Hoke, Thomas L Clemens, Aaron W James

Department of Orthopaedic Surgery Faculty Papers

Bone is richly innervated by nerve growth factor-responsive (NGF-responsive) tropomyosin receptor kinase A-expressing (TrKa-expressing) sensory nerve fibers, which are required for osteochondral progenitor expansion during mammalian skeletal development. Aside from pain sensation, little is known regarding the role of sensory innervation in bone repair. Here, we characterized the reinnervation of tissue following experimental ulnar stress fracture and assessed the impact of loss of TrkA signaling in this process. Sequential histological data obtained in reporter mice subjected to fracture demonstrated a marked upregulation of NGF expression in periosteal stromal progenitors and fracture-associated macrophages. Sprouting and arborization of CGRP+TrkA+ sensory nerve fibers …


Spectroscopic And Computational Comparisons Of Thiolate-Ligated Ferric Nonheme Complexes To Cysteine Dioxygenase: Second-Sphere Effects On Substrate (Analogue) Positioning, Anne A. Fischer, Joshua R. Miller, Richard J. Jodts, Danushka M. Ekanayake, Sergey V. Lindeman, Thomas C. Brunold, Adam T. Fiedler Dec 2019

Spectroscopic And Computational Comparisons Of Thiolate-Ligated Ferric Nonheme Complexes To Cysteine Dioxygenase: Second-Sphere Effects On Substrate (Analogue) Positioning, Anne A. Fischer, Joshua R. Miller, Richard J. Jodts, Danushka M. Ekanayake, Sergey V. Lindeman, Thomas C. Brunold, Adam T. Fiedler

Chemistry Faculty Research and Publications

Parallel spectroscopic and computational studies of iron(III) cysteine dioxygenase (CDO) and synthetic models are presented. The synthetic complexes utilize the ligand tris(4,5-diphenyl-1-methylimidazol-2-yl)phosphine (Ph2TIP), which mimics the facial three-histidine triad of CDO and other thiol dioxygenases. In addition to the previously reported [FeII(CysOEt)(Ph2TIP)]BPh4 (1; CysOEt is the ethyl ester of anionic l-cysteine), the formation and crystallographic characterization of [FeII(2-MTS)(Ph2TIP)]BPh4 (2) is reported, where the methyl 2-thiosalicylate anion (2-MTS) resembles the substrate of 3-mercaptopropionate dioxygenase (MDO). One-electron chemical oxidation of 1 and 2 yields ferric species …


Components Of The Ribosome Biogenesis Pathway Underlie Establishment Of Telomere Length Set Point In Arabidopsis, Liliia R. Abdulkina, Callie Kobayashi, John T. Lovell, Inna B. Chastukkhina, Behailu B. Aklilu, Inna A, Agabekian, Ana V. Suescún, Lia R. Valeeva, Chuluuntsetseg Nyamsuren, Galina V. Aglyamova, Margarita R. Sharipova, Dorothy E. Shippen, Thomas E. Juenger, Eugene V. Shakirov Dec 2019

Components Of The Ribosome Biogenesis Pathway Underlie Establishment Of Telomere Length Set Point In Arabidopsis, Liliia R. Abdulkina, Callie Kobayashi, John T. Lovell, Inna B. Chastukkhina, Behailu B. Aklilu, Inna A, Agabekian, Ana V. Suescún, Lia R. Valeeva, Chuluuntsetseg Nyamsuren, Galina V. Aglyamova, Margarita R. Sharipova, Dorothy E. Shippen, Thomas E. Juenger, Eugene V. Shakirov

Biological Sciences Faculty Research

Telomeres cap the physical ends of eukaryotic chromosomes to ensure complete DNA replication and genome stability. Heritable natural variation in telomere length exists in yeast, mice, plants and humans at birth; however, major effect loci underlying such polymorphism remain elusive. Here, we employ quantitative trait locus (QTL) mapping and transgenic manipulations to identify genes controlling telomere length set point in a multi-parent Arabidopsis thaliana mapping population. We detect several QTL explaining 63.7% of the total telomere length variation in the Arabidopsis MAGIC population. Loss-of-function mutants of the NOP2A candidate gene located inside the largest effect QTL and of two other …


