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Full-Text Articles in Life Sciences

Reflections On Plant And Soil Nematode Ecology: Past, Present And Future, Howard Ferris, Bryan S. Griffiths, Dorota L. Porazinska, Thomas O. Powers, Koon-Hui Wang, Mario Tenuta Jan 2012

Reflections On Plant And Soil Nematode Ecology: Past, Present And Future, Howard Ferris, Bryan S. Griffiths, Dorota L. Porazinska, Thomas O. Powers, Koon-Hui Wang, Mario Tenuta

Department of Plant Pathology: Faculty Publications

The purpose of this review is to highlight key developments in nematode ecology from its beginnings to where it stands today as a discipline within nematology. Emerging areas of research appear to be driven by crop production constraints, environmental health concerns, and advances in technology. In contrast to past ecological studies which mainly focused on management of plant-parasitic nematodes, current studies reflect differential sensitivity of nematode faunae. These differences, identified in both aquatic and terrestrial environments include response to stressors, environmental conditions, and management practices. Methodological advances will continue to influence the role nematodes have in addressing the nature of …


Impacts Of Urbanisation On The Native Avifauna Of Perth, Western Australia, Robert A. Davis, Cheryl Gole, J Dale Roberts Jan 2012

Impacts Of Urbanisation On The Native Avifauna Of Perth, Western Australia, Robert A. Davis, Cheryl Gole, J Dale Roberts

Research outputs 2013

Urban development either eliminates, or severely fragments, native vegetation, and therefore alters the distribution and abundance of species that depend on it for habitat. We assessed the impact of urban development on bird communities at 121 sites in and around Perth, Western Australia. Based on data from community surveys, at least 83 % of 65 landbirds were found to be dependent, in some way, on the presence of native vegetation. For three groups of species defined by specific patterns of habitat use (bushland birds), there were sufficient data to show that species occurrences declined as the landscape changed from variegated …


Grts And Graphs: Monitoring Natural Resources In Urban Landscapes, Todd R. Lookingbill, John Paul Schmit, Shawn L. Carter Jan 2012

Grts And Graphs: Monitoring Natural Resources In Urban Landscapes, Todd R. Lookingbill, John Paul Schmit, Shawn L. Carter

Geography and the Environment Faculty Publications

Environmental monitoring programs are an important tool for providing land managers with a scientific basis for management decisions. However, many ecological processes operate on spatial scales that transcend management boundaries (Schonewald-Cox 1988). For example, adjacent lands may influence protected-area resources via edge effects, source-sink dynamics, or invasion processes (Jones et al. 2009). Hydrologic alterations outside management units also may have profound effects on the integrity of resources being managed (Pringle 2000). The impacts of climate change are presenting challenges to resource management at local-to-global scales (Karl et al. 2009). This potential disparity between ecological and political boundaries presents an interesting …


The Collie Pit Lake District, Western Australia: An Overview, Mark Lund, C. D. Mccullough, Naresh Radhakrishnan Jan 2012

The Collie Pit Lake District, Western Australia: An Overview, Mark Lund, C. D. Mccullough, Naresh Radhakrishnan

Research outputs 2012

Open-cut mining can create pit lakes that form distinct lake districts. Localised factors at the lake level ensure that individual pit lakes develop different water qualities and ecological values. The Collie Lake District is formed from open cut coal mining operations in the south-west of Western Australia. The limnology and water quality of 13 of these lakes were investigated in 2009. All of the deep pit lakes appeared to be thermally stratified over the summer but many had, or were close to, mixing by autumn. The lakes were mainly Al buffered, with pH ranging from 2.5 to 6.4. Most lakes …


Impacts Of Urbanisation On The Native Avifauna Of Perth, Western Australia, Robert Davis, C Gole, Jd Roberts Jan 2012

Impacts Of Urbanisation On The Native Avifauna Of Perth, Western Australia, Robert Davis, C Gole, Jd Roberts

Research outputs 2012

Urban development either eliminates, or severely fragments, native vegetation, and therefore alters the distribution and abundance of species that depend on it for habitat. We assessed the impact of urban development on bird communities at 121 sites in and around Perth, Western Australia. Based on data from community surveys, at least 83 % of 65 landbirds were found to be dependent, in some way, on the presence of native vegetation. For three groups of species defined by specific patterns of habitat use (bushland birds), there were sufficient data to show that species occurrences declined as the landscape changed from variegated …


No Honor Among Snails: Conspecific Competition Leads To Incomplete Drill Holes In The Naticid Gastropod Neverita Delessertiana (R Cluz), Jack A. Hutchings Jan 2012

