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A Review Of Baobab (Adansonia Digitata) Products: Effect Of Processing Techniques, Medicinal Properties And Uses, Donatien Kabore, Hagrétou Sawadogo-Lingani, Bréhima Diawara, Clarise Compaoré, Mamoudou H. Dicko Prof., Mogens Jacobsen Dec 2011

A Review Of Baobab (Adansonia Digitata) Products: Effect Of Processing Techniques, Medicinal Properties And Uses, Donatien Kabore, Hagrétou Sawadogo-Lingani, Bréhima Diawara, Clarise Compaoré, Mamoudou H. Dicko Prof., Mogens Jacobsen

Pr. Mamoudou H. DICKO, PhD

A general literature review including the effect of processing techniques, medicinal value and uses of baobab tree is reported in this manuscript. Baobab tree has multi-purpose uses, as it produces food and non-food products such as medicines, fuel, timber, fodder. Every part of the baobab tree is reported to be useful. The seeds, leaves, roots, flowers, fruit pulp and bark of baobab are edible. Baobab leaves are used in the preparation of soup. Seeds are used as a thickening agent in soups, but they can be fermented and used as a flavouring agent or roasted and eaten as snacks. The …


Natural Disease Resistance In Threatened Staghorn Corals, Steven V. Vollmer, David I. Kline Dec 2011

Natural Disease Resistance In Threatened Staghorn Corals, Steven V. Vollmer, David I. Kline

Steve Vollmer

Disease epidemics have caused extensive damage to tropical coral reefs and to the reef-building corals themselves, yet nothing is known about the abilities of the coral host to resist disease infection. Understanding the potential for natural disease resistance in corals is critically important, especially in the Caribbean where the two ecologically dominant shallow-water corals, Acropora cervicornis and A. palmata, have suffered an unprecedented mass die-off due to White Band Disease (WBD), and are now listed as threatened under the US Threatened Species Act and as critically endangered under the IUCN Red List criteria. Here we examine the potential for natural …


Genetic Diversity And Connectivity In The Threatened Staghorn Coral (Acropora Cervicornis) In Florida, Elizabeth M. Hemond, Steven V. Vollmer Dec 2011

Genetic Diversity And Connectivity In The Threatened Staghorn Coral (Acropora Cervicornis) In Florida, Elizabeth M. Hemond, Steven V. Vollmer

Steve Vollmer

Over the past three decades, populations of the dominant shallow water Caribbean corals, Acropora cervicornis and A. palmata, have been devastated by white-band disease (WBD), resulting in the listing of both species as threatened under the U.S. Endangered Species Act. A key to conserving these threatened corals is understanding how their populations are genetically interconnected throughout the greater Caribbean. Genetic research has demonstrated that gene flow is regionally restricted across the Caribbean in both species. Yet, despite being an important site of coral reef research, little genetic data has been available for the Florida Acropora, especially for the staghorn coral, …


Autotomy Of The Posterior Foot In Agaronia Propatula (Caenogastropoda: Olividae) Occurs In Animals That Are Fully Withdrawn Into Their Shells, Samantha D. Rupert, Winfried S. Peters Oct 2011

Autotomy Of The Posterior Foot In Agaronia Propatula (Caenogastropoda: Olividae) Occurs In Animals That Are Fully Withdrawn Into Their Shells, Samantha D. Rupert, Winfried S. Peters

Winfried S. Peters

This paper has no abstract; this is the first paragraph. Autotomy is the active shedding of a body part which occurs in a variety of emergency situations including attacks by predators (Stasek, 1967; McVean, 1975; Maginnis, 2006). The immediate advantage of autotomy – surviving an otherwise deadly attack – comes at a price, which may include physical, energetic, behavioural and reproductive costs (Cooper, 2003; Maginnis, 2006). While the evolutionary and ecological consequences of autotomy have been studied most thoroughly in lizards (Clause & Capaldi, 2006; Bateman & Fleming, 2009), the phenomenon also is known from numerous invertebrate taxa, where it …


Living More Than Just Enough For The City: Persistence Of High-Quality Vegetation In Natural Areas In An Urban Setting, Rebecca W. Dolan, Jessica D. Stephens, Marcia E. Moore Oct 2011

Living More Than Just Enough For The City: Persistence Of High-Quality Vegetation In Natural Areas In An Urban Setting, Rebecca W. Dolan, Jessica D. Stephens, Marcia E. Moore

