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Small-Scale Divergence In Egg Color Along An Elevation Gradient In The Mexican Jay (Aphelocoma Ultramarina): A Condition-Dependent Response?, John Mccormack, Elena Berg Dec 2009

Small-Scale Divergence In Egg Color Along An Elevation Gradient In The Mexican Jay (Aphelocoma Ultramarina): A Condition-Dependent Response?, John Mccormack, Elena Berg

John E. McCormack

The functional significance of bird egg color and patterning is a continuing subject of interest and debate. Extreme polymorphism in eggshell appearance is often thought to be maintained by frequency-dependent selection operating within populations. However, variation could also be explained by small-scale differentiation combined with limited migration. Here, we report the existence of extreme variation in egg color in a population of Mexican Jays (Aphelocoma ultramarina) inhabiting a steep elevation and habitat gradient within a single mountain range, the Sierra del Carmen of Coahuila, Mexico. We quantified egg color of 143 eggs from 54 nests throughout the mountain range, using …


Biological Stoichiometry Of Plant Production: Metabolism, Scaling, And Ecological Response To Global Change, Andrew Kerkhoff, J.J. Elser, W.F. Fagan, B.J. Enquist Dec 2009

Biological Stoichiometry Of Plant Production: Metabolism, Scaling, And Ecological Response To Global Change, Andrew Kerkhoff, J.J. Elser, W.F. Fagan, B.J. Enquist

Andrew J Kerkhoff

No abstract provided.


Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg Dec 2009

Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg

Edgar Lehr

Species of frogs in the genus Telmatobius are traded and sold for human consumption in the Andes and in coastal cities of Peru and Bolivia. These frogs are harvested from wild populations. We report high prevalence of infection by the pathogenic fungus Batrachochytrium dendrobatidis in live frogs purchased at the main market in Cusco, Peru, from January 2008 to January 2010. We suggest that the transport of native anurans through the live frog trade could facilitate the spread of this fungus among Andean frogs. The tropical Andes are the most important biodiversity hotspot for amphibians. Because many neotropical taxa are …


A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer Dec 2009

A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer

Edgar Lehr

We describe a new species of the Hypsiboas pulchellus Group from the eastern Andes of central Peru (Region Pasco). Calls of both H. melanopleura and the new species are described. The new species is more similar to H. melanopleura and H. palaestes but differs in morphological characters and in coloration pattern. The new species and H. melanopleura are included in a molecular phylogenetic analysis of the H. pulchellus Group that shows them to be sister species and forming a second, independent, Andean clade within the group. New collecting sites for H. melanopleura are provided with the first record in the …


Darwinian Controversies: An Historiographical Recounting, David Depew Dec 2009

Darwinian Controversies: An Historiographical Recounting, David Depew

David J Depew

This essay reviews key controversies in the history of the Darwinian research tradition: the Wilberforce-Huxley debate in 1860, early twentieth-century debates about the heritability of acquired characteristics and the consistency of Mendelian genetics with natural selection; the 1925 Scopes trial about teaching evolution; tensions about race, culture, and eugenics at the 1959 centenary celebration Darwin’s Origin of Species; adaptationism and its critics in the Sociobiology debate of 1970s and, more recently, Evolutionary Psychology; and current disputes about Intelligent Design. These controversies, I argue, are etched into public memory because they occur at the emotionally charged boundaries between public-political, technical-scientific, and …


Two New Species Of Bryophryne (Anura: Strabomantidae) From High Elevations In Southern Peru (Region Of Cusco), Edgar Lehr, Alessandro Catenazzi Dec 2009

Two New Species Of Bryophryne (Anura: Strabomantidae) From High Elevations In Southern Peru (Region Of Cusco), Edgar Lehr, Alessandro Catenazzi

Edgar Lehr

We describe two new species of Bryophryne from the Region of Cusco, Provincia de La Convencio´n in southern Peru, increasing the number of currently known Bryophryne to eight. One of the new species is the second known species of Bryophryne that has a tympanic annulus and tympanic membrane. Males of this species have vocal slits, a vocal sac, and call from inside moss. It is readily distinguished from all its congeners by having a blackish-brown venter with yellow, orange, or pale pink blotches. This species is found at elevations of 3800–3850 m in the puna along the road from Vilcabamba …


Genetic Variation For Susceptibility To Storm-Induced Stem Breakage In Solidago Altissima: The Role Of Stem Height And Morphology, M. Wise, W. Abrahamson Dec 2009