No Honor Among Snails: Conspecific Competition Leads To Incomplete Drill Holes In The Naticid Gastropod Neverita Delessertiana (R Cluz), Jack A. Hutchings

USF Tampa Graduate Theses and Dissertations

The fossil record of drilling predation has been widely used to study predator-prey interactions and their relative importance on long-term evolutionary processes. Incomplete drill holes have been interpreted as indicators of failed attacks due to well-defended prey. However, this interpretation is based on pair-wise interactions between one predator and one prey, a condition commonly compromised in nature. The hypothesis that interference among drilling predators leads to an increase in the relative frequency of incomplete drill holes was tested in the laboratory using the naticid Neverita delessertiana (R cluz) and a common prey, the bivalve Chione elevata (Say). The experiment consisted …


Bacterial Community Structure Of Contrasting Soils Underlying Bornean Rain Forests: Inferences From Microarray And Next-Generation Sequencing Methods, Sabrina E. Russo, Ryan Legge, Karrie A. Weber, Eoin L. Brodie, Katherine C. Goldfarb, Andrew K. Benson, Sylvester Tan Jan 2012

Bacterial Community Structure Of Contrasting Soils Underlying Bornean Rain Forests: Inferences From Microarray And Next-Generation Sequencing Methods, Sabrina E. Russo, Ryan Legge, Karrie A. Weber, Eoin L. Brodie, Katherine C. Goldfarb, Andrew K. Benson, Sylvester Tan

School of Biological Sciences: Faculty Publications

Soil microbial diversity is vast, and we lack even basic understanding of how this diversity is distributed ecologically. Using pyrosequencing and microarray methods, we quantified the structure of bacterial communities in two contrasting soils underlying Bornean rain forest (clay and sandy loam) that differ markedly in soil properties, aboveground tree flora, and leaf litter decomposition rates. We found significant soil-related taxonomic and phylogenetic differences between communities that, due to their proximity, are independent of climate. Bacterial communities showed distinct compositional and taxon-abundance distributions that were significantly correlated with the structure of the overlying tree community. Richness of bacteria was greater …


Brown Treesnakes: A Potential Invasive Species For The United States, Samantha Sue Kahl, Scott E. Henke, Marc A. Hall, David K. Britton Jan 2012

Brown Treesnakes: A Potential Invasive Species For The United States, Samantha Sue Kahl, Scott E. Henke, Marc A. Hall, David K. Britton

Human–Wildlife Interactions

Brown treesnakes (ˆ) are mildly venomous, exotic snakes that have the potential to become an invasive species in North America, Hawaii, and the Commonwealth of the Northern Mariana Islands. The snake is native to northern and eastern Australia, New Guinea, and other islands of northern and western Melanesia. The snakes were first found outside their native range on Guam in 1953. The exact date they reached the island is uncertain, but they are believed to have arrived on military cargo transport vessels some time during or just after World War II. During the years that followed, the population of brown …


Epiphytic Lichen Diversity On Quercus Cerris And Q. Frainetto In The Marmara Region (Turkey), Seyhan Oran, Şule Öztürk Jan 2012

Epiphytic Lichen Diversity On Quercus Cerris And Q. Frainetto In The Marmara Region (Turkey), Seyhan Oran, Şule Öztürk

Turkish Journal of Botany

The epiphytic diversity of lichens associated with Quercus cerris L. and Quercus frainetto Ten. were investigated in 21 localities of the Marmara region. A total of 106 taxa belonging to 49 genera were reported on Q. cerris and Q. frainetto, and 16 of those taxa were recorded for the first time in the Marmara region. The number of lichen species found on Q. cerris was 83, while 85 taxa were found on Q. frainetto. Several differences regarding the lichen taxa were found in these 2 oaks species even though they were growing in the same habitat and in the same …


The Management Of Feral Pig Socio-Ecological Systems In Far North Queensland, Australia, Gabriela Shuster Jan 2012

The Management Of Feral Pig Socio-Ecological Systems In Far North Queensland, Australia, Gabriela Shuster

Antioch University Dissertations & Theses

The development of management programs for socio-ecological systems that include multiple stakeholders is a complex process and requires careful evaluation and planning. This is particularly a challenge in the presence of intractable conflict. The feral pig (Sus scrofa) in Australia is part of one such socio-ecological system. There is a large and heterogeneous group of stakeholders interested in pig management. Pigs have diverse effects on wildlife and plant ecology, economic, health, and social sectors. This study used the feral pig management system as a vehicle to examine intractable conflict in socio-ecological systems. The purpose of the study was …