Scientometric Mapping And Visualization Of Environmental Science Research: A Case Study, Sanku Bilas Roy Dec 2019

Scientometric Mapping And Visualization Of Environmental Science Research: A Case Study, Sanku Bilas Roy

Library Philosophy and Practice (e-journal)

The present study attempts to emphasize quantitatively the development of environmental science literature in terms of publication output as per Scopus database for thirty years (1989-2018). The focus of this paper is to analysis the literature published by the researchers of the University of Calcutta during the period under study. Total 1093 records have been retrieved for this study. An exponential growth rate has been identified. Authorship trend was towards multi-authored papers. Most prolific authors and most productive journals have been traced. The most productive journal is Environmental Monitoring and Assessment. Co-authorship pattern and Co-occurrence of keywords have also been …


Topological Data Analysis For Clustering And Classifying Time Series, Renjie Chen Dec 2019

Topological Data Analysis For Clustering And Classifying Time Series, Renjie Chen

Doctoral Dissertations

Topological Data Analysis (TDA), which refers to methods of utilizing topological

features in data (such as connected components, tunnels, voids, etc.) has gained considerable

momentum. More recently, TDA has been increasingly used for analyzing time

series. The recent researches of using TDA in time series are mainly focused on unsupervised

and supervised learning. In this thesis, a review of TDA will be provided,

following by using TDA in time series for doing unsupervised and supervised learning

for different applications.


Investigation Of Antimicrobial Secondary Metabolites From Bacterial Isolates Associated With The Hawaiian Bobtail Squid (Euprymna Scolopes), Samantha Gromek Dec 2019

Investigation Of Antimicrobial Secondary Metabolites From Bacterial Isolates Associated With The Hawaiian Bobtail Squid (Euprymna Scolopes), Samantha Gromek

Doctoral Dissertations

A beneficial host-microbe symbiosis that has been extensively studied is the association of the Hawaiian bobtail squid, Euprymna scolopes, with the bioluminescent bacterium Vibrio fischeri in the squid light organ. Our research used the Hawaiian bobtail squid as a model system to begin investigating the functional role of secondary metabolites associated with the accessory nidamental gland (ANG), a reproductive organ present in sexually mature female cephalopods, and jelly coat (JC) bacteria. Using this model organism, prior research supports that bacteria from the ANG are deposited into the egg JC. Subsequently, the JC bacteria produce compounds as a chemical defense …


Allele-Specific Rna Interference Prevents Neuropathy In Charcot-Marie-Tooth Disease Type 2d Mouse Models., Kathryn H Morelli, Laurie B Griffin, Nettie K Pyne, Lindsay M Wallace, Allison M Fowler, Stephanie N Oprescu, Ryuichi Takase, Na Wei, Rebecca Meyer-Schuman, Dattatreya Mellacheruvu, Jacob O Kitzman, Samuel G Kocen, Timothy J Hines, Emily L Spaulding, James R Lupski, Alexey Nesvizhskii, Pedro Mancias, Ian J Butler, Xiang-Lei Yang, Ya-Ming Hou, Anthony Antonellis, Scott Q Harper, Robert W Burgess Dec 2019

Allele-Specific Rna Interference Prevents Neuropathy In Charcot-Marie-Tooth Disease Type 2d Mouse Models., Kathryn H Morelli, Laurie B Griffin, Nettie K Pyne, Lindsay M Wallace, Allison M Fowler, Stephanie N Oprescu, Ryuichi Takase, Na Wei, Rebecca Meyer-Schuman, Dattatreya Mellacheruvu, Jacob O Kitzman, Samuel G Kocen, Timothy J Hines, Emily L Spaulding, James R Lupski, Alexey Nesvizhskii, Pedro Mancias, Ian J Butler, Xiang-Lei Yang, Ya-Ming Hou, Anthony Antonellis, Scott Q Harper, Robert W Burgess