Genetic Variation For Susceptibility To Storm-Induced Stem Breakage In Solidago Altissima: The Role Of Stem Height And Morphology, M. Wise, W. Abrahamson

Warren G. Abrahamson, II

While storms can have obvious ecological impacts on plants, plants’ potential to respond evolutionarily to selection for increased resistance to storm damage has received little study. We took advantage of a thunderstorm with strong wind and hail to examine genetic variation for resistance to stem breakage in the herbaceous perennial Solidago altissima. The storm broke the apex of nearly 10% of 1883 marked ramets in a common-garden plot containing 26 genets of S. altissima. Plant genets varied 20-fold in resistance to breakage. Stem height was strongly correlated with resistance to breakage, with taller stems being significantly more susceptible. A stem’s …


Differential Consumption Of Four Aphid Species By Four Lady Beetle Species, Christy Finlayson, Andrei Alyokhin, Serena Gross, Erin Porter Dec 2009

Differential Consumption Of Four Aphid Species By Four Lady Beetle Species, Christy Finlayson, Andrei Alyokhin, Serena Gross, Erin Porter

Andrei Alyokhin

The acceptability of four different aphid species Macrosiphum albifrons (Essig), Macrosiphum euphorbiae (Thomas), Macrosiphum pseudorosae Patch, and Myzus persicae (Sulzer) (Hemiptera: Aphididae), as prey for four lady beetle species, one native species Coccinella trifasciata L, and three non-native Coccinella septempunctata L, Harmonia axyridis Pallas, Propylea quatuordecimpunctata L (Coleoptera: Coccinellidae) were tested in the laboratory. The relative field abundance of adults of the same lady beetle species on host vegetation, Lupinus polyphyllus Lindley (Fabales: Fabaceae), Solanum tuberosum L (Solanales: Solanaceae), and Rosa multiflora Thunberg (Rosales: Rosaceae), both with and without aphids present was also observed. In the laboratory, H. axyridis generally …


Is Evolutionary Biology Infected With Invalid Teleological Reasoning? Invited Review Essay Of John Reiss, Retiring Darwin’S Watchmaker., David Depew Dec 2009

Is Evolutionary Biology Infected With Invalid Teleological Reasoning? Invited Review Essay Of John Reiss, Retiring Darwin’S Watchmaker., David Depew

David J Depew

No abstract provided.


Spatiotemporal Variation Of Fruit Digestible-Nutrient Production In Florida's Uplands, J. Layne, W. Abrahamson Dec 2009

Spatiotemporal Variation Of Fruit Digestible-Nutrient Production In Florida's Uplands, J. Layne, W. Abrahamson

Warren G. Abrahamson, II

We examined annual total digestible nutrient (TDN) production by fruits of eight species (Quercus chapmanii, Q. geminata, Q. inopina, Q. laevis, Q. myrtifolia, Carya floridana, Sabal etonia, Serenoa repens) that account for the major proportion of TDN production by fruits and seeds in Florida’s xeric upland associations (southern ridge sandhill, sand pine scrub, scrubby flatwoods). Mean annual fruit TDN of all species combined over a 27-year span in sandhill and scrub and 24 years in scrubby flatwoods was highest (45.4 kg/ha) in sandhill, intermediate in scrubby flatwoods (28.8 kg/ha), and lowest in scrub (14.2 kg/ha). Sandhill fruit TDN production was …


Synthetic Genome: Now That We’Re Creators, What Should We Create?, Frederick M. Cohan Dec 2009

Synthetic Genome: Now That We’Re Creators, What Should We Create?, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


The Ecology Of Speciation In Bacillus, Nora Connor, Johannes Sikorski, Alejandro P. Rooney, Sarah Kopac, Alexander F. Koeppel, Andrew Burger, Scott G. Cole, Elizabeth B. Perry, Danny Krizanc, Nicholas C. Field, Michele Slaton, Frederick M. Cohan Dec 2009

The Ecology Of Speciation In Bacillus, Nora Connor, Johannes Sikorski, Alejandro P. Rooney, Sarah Kopac, Alexander F. Koeppel, Andrew Burger, Scott G. Cole, Elizabeth B. Perry, Danny Krizanc, Nicholas C. Field, Michele Slaton, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken Dec 2009

Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken

Ryan Kerney

This study characterizes regulatory elements of collagen 2α1 (col2a1) in Xenopus that enable transgene expression in cartilage-forming chondrocytes. The reporters described in this study drive strong cartilage-specific gene expression, which will be a valuable tool for further investigations of Xenopus skeletal development. While endogenous col2a1 mRNA is expressed in many embryonic tissues, its expression becomes restricted to tadpole and adult chondrocytes. This chondrocyte-specific expression is recapitulated by col2a1 reporter constructs, which were tested through I-SceI meganuclease-mediated transgenesis. These constructs contain a portion of the Xenopus tropicalis col2a1 intron, which aligns to a cartilage-specific intronic enhancer that has been well characterized …


Ducking As The Means Of Resistance In "Candy-Cane" Stems Of Goldenrod: Straightened Stems Lose Their Edge, M. J. Wise, W. G. Abrahamson, J. A. Cole Dec 2009

Ducking As The Means Of Resistance In "Candy-Cane" Stems Of Goldenrod: Straightened Stems Lose Their Edge, M. J. Wise, W. G. Abrahamson, J. A. Cole

Warren G. Abrahamson, II

Herbivores are among the most pervasive selective forces acting on plants, and the number of plant chemicals that presumably evolved for defense against herbivory is immense. In contrast, biologists are only beginning to appreciate the important roles that architectural traits can play in antiherbivore defense. One putative architectural-resistance trait is the nodding stem apex of some goldenrods (Solidago ; Asteraceae). Individuals of S. altissima genets that undergo temporary nodding in the late spring (i.e., “candy-cane ramets) have been shown to be more resistant than individuals of erect-stemmed genets to certain apex-attacking” herbivores. We tested the hypothesis that the greater resistance …


Ontogeny Of Digestion Defenses In Daphnia: Implications For The Effectiveness Of Algal Defenses, William R. Demott Ph.D. Dec 2009

Ontogeny Of Digestion Defenses In Daphnia: Implications For The Effectiveness Of Algal Defenses, William R. Demott Ph.D.

William R. DeMott Ph.D.

No abstract provided.


Nutrition As A Facilitator Of Host-Race Formation: The Role Of Food Quality In The Shift Of A Stem-Boring Beetle To A Gall Host, C. P. Blair, R. V. Schlanger, S. E. Diamond, W. G. Abrahamson Dec 2009

Nutrition As A Facilitator Of Host-Race Formation: The Role Of Food Quality In The Shift Of A Stem-Boring Beetle To A Gall Host, C. P. Blair, R. V. Schlanger, S. E. Diamond, W. G. Abrahamson

Warren G. Abrahamson, II

1. The importance of host-race formation to herbivorous insect diversity depends on the likelihood that successful populations can be established on a new plant host. A previously unexplored ecological aid to success on a novel host is better nutritional quality. The role of nutrition was examined in the shift of the stem-boring beetle Mordellistena convicta to fly-induced galls on goldenrod and the establishment there of a genetically distinct gall host race. 2. First, larvae of the host race inhabiting stems of Solidago gigantea were transplanted into stems and galls of greenhouse-grown S. gigantea plants. At the end of larval development, …


Quite A Year And New Life For Panthera Tigris: The St. Petersburg Declaration And The Future Of Wild Tigers, Philip J. Nyhus, Lisa Ann Tekancic Dec 2009

Quite A Year And New Life For Panthera Tigris: The St. Petersburg Declaration And The Future Of Wild Tigers, Philip J. Nyhus, Lisa Ann Tekancic

Philip J. Nyhus

No abstract provided.


Polyphyly Of The Pikeminnows (Teleostei: Cyprinidae) Inferred Using Mitochondrial Dna Sequences, T. Heath Ogden Dec 2009

Polyphyly Of The Pikeminnows (Teleostei: Cyprinidae) Inferred Using Mitochondrial Dna Sequences, T. Heath Ogden

T. Heath Ogden

The phylogenetic relationships of the Colorado pikeminnow Ptychocheilus lucius, northern pikeminnow P. oregonensis, Sacramento pikeminnow P. grandis, Umpqua pikeminnow P. umpquae, and hardhead Mylopharodon conocephalus were examined by using molecular data to investigate monophyly of the genus Ptychocheilus. Phylogenies generated using DNA sequence data from the cytochrome b and 16S ribosomal DNA genes of the mitochondrial genome reveal that Ptychocheilus is a polyphyletic genus and suggest that the taxonomy of the group is in need of further revision. These data yield insights into the evolution of the pikeminnows and help place the significant evolutionary events in context with the geological …