Rodent Burrow Systems In North America: Problems Posed And Potential Solutions, Gary W. Witmer, Rachael S. Moulton, Jenna L. Swartz Jan 2012

Rodent Burrow Systems In North America: Problems Posed And Potential Solutions, Gary W. Witmer, Rachael S. Moulton, Jenna L. Swartz

United States Department of Agriculture Wildlife Services: Staff Publications

Many rodent species are effective burrowers. In North America, these include species of ground squirrels, prairie dogs, marmots, and pocket gophers. The burrow systems of other species of rodents such as voles and mice are less elaborate and pose less potential for direct damage. Burrowing abilities, coupled with other characteristics (e.g., prolific, adaptable, ever-growing incisors for gnawing), can result in many types and amounts of impacts to human resources and ecosystems. Damage occurs to levees, roadbeds, buried pipes and cables, intrusion to sensitive areas (such as military sites, capped hazardous waste burial sites), vegetation effects, effects on water infiltration/runoff, and …


A Survey Of The Ants (Hymenoptera: Formicidae) Of Arkansas And The Ozark Mountains, Joseph O'Neill Dec 2011

A Survey Of The Ants (Hymenoptera: Formicidae) Of Arkansas And The Ozark Mountains, Joseph O'Neill

Horticulture Undergraduate Honors Theses

Ants are among the most abundant animals in most terrestrial ecosystems, yet local fauna are often poorly understood due to a lack of surveys. This study separated and identified ant species from arthropod samples obtained during ongoing projects by the lab of Dr. A.P.G. Dowling, Professor of Entomology at the University of Arkansas. More than 600 ants were prepared, 284 of which were identified to genus and 263 to species. From this collection, 33 species and one morphospecies were identified, comprising 18 genera in total. Additionally, 28 new distributional records were recorded for Benton, Madison, Newton, and Washington Counties in …


Population Status, Habitat Dependence, And Reproductive Ecology Of Bahama Orioles: A Critically Endangered Synanthropic Species, Melissa R. Price, Valerie A. Lee, William K. Hayes Dec 2011

Population Status, Habitat Dependence, And Reproductive Ecology Of Bahama Orioles: A Critically Endangered Synanthropic Species, Melissa R. Price, Valerie A. Lee, William K. Hayes

Faculty Works

Recent elevation of critically endangered Bahama Orioles (Icterus northropi) to species status prompted us to evaluate their population status, habitat use, and breeding ecology. From surveys, we estimated that at least 141 to 254 individuals remain globally, with 90 to 162, 24 to 44, and 27 to 48 individuals remaining on North Andros Island, Mangrove Cay, and South Andros Island, The Bahamas, respectively. Orioles were observed nesting exclusively in anthropogenic habitat (residential and agricultural land), but home ranges also included nearby pine forest and coppice (dry broadleaf forest). Most nests (40 of 46, or 87%) were in nonnative coconut palm …


The Evolution Of Lateralized Foot Use In Parrots: A Phylogenetic Approach, Culum Brown, Maria Magat Nov 2011

The Evolution Of Lateralized Foot Use In Parrots: A Phylogenetic Approach, Culum Brown, Maria Magat

Sentience Collection

Cerebral lateralization refers to the division of cognitive function in either brain hemisphere and may be overtly expressed as behavioral asymmetries, such as handedness. The evolutionary history of laterality is of considerable interest due to its close link with the development of human language. Although considerable research effort has aimed at the proximate explanations of cerebral lateralization, considerably less attention has been paid to ultimate explanations. The extent to which laterality is constrained by phylogeny or shaped by ecological forces through natural selection has received little attention. Here, the foot preference of 23 species of Australian parrots was examined to …


Gravesoil Microbial Community Structure During Carcass Decomposition, Amy E. Maile Nov 2011

Gravesoil Microbial Community Structure During Carcass Decomposition, Amy E. Maile

Department of Entomology: Dissertations, Theses, and Student Research

Dead bodies placed on soil represent unique challenges for investigators. Although processes in soils can be used to estimate postmortem interval, we know very little about how carcasses and insects affect gravesoil microbial communities.