Rebecca W. Dolan

Urban environments pose special challenges to flora, including altered disturbance regimes, habitat fragmentation, and increased opportunity for invasion by non-native species. In addition, urban natural area represents most people’s contact with nature, given the majority of the world’s population currently live in cities. We used coefficients of conservatism (C-values), a system that ranks species based on perceived fidelity to remnant native plant communities that retain ecological integrity, to quantify habitat quality of 14 sites covering 850 ha within the city of Indianapolis, Indiana, in the Midwestern United States. All sites contained significant natural area and were inventoried via intensive complete …


The Illusion Of Plenty: Hyperstability Masks Collapses In Two Recreational Fisheries That Target Fish Spawning Aggregations, Brad E. Erisman, Larry G. Allen, Jeremy T. Claisse, Daniel J. Pondella Ii, Eric F. Miller, Jason H. Murray Sep 2011

The Illusion Of Plenty: Hyperstability Masks Collapses In Two Recreational Fisheries That Target Fish Spawning Aggregations, Brad E. Erisman, Larry G. Allen, Jeremy T. Claisse, Daniel J. Pondella Ii, Eric F. Miller, Jason H. Murray

Daniel Pondella

Fisheries that target fish spawning aggregations can exhibit hyperstability, in which catch per unit effort (CPUE) remains elevated as stock abundance declines, but empirical support is limited. We compiled several fishery-dependent and fishery-independent data sets to assess stock trends in the barred sand bass (Paralabrax nebulifer) and the kelp bass (Paralabrax clathratus) in southern California, USA, evaluate the interaction between spawning aggregations and fishing activities, and test for hyperstability. Annual and seasonal trends from fisheries and population data indicate that regional stocks of both species have collapsed in response to overfishing of spawning aggregations and changes in environmental conditions. The …


Population Genetics Of An Ecosystem-Defining Reef Coral Pocillopora Damicornis In The Tropical Eastern Pacific, David J. Combosch, Steven V. Vollmer Sep 2011

Population Genetics Of An Ecosystem-Defining Reef Coral Pocillopora Damicornis In The Tropical Eastern Pacific, David J. Combosch, Steven V. Vollmer

Steve Vollmer

Background Coral reefs in the Tropical Eastern Pacific (TEP) are amongst the most peripheral and geographically isolated in the world. This isolation has shaped the biology of TEP organisms and lead to the formation of numerous endemic species. For example, the coral Pocillopora damicornis is a minor reef-builder elsewhere in the Indo-West Pacific, but is the dominant reef-building coral in the TEP, where it forms large, mono-specific stands, covering many hectares of reef. Moreover, TEP P. damicornis reproduces by broadcast spawning, while it broods mostly parthenogenetic larvae throughout the rest of the Indo-West Pacific. Population genetic surveys for P. damicornis …


Genetic Admixture In Multidimensional Niche Space: Asymmetrical Niche Similarity Promotes Gene Flow In Armadillos (Dasypus Novemcinctus), Maria Arteaga, John Mccormack, Luis Eguiarte, Rodrigo Medellín Aug 2011

Genetic Admixture In Multidimensional Niche Space: Asymmetrical Niche Similarity Promotes Gene Flow In Armadillos (Dasypus Novemcinctus), Maria Arteaga, John Mccormack, Luis Eguiarte, Rodrigo Medellín

John E. McCormack

We unite genetic data with a robust test of niche divergence to test the hypothesis that patterns of gene flow between two lineages of the nine-banded armadillo are influenced by their climatic niches. We collected Geographical Information System (GIS) data on climate using locality information from 111 individuals from two lineages that had associated genetic material. We tested whether niches of these lineages were more conserved or divergent than the background environments of their geographic ranges and found evidence for niche conservatism on two axes and no evidence for divergence on any axis. To address the role of niche similarity …


Extensive Clonal Spread And Extreme Longevity In Saw Palmetto, A Foundation Clonal Plant, Mizuki K. Takahashi, Liana M. Horner, Toshiro Kubota, Nathan A. Keller, Warren G. Abrahamson Ii Aug 2011

Extensive Clonal Spread And Extreme Longevity In Saw Palmetto, A Foundation Clonal Plant, Mizuki K. Takahashi, Liana M. Horner, Toshiro Kubota, Nathan A. Keller, Warren G. Abrahamson Ii