Department of Biochemistry and Molecular Biology Faculty Papers

Gene therapy approaches are being deployed to treat recessive genetic disorders by restoring the expression of mutated genes. However, the feasibility of these approaches for dominantly inherited diseases - where treatment may require reduction in the expression of a toxic mutant protein resulting from a gain-of-function allele - is unclear. Here we show the efficacy of allele-specific RNAi as a potential therapy for Charcot-Marie-Tooth disease type 2D (CMT2D), caused by dominant mutations in glycyl-tRNA synthetase (GARS). A de novo mutation in GARS was identified in a patient with a severe peripheral neuropathy, and a mouse model precisely recreating the mutation …


Sik3 Suppresses Neuronal Hyperexcitability By Regulating The Glial Capacity To Buffer K+ And Water, Hailun Li, Alexandra Russo, Aaron Diantonio Dec 2019

Sik3 Suppresses Neuronal Hyperexcitability By Regulating The Glial Capacity To Buffer K+ And Water, Hailun Li, Alexandra Russo, Aaron Diantonio

Open Access Publications

Glial regulation of extracellular potassium (K


Disease-Associated Mutations In Niemann-Pick Type C1 Alter Er Calcium Signaling And Neuronal Plasticity, Scott A. Tiscione, Oscar Vivas, Kenneth S. Ginsburg, Donald M. Bers, Daniel S. Ory, Luis F. Santana, Rose E. Dixon, Eamonn J. Dickson Dec 2019

Disease-Associated Mutations In Niemann-Pick Type C1 Alter Er Calcium Signaling And Neuronal Plasticity, Scott A. Tiscione, Oscar Vivas, Kenneth S. Ginsburg, Donald M. Bers, Daniel S. Ory, Luis F. Santana, Rose E. Dixon, Eamonn J. Dickson

Open Access Publications

Niemann-Pick type C1 (NPC1) protein is essential for the transport of externally derived cholesterol from lysosomes to other organelles. Deficiency of NPC1 underlies the progressive NPC1 neurodegenerative disorder. Currently, there are no curative therapies for this fatal disease. Given the Ca


Association Of Longitudinal Changes In Cerebrospinal Fluid Total Tau And Phosphorylated Tau 181 And Brain Atrophy With Disease Progression In Patients With Alzheimer Disease, Jorge J. Llibre-Guerra, Yan Li, Suzanne E. Schindler, Brian A. Gordon, Anne M. Fagan, John C. Morris, Tammie L.S. Benzinger, Jason Hassenstab, Sarah B. Berman, David M. Holtzman, Chengjie Xiong, Randall J. Bateman, Eric Mcdade Dec 2019

Association Of Longitudinal Changes In Cerebrospinal Fluid Total Tau And Phosphorylated Tau 181 And Brain Atrophy With Disease Progression In Patients With Alzheimer Disease, Jorge J. Llibre-Guerra, Yan Li, Suzanne E. Schindler, Brian A. Gordon, Anne M. Fagan, John C. Morris, Tammie L.S. Benzinger, Jason Hassenstab, Sarah B. Berman, David M. Holtzman, Chengjie Xiong, Randall J. Bateman, Eric Mcdade

Open Access Publications

Importance: The amyloid/tau/neurodegeneration (A/T/N) framework uses cerebrospinal fluid (CSF) levels of total tau (tTau) as a marker of neurodegeneration and CSF levels of phosphorylated tau 181 (pTau181) as a marker of tau tangles. However, it is unclear whether CSF levels of tTau and pTau181 have similar or different trajectories over the course of Alzheimer disease.

Objectives: To examine the rates of change in CSF levels of tTau and pTau181 across the Alzheimer disease course and how the rates of change are associated with brain atrophy as measured by magnetic resonance imaging.