To address this, the current project was composed of two experiments. Experiment one was conducted to investigate the effect of surface type on carcass decomposition and evaluate soil ecology methods. Experiment two was conducted to investigate the presence of an insect population (Lucilia sericata Meigen) on gravesoil microbial communities. Both experiments were conducted in a laboratory setting using freshly killed mouse carcasses. Mouse carcasses were …


Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas Oct 2011

Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas

Climate Change Seminar Series (NNE)

Hydroecology: the interface of ecological systems and water which combines the scientific disciplines of hydrology and ecology

Goal: evaluate the hydrologic and climate history using pollen, loss on ignition, total inorganic carbon, and invertebrates from spring sediments in Spring Valley, Eastern Nevada and Snake Valley, Western Utah


Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida Aug 2011

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …


Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten Aug 2011

Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten

All Dissertations

Zoos are a unique environment where humans and animals are in close daily contact, potential mosquito habitats exist, exotic plants and animals are introduced regularly, and wild animals roam. Studies of mosquito behaviors in zoos will lead to a better understanding, both within and outside zoos, of disease transmission routes and mosquito biology. To investigate whether the unique assemblage of habitats in zoos affects mosquito behavior, I sampled larvae and adults in the Greenville Zoo and the Riverbanks Zoo, South Carolina, USA, from March 2008 to January 2011. The objectives of my study were to investigate mosquito oviposition behavior, blood-host …


The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris Jul 2011

The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …


Human-Wildlife Conflict On Small, Subsistence Farms In Kenya, Christopher B. Colonna May 2011

Human-Wildlife Conflict On Small, Subsistence Farms In Kenya, Christopher B. Colonna

Mahurin Honors College Capstone Experience/Thesis Projects

As human populations expand, wildlife suddenly competes with humans for resources and confrontation arises as a result. Rural Africa is typical of this problem. We surveyed local owners of small farms within the five villages surrounding Mount Kasigau in Southeast Kenya to quantify losses due to wildlife depredation on both subsistence and cash crops as well as to discover the patterns and variables influencing farmer-wildlife confrontations in the region. We found no statistically significant correlations among the value of damage per acre, the distance from the bush, or the distance to the nearest water source. We did find statistical significance …


Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost May 2011

Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost

Theses and Dissertations

It is important to understand mechanisms that facilitate expansion of two common shrubs, Morella cerifera and Baccharis halimifolia in coastal environments. The purpose of my study was to investigate the physiological and structural changes that occur as leaves age. Photosynthesis, incident light, chlorophyll, and leaf C:N ratios were quantified for young, intermediate, and old leaves (distal, central and proximal leaves, respectively). Leaf structural differences were also compared. Leaves did not change morphologically with age. Light decreased with leaf age and during winter months. Photosynthesis showed no seasonal or age related patterns. Chlorophyll increased initially and then declined with age due …


Sponges Of The Caribbean: Linking Sponge Morphology And Associated Bacterial Communities, Ericka Ann Poppell May 2011

Sponges Of The Caribbean: Linking Sponge Morphology And Associated Bacterial Communities, Ericka Ann Poppell

Master's Theses

The ecological and evolutionary relationship between sponges and their symbiotic microflora remains poorly understood, which limits our ability to understand broad scale patterns in benthic-pelagic coupling on coral reefs. Previous research classified sponges into two different categories of sponge microbial associations: High Microbial Abundance (HMA) and Low Microbial Abundance (LMA) sponges. Choanocyte chamber morphology and density was characterized in representatives of HMA and LMA sponges using scanning electron microscopy from freeze-fractured tissue. Denaturing Gradient Gel Elextrophoresis was used to examine taxonomic differences among the bacterial communities present in a variety of tropical sponges. The results supported the hypothesis that choanocyte …


Epigeic Spider (Araneae) Diversity And Habitat Distributions In Kings Mountain National Military Park, South Carolina, Sarah Stellwagen May 2011

Epigeic Spider (Araneae) Diversity And Habitat Distributions In Kings Mountain National Military Park, South Carolina, Sarah Stellwagen

All Theses

This study examined the epigeic spider fauna in Kings Mountain National Military Park. The aim of this study is to make this information available to park management for use in the preservation of natural resources. Pitfall trapping was conducted monthly for one year in three distinct habitats: riparian, forest, and ridge-top. The study was conducted from August 2009 to July 2010. One hundred twenty samples were collected in each site. Overall, 289 adult spiders comprising 66 species were collected in the riparian habitat, 345 adult comprising 57 species were found in the forest habitat, and 240 adults comprising 47 species …


Wood Anatomy Of Family Salvadoraceae From The Indian Subcontinent With Special Reference To The Ultrastructure Of The Vessel Wall, Vishakha Saxena, Sangeeta Gupta Mar 2011

Wood Anatomy Of Family Salvadoraceae From The Indian Subcontinent With Special Reference To The Ultrastructure Of The Vessel Wall, Vishakha Saxena, Sangeeta Gupta

Aliso: A Journal of Systematic and Floristic Botany

The present study describes the wood microstructure of Azima tetracantha, Salvadora oleoides, and S. persica, the members of family Salvadoraceae represented in the Indian Subcontinent. An identification key based on wood anatomical features has been developed for the separation of the species. SEM studies revealed the presence of vesturing in intervessel pits of Salvadora.