Warren G. Abrahamson, II

The lack of effective tools has hampered our ability to assess the size, growth and ages of clonal plants. With Serenoa repens (saw palmetto) as a model, we introduce a novel analytical frame work that integrates DNA fingerprinting and mathematical modelling to simulate growth and estimate ages of clonal plants. We also demonstrate the application of such life-history information of clonal plants to provide insight into management plans. Serenoa is an ecologically important foundation species in many Southeastern United States ecosystems; yet, many land managers consider Serenoa a troublesome invasive plant. Accordingly, management plans have been developed to reduce or …


Island Fragmentation Drives Evolutionary Diversification Of Galápagos Lava Lizards (Microlophus Spp.), Mark Jordan, H. Snell Jul 2011

Island Fragmentation Drives Evolutionary Diversification Of Galápagos Lava Lizards (Microlophus Spp.), Mark Jordan, H. Snell

Mark A. Jordan

No abstract provided.


Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan Jul 2011

Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan

Mark A. Jordan

The extent of evolutionary divergence of phenotypes between habitats is predominantly the result of the balance of differential natural selection and gene flow. Lava lizards (Microlophus albemarlensis) on the small island of Plaza Sur in the Galápagos archipelago inhabit contrasting habitats: dense vegetation on the western end of the island thins rapidly in a transitional area, before becoming absent on the eastern half. Associated with these habitats are phenotypic differences in traits linked to predator avoidance (increased wariness, sprint speed, and endurance in lizards from the sparsely vegetated habitat). This population provides an opportunity to test the hypothesis that reduced …


The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson Jul 2011

The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson

Mark A. Jordan

Forest loss and fragmentation is expected to shape the genetic structure of amphibian populations and reduce genetic variation. Another factor widely understood to have impacted these same parameters in North America is the range expansion that occurred following glacial retreat at the end of the Pleistocene. The Eastern Red-Backed Salamander (Plethodon cinereus) has been subjected to both processes. In this context, we investigated the historical events that are likely to have shaped genetic variation in this species using a panel of six microsatellite markers screened on individuals sampled across ten localities in northeastern Indiana, USA. We found low genetic diversity …


Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell Jul 2011

Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell

Mark A. Jordan

No abstract provided.


Species-Level Correlates Of Susceptibility To The Pathogenic Amphibian Fungus Batrachochytrium Dendrobatidis In The United States, Betsy Bancroft, Barbara Han, Catherine Searle, Lindsay Biga, Deanna Olson, Lee Kats, Joshua Lawler, Andrew Blaustein May 2011

Species-Level Correlates Of Susceptibility To The Pathogenic Amphibian Fungus Batrachochytrium Dendrobatidis In The United States, Betsy Bancroft, Barbara Han, Catherine Searle, Lindsay Biga, Deanna Olson, Lee Kats, Joshua Lawler, Andrew Blaustein

Lee Kats

Disease is often implicated as a factor in population declines of wildlife and plants. Understanding the characteristics that may predispose a species to infection by a particular pathogen can help direct conservation efforts. Recent declines in amphibian populations world-wide are a major conservation issue and may be caused in part by a fungal pathogen, Batrachochytrium dendrobatidis (Bd). We used Random Forest, a machine learning approach, to identify species-level characteristics that may be related to susceptibility to Bd. Our results suggest that body size at maturity, aspects of egg laying behavior, taxonomic order and family, and reliance on water are good …


Effects Of Management On Double-Crested Cormorant Nesting Colony Fidelity, Bronson K. Strickland, Brian S. Dorr, Fred Pogmore, Gary Nohrenberg, Scott C. Barras, John E. Mcconnell, John Gobeille May 2011

Effects Of Management On Double-Crested Cormorant Nesting Colony Fidelity, Bronson K. Strickland, Brian S. Dorr, Fred Pogmore, Gary Nohrenberg, Scott C. Barras, John E. Mcconnell, John Gobeille

Brian S Dorr

No abstract provided.


Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Matricaria Chamomilla L. From Djibouti, Fatouma M. Abdoul-Latif, Mohamed Nabil, Prosper Edou, Adwa A. Ali, Samatar O. Djama, Louis-Clément Obamé, Mamoudou H. Dicko Prof. May 2011

Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Matricaria Chamomilla L. From Djibouti, Fatouma M. Abdoul-Latif, Mohamed Nabil, Prosper Edou, Adwa A. Ali, Samatar O. Djama, Louis-Clément Obamé, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The essential oil and methanol extracts of Matricaria Chamomilla L. were subjected to screening for their possible antioxidant activity by two complementary test systems, namely 2,2-diphenykpicrylhydrazyl (DPPH) free radical scavenging and β-carotene-linoleic acid assays. BHT was used as positive control in both test systems. In the DPPH test system, the IC50 values of essential oil and methanol extracts were 4.18 and 1.83 μg/ml, respectively. In the β-carotene-linoleic acid system, oxidation was effectively inhibited by M. Chamomilla, the RAA value of essential oil and methanol extracts were 12.69 and 11.37 %, respectively. When compared to BHT, the essential oil and methanol …


New Phylogenetic Information Suggests Both An Increase And At Least One Loss Of Cooperative Breeding During The Evolutionary History Of Aphelocoma Jays, Elena Berg, Robert Aldredge, A. Peterson, John Mccormack Apr 2011

New Phylogenetic Information Suggests Both An Increase And At Least One Loss Of Cooperative Breeding During The Evolutionary History Of Aphelocoma Jays, Elena Berg, Robert Aldredge, A. Peterson, John Mccormack

John E. McCormack

Efforts to identify ecological and life history factors associated with cooperative breeding have been largely unsuccessful, and interest is growing in the role of phylogenetic history in determining the distribution of this social system among lineages. In birds, cooperative breeding is distributed non-randomly among lineages, suggesting that phylogenetic inertia may play an important role in determining its distribution. The bird genus Aphelocoma has been particularly well studied because, although it is a relatively small genus, it shows broad among-lineage variation in level of cooperation. Previous analyses described an unusual unidirectional pattern of evolutionary loss of cooperation in Aphelocoma. Here, historical …


Population Growth Of Mexican Free-Tailed Bats (Tadarida Brasiliensis Mexicana) Predates Human Agricultural Activity, Amy L. Russell, Murray P. Cox, Veronica A. Brown, Gary F. Mccracken Mar 2011

Population Growth Of Mexican Free-Tailed Bats (Tadarida Brasiliensis Mexicana) Predates Human Agricultural Activity, Amy L. Russell, Murray P. Cox, Veronica A. Brown, Gary F. Mccracken

Amy L. Russell

Background: Human activities, such as agriculture, hunting, and habitat modification, exert a significant effect on native species. Although many species have suffered population declines, increased population fragmentation, or even extinction in connection with these human impacts, others seem to have benefitted from human modification of their habitat. Here we examine whether population growth in an insectivorous bat (Tadarida brasiliensis mexicana) can be attributed to the widespread expansion of agriculture in North America following European settlement. Colonies of T. b. mexicana are extremely large (~106 individuals) and, in the modern era, major agricultural insect pests form an important component of their …


Adaptation As Process: The Future Of Darwinism And The Legacy Of Theodosius Dobzhansky, David Depew Feb 2011

Adaptation As Process: The Future Of Darwinism And The Legacy Of Theodosius Dobzhansky, David Depew

David J Depew

Conceptions of adaptation have varied in the history of genetic Darwinism depending on whether what is taken to be focal is the process of adaptation, adapted states of populations, or discrete adaptations in individual organisms. I argue that Theodosius Dobzhansky’s view of adaptation as a dynamical process contrasts with so-called “adaptationist” views of natural selection figured as “design-without-a-designer” of relatively discrete, enumerable adaptations. Correlated with these respectively process and product oriented approaches to adaptive natural selection are divergent pictures of organisms themselves as developmental wholes or as “bundles” of adaptations. While even process versions of genetical Darwinism are insufficiently sensitive …


The Complexity Of Amphibian Population Declines: Understanding The Role Of Cofactors In Driving Amphibian Losses, Andrew Blaustein, Barbara Han, Rick Relyea, Pieter Johnson, Julia Buck, Stephanie Gervasi, Lee Kats Feb 2011

The Complexity Of Amphibian Population Declines: Understanding The Role Of Cofactors In Driving Amphibian Losses, Andrew Blaustein, Barbara Han, Rick Relyea, Pieter Johnson, Julia Buck, Stephanie Gervasi, Lee Kats