Design, Setting, and Participants: This cohort study was set …


Toward A Metabolic Theory Of Life History, Joseph Robert Burger, Chen Hou, James H. Brown Dec 2019

Toward A Metabolic Theory Of Life History, Joseph Robert Burger, Chen Hou, James H. Brown

Biological Sciences Faculty Research & Creative Works

The life histories of animals reflect the allocation of metabolic energy to traits that determine fitness and the pace of living. Here, we extend metabolic theories to address how demography and mass-energy balance constrain allocation of biomass to survival, growth, and reproduction over a life cycle of one generation. We first present data for diverse kinds of animals showing empirical patterns of variation in life-history traits. These patterns are predicted by theory that highlights the effects of 2 fundamental biophysical constraints: demography on number and mortality of offspring; and mass-energy balance on allocation of energy to growth and reproduction. These …


Discrete Structure Of The Brain Rhythms, L. Perotti, J. Devito, D. Bessis, Y. Dabaghian Dec 2019

Discrete Structure Of The Brain Rhythms, L. Perotti, J. Devito, D. Bessis, Y. Dabaghian

Faculty Publications

Neuronal activity in the brain generates synchronous oscillations of the Local Field Potential (LFP). The traditional analyses of the LFPs are based on decomposing the signal into simpler components, such as sinusoidal harmonics. However, a common drawback of such methods is that the decomposition primitives are usually presumed from the onset, which may bias our understanding of the signal’s structure. Here, we introduce an alternative approach that allows an impartial, high resolution, hands-off decomposition of the brain waves into a small number of discrete, frequency-modulated oscillatory processes, which we call oscillons. In particular, we demonstrate that mouse hippocampal LFP contain …


The Logic Behind Neural Control Of Breathing Pattern, Alona Ben-Tal, Yunjiao Wang, Maria C.A. Leite Dec 2019

The Logic Behind Neural Control Of Breathing Pattern, Alona Ben-Tal, Yunjiao Wang, Maria C.A. Leite

Faculty Publications

The respiratory rhythm generator is spectacular in its ability to support a wide range of activities and adapt to changing environmental conditions, yet its operating mechanisms remain elusive. We show how selective control of inspiration and expiration times can be achieved in a new representation of the neural system (called a Boolean network). The new framework enables us to predict the behavior of neural networks based on properties of neurons, not their values. Hence, it reveals the logic behind the neural mechanisms that control the breathing pattern. Our network mimics many features seen in the respiratory network such as the …


Can Oral Contraceptives Increase Antibiotic Resistance In Escherichia Coli?, Allison Helene Clatch, Leah Van Otterloo Dec 2019

Can Oral Contraceptives Increase Antibiotic Resistance In Escherichia Coli?, Allison Helene Clatch, Leah Van Otterloo

Baker/Koob Endowments Awarded Projects

Antibiotic resistance is one of the most pressing threats to public health. Intrinsic resistance to many antimicrobials in Gram-negative bacteria is accomplished by naturally occurring efflux pumps. Efflux pumps are transmembrane proteins that can extrude antimicrobials from bacterial cytoplasm. Efflux pumps recognize a wide range of compounds including antibiotics, antiseptics, pesticides, and hormones. The upregulation of efflux pump genes in response to increasing concentrations of substrates has shown to increase resistance to toxic substrates. We hypothesize that efflux pump substrates other than antimicrobials, such as steroid hormones, will also induce the expression of efflux pump genes and consequently increase resistance …


Pacific Review Winter 2019, Alumni Association Of The University Of The Pacific Dec 2019

Pacific Review Winter 2019, Alumni Association Of The University Of The Pacific

Pacific Magazine and Pacific Review

No abstract provided.


Volume 2, Chapter 3-1: Slime Molds: Biology And Diversity, Janice M. Glime Dec 2019

Volume 2, Chapter 3-1: Slime Molds: Biology And Diversity, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


Volume 2, Chapter 3-4: Slime Molds: Ecology And Habitats - Lesser Habitats, Janice M. Glime Dec 2019

Volume 2, Chapter 3-4: Slime Molds: Ecology And Habitats - Lesser Habitats, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract 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 - #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 …