The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2011

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

During the fall of 2011, the Colby Environmental Assessment Team (CEAT) studied the Serpentine connecting East Pond and North Pond. East and North Ponds are members of the larger seven-lake system known as the Belgrade Lakes, located in central Maine. There are over 5,500 lakes in Maine that contribute $6.7 billion to the economy annually through activities including boating, fishing, swimming etc. Additionally, Maine’s lakes are sources of municipal and agricultural water, act as flood buffers, and host a wide range of plant, animal, and fish life. Lakes in Maine are a crucial part society and should be studied and …


Advertisement Call And Distribution Of The Treefrogs Hyla Chrysoscelis And Hyla Versicolor In Virginia, Joseph C. Mitchell, Christopher A. Pague Jan 2011

Advertisement Call And Distribution Of The Treefrogs Hyla Chrysoscelis And Hyla Versicolor In Virginia, Joseph C. Mitchell, Christopher A. Pague

Virginia Journal of Science

The gray treefrog complex consists of two sibling species that are indistinguishable morphologically, the diploid Hyla chrysoscelis and the tetraploid Hyla versicolor. Identification is possible in the field only by audio recognition of male advertisement call trill rates (pulses/second). During 1979-1983 we evaluated taped calls of these two species taken from 89 populations from throughout Virginia to map their respective ranges and to evaluate differences in call parameters. Hyla chrysoscelis occurs in the Coastal Plain, eastern and southern Piedmont, and in southwestern Virginia. Hyla versicoloroccurs in the Piedmont, Blue Ridge, and Ridge and Valley regions south to Wythe …


Quantitatively Measuring In Situ Flows Using A Self-Contained Underwater Velocimetry Apparatus (Scuva), Kakani Katija, Sean Colin, John H. Costello, John O. Dabiri Jan 2011

Quantitatively Measuring In Situ Flows Using A Self-Contained Underwater Velocimetry Apparatus (Scuva), Kakani Katija, Sean Colin, John H. Costello, John O. Dabiri

Arts & Sciences Faculty Publications

The ability to directly measure velocity fields in a fluid environment is necessary to provide empirical data for studies in fields as diverse as oceanography, ecology, biology, and fluid mechanics. Field measurements introduce practical challenges such as environmental conditions, animal availability, and the need for field-compatible measurement techniques. To avoid these challenges, scientists typically use controlled laboratory environments to study animal-fluid interactions. However, it is reasonable to question whether one can extrapolate natural behavior (i.e., that which occurs in the field) from laboratory measurements. Therefore, in situ quantitative flow measurements are needed to accurately describe animal swimming in their natural …


Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North Jan 2011

Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North

Environmental Sustainability Books

Jointly sponsored by the Hoffman Environmental Research Institute, the National Cave & Karst Research Institute, and the International Association of Hydrogeologists, the 2011 International Conference on Karst Hydrogeology and Ecosystems was held at Western Kentucky University in Bowling Green, Kentucy on 8-10 June 2011. Topics include karst geomorphology, engineering and modeling, isotope geochemistry, and cultural and educational aspects of karst environments.


Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva Jan 2011

Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva

Open Access Theses & Dissertations

The Rock Rattlesnake, Crotalus lepidus is a small species that is found from southern Arizona, southern New Mexico, and southern Texas, in the U.S., into northern Mexico. To date, little is known about the ecology of this species. Ecological information is becoming desperately needed for supporting the conservation and protection of species living in fragile environments such as the Chihuahuan Desert amid current local and global threats (e.g., habitat destruction and modification, urban development, and climate change). Although rattlesnakes spend a significant amount of time underground while overwintering, little is known about the physiology and behavior of these organisms during …


On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham Jan 2011

On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham

Biology Faculty Publications

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power-laws using linear regression on log-transformed data (LR) has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations we demonstrate that the error distribution determines which method performs better, with LR better characterizing data with multiplicative lognormal error and NLR better characterizing data with additive, homoscedastic, normal error. Analysis of 471 biological power-laws shows that both …