Lee Kats

Population losses and extinctions of species are occurring at unprecedented rates, as exemplified by declines and extinctions of amphibians worldwide. However, studies of amphibian population declines generally do not address the complexity of the phenomenon or its implications for ecological communities, focusing instead on single factors affecting particular amphibian species. We argue that the causes for amphibian population declines are complex; may differ among species, populations, and life stages within a population; and are context dependent with multiple stressors interacting to drive declines. Because amphibians are key components of communities, we emphasize the importance of investigating amphibian declines at the …


Exploring Demographic, Physical, And Historical Explanations For The Genetic Structure Of Two Lineages Of Greater Antillean Bats, Robert A. Muscarella, Kevin L. Murray, Derek Ortt, Amy L. Russell, Theodore H. Fleming Feb 2011

Exploring Demographic, Physical, And Historical Explanations For The Genetic Structure Of Two Lineages Of Greater Antillean Bats, Robert A. Muscarella, Kevin L. Murray, Derek Ortt, Amy L. Russell, Theodore H. Fleming

Amy L. Russell

Observed patterns of genetic structure result from the interactions of demographic, physical, and historical influences on gene flow. The particular strength of various factors in governing gene flow, however, may differ between species in biologically relevant ways. We investigated the role of demographic factors (population size and sex-biased dispersal) and physical features (geographic distance, island size and climatological winds) on patterns of genetic structure and gene flow for two lineages of Greater Antillean bats. We used microsatellite genetic data to estimate demographic characteristics, infer population genetic structure, and estimate gene flow among island populations of Erophylla sezekorni/E. bombifrons and Macrotus …


Description Of The Tadpoles Of Hypsiboas Aguilari And H. Melanopleura Aguilari And H. Melanopleura (Anura: Hylidae: Hypsiboas Pulchellus Group), Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer Feb 2011

Description Of The Tadpoles Of Hypsiboas Aguilari And H. Melanopleura Aguilari And H. Melanopleura (Anura: Hylidae: Hypsiboas Pulchellus Group), Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer

Edgar Lehr

We describe the tadpoles of Hypsiboas melanopleura and H. aguilari and compare them with the tadpoles of other species in the Hypsiboas pulchellus group. The description of the tadpole of H. aguilari is based on an individual at Gosner Stage 29 and that of H. melanopleura on an individual at Gosner Stage 28. Both tadpoles have a labial tooth row formula of 2(2)/4(1). At Stage 35, the tadpole of H. aguilari had a total length of 52.2 mm, at Stage 37, the tadpole of H. melanopleura had a total length of 60.7 mm. In life, the tadpole of H. aguilari …


Biodepollution Of Wastewater Containing Phenolic Compounds From Leather Industry By Plant Peroxidases, Mamounata Diao, Nafissetou Ouedraogo, Lamine Baba-Moussa, Paul W. Savadogo, Georges N'Guessan Amani, Mamoudou H. Dicko Prof. Jan 2011

Biodepollution Of Wastewater Containing Phenolic Compounds From Leather Industry By Plant Peroxidases, Mamounata Diao, Nafissetou Ouedraogo, Lamine Baba-Moussa, Paul W. Savadogo, Georges N'Guessan Amani, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

This study deals with the use of peroxidases (POXs) from Allium sativum, Ipomoea batatas, Raphanus sativus and Sorghum bicolor to catalyze the degradation of free phenolic compounds as well as phenolic compounds contained in wastewater from leather industry. Secretory plant POXs were able to catalyze the oxidation of gallic acid, ferulic acid, 4-hydroxybenzoic acid, pyrogallol and 1,4-tyrosol prepared in ethanol 2% (v:v). Efficiency of peroxidase catalysis depends strongly on the chemical nature of phenolic substrates and on the botanical source of the enzymes. It appeared that POX from Raphanus sativus had the highest efficiency. Results show that POXs can also …


Reduced Mhc And Neutral Variation In The Galápagos Hawk, An Island Endemic, Jennifer L. Bollmer, Joshua M. Hull, Holly B. Ernest, José H. Sarasola, Patricia G. Parker Jan 2011

Reduced Mhc And Neutral Variation In The Galápagos Hawk, An Island Endemic, Jennifer L. Bollmer, Joshua M. Hull, Holly B. Ernest, José H. Sarasola, Patricia G. Parker

Patricia Parker

Background
Genes at the major histocompatibility complex (MHC) are known for high levels of polymorphism maintained by balancing selection. In small or bottlenecked populations, however, genetic drift may be strong enough to overwhelm the effect of balancing selection, resulting in reduced MHC variability. In this study we investigated MHC evolution in two recently diverged bird species: the endemic Galápagos hawk (Buteo galapagoensis), which occurs in small, isolated island populations, and its widespread mainland relative, the Swainson's hawk (B. swainsoni).

Results
We amplified at least two MHC class II B gene copies in each species. We recovered only three different sequences …


Intracellular Invasion Of Green Algae In A Salamander Host, Ryan Kerney, Eunsoo Kim, Roger Hangater, Aaron Heiss, Cory Bishop, Brian Hall Dec 2010

Intracellular Invasion Of Green Algae In A Salamander Host, Ryan Kerney, Eunsoo Kim, Roger Hangater, Aaron Heiss, Cory Bishop, Brian Hall

Ryan Kerney

The association between embryos of the spotted salamander (Ambystoma maculatum) and green algae (“Oophila amblystomatis” Lamber ex Printz) has been considered an ectosymbiotic mutualism. We show here, however, that this symbiosis is more intimate than previously reported. A combination of imaging and algal 18S rDNA amplification reveals algal invasion of embryonic salamander tissues and cells during development. Algal cells are detectable from embryonic and larval Stages 26–44 through chlorophyll autofluorescence and algal 18S rDNA amplification. Algal cell ultrastructure indicates both degradation and putative encystment during the process of tissue and cellular invasion. Fewer algal cells were detected in later-stage larvae …


Symbioses Between Salamander Embryos And Green Algae, Ryan Kerney Dec 2010

Symbioses Between Salamander Embryos And Green Algae, Ryan Kerney

Ryan Kerney

The symbiosis between Ambystoma maculatum (spotted salamander) embryos and green algae was initially described over 120 years ago. Algae populate the egg capsules that surround individual A. maculatum embryos, giving the intracapsular fluid a characteristic green hue. Early work established this symbiosis to be a mutualism, while subsequent studies sought to identify the material benefits of this association to both symbiont and host. These studies have shown that salamander embryos benefit from increased oxygen concentrations provided by their symbiotic algae. The algae, in turn, may benefit from ammonia excreted by the embryos. All of these early studies considered the associ- …


Molecular Anatomy Of The Developing Limb In The Coqu ́I Frog, Eleutherodactylus Coqui, Joshua Gross, Ryan Kerney, James Hanken, Clifford Tabin Dec 2010

Molecular Anatomy Of The Developing Limb In The Coqu ́I Frog, Eleutherodactylus Coqui, Joshua Gross, Ryan Kerney, James Hanken, Clifford Tabin

Ryan Kerney

The vertebrate limb demonstrates remark- able similarity in basic organization across phylogenetically disparate groups. To gain further insight into how this mor- phological similarity is maintained in different developmental contexts, we explored the molecular anatomy of size-reduced embryos of the Puerto Rican coqu ́ı frog, Eleutherodactylus coqui. This animal demonstrates direct development, a life- history strategy marked by rapid progression from egg to adult and absence of a free-living, aquatic larva. Nonethe- less, coqu ́ı exhibits a basal anuran limb structure, with four toes on the forelimb and five toes on the hind limb. We in- vestigated the extent to …


Plant-Animal Interactions, W. Abrahamson, T. Taylor Dec 2010

Plant-Animal Interactions, W. Abrahamson, T. Taylor

Warren G. Abrahamson, II

No abstract provided.


Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney Dec 2010

Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney

Ryan Kerney

The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and …


Calibrating Divergence Times On Species Tree Versus Gene Trees: Implications For Speciation History Of Aphelocoma Jays, John Mccormack, Joseph Heled, Kathleen Delaney, A. Peterson, L. Knowles Dec 2010

Calibrating Divergence Times On Species Tree Versus Gene Trees: Implications For Speciation History Of Aphelocoma Jays, John Mccormack, Joseph Heled, Kathleen Delaney, A. Peterson, L. Knowles

John E. McCormack

Estimates of the timing of divergence are central to testing the underlying causes of speciation. Relaxed molecular clocks and fossil calibration have improved these estimates; however, these advances are implemented in the context of gene trees, which can overestimate divergence times. Here we couple recent innovations for dating speciation events with the analytical power of species trees, where multilocus data are considered in a coalescent context. Divergence times are estimated in the bird genus Aphelocoma to test whether speciation in these jays coincided with mountain uplift or glacial cycles. Gene trees and species trees show general agreement that diversification began …