Life Sciences Commons^™

Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin

Ted K. Raab

A bright synchrotron light source operated by the Lawrence Berkeley National Laboratory served as an external source for infrared (IR) microscopy of plant root microcosms. Mid-IR light from synchrotrons is 2-3 orders of magnitude brighter than conventional sources, providing contrast based on the chemical information in the reflected signal at a spatial resolution near the diffraction-limit of 3-10 microns. In an experiment using plant root microcosms fitted with zinc selenide IR-transmissive windows (50 mm x 20 mm x 1 mm), we describe chemical differences and similarities within the root zone of mung bean (Vigna radiata L.), grown with or without …

On The Status Of The Serranid Fish Genus Epinephelus: Evidence For Paraphyly Based Upon 16s Rdna Sequence, Matthew T. Craig, Daniel Pondella Ii, Jens P.C Franckb, John C. Hafner

Daniel Pondella

Historically, attempts to elucidate evolutionary relationships among members of the genus Epinephelus (Teleostei: Serranidae), commonly known as groupers, have been hindered by the overwhelming number of species (98, sensu stricto), a pan global distribution, and the lack of morphological specializations traditionally used in ichthyological classification. To date, no comprehensive phylogenetic study, morphological or molecular, to evaluate the monophyly of this genus has been presented. In this study, previous hypotheses regarding the relationships among the American grouper species and the allied genera were evaluated by examination of mitochondrial DNA sequences of the 16S ribosomal DNA region. A 590-bp region of the …

The Use Of Red Mangrove As Nesting Substrate For Snail Kites In Florida, Victoria Dreitz, James Duberstein

Victoria Dreitz

No abstract provided.

Population Viability Of The Gulf Of Mexico Sturgeon In The Suwannee River, Florida, William Pine, Michael Allen, Victoria Dreitz

Victoria Dreitz

No abstract provided.

The Unusual Life History Of Alseis Blackiana: A Shade-Persistent Pioneer Tree?, Jason D. Nason, J. W. Dalling, K. Winter, S. P. Hubbell, D. A. Murawski, J. L. Hamrick

Jason D Nason

Classifications of tree species into regeneration guilds or functional groups are often based on a limited number of life history characteristics indicative of requirements for early establishment, with the assumption that these traits are correlated with growth requirements of larger individuals. We tested the validity of this assumption for Alseis blackiana, a common canopy tree in central Panama, by examining its seed germination, seedling growth, and sapling distribution, growth, and mortality. We found that the early life history of Alseis is characteristic of pioneer species: the seed germination rate was much higher in forest gaps than in the forest understory, …

Effects Of Elevated Co2 On The Response Of Phleum Pratense And Poa Pratensis To Aboveground Defoliation And Root-Feeding Nematodes, Brian J. Wilsey

Brian J. Wilsey

Because of the importance of herbivory in many herbaceous plant–dominated ecosystems, it will be important to determine whether interactions exist between herbivory and CO2 enrichment if we are to understand better how ecosystems will respond to global change. In an experiment with the C3 grasses Poa pratensis and Phleum pratense, plants were grown together under ambient (360 ppm) and elevated (650 ppm) CO2, with and without aboveground defoliation, and with or without additions of the root-feeding nematode Pratylenchus penetrans. The objective was to determine whether herbivory would interact with CO2 enrichment in determining biomass responses or whether these factors were …

Review Of Encyclopedia Of The Biosphere: Humans In The Worlds Ecosystems, John Stephen Brantley

Steve Brantley

No abstract provided.

New Species Of Bufo (Anura: Bufonidae) From Central Peru, Edgar Lehr, Elias Ponce, Gunther Kohler, Cesar Aguilar

Edgar Lehr

A new species of toad, Bufo chavin, is described from two localities (3010 and 3070 m) from the eastern Andean slopes of central Peru (Departamento de Huinuco, Provincia de Pachitea, Distrito de Chaglla)w here it occurs sympatrically with Bufos pinulosus. Bufo chavin is referred to the Bufo veraguensis group. The new species differs from all members of this group by having large, elevated, elongate glands on each forearm and tibia, two large, elevated, elongate glands on the outer dorsal margin of each foot and one small, elevated gland on the outer dorsal margin of each hand. Eggs are relatively large, …

Developmental Systems, Darwinian Evolution,And The Unity Of Science, Bruce Weber, David Depew

David J Depew

No abstract provided.

A New Species Of Phrynopus (Anura: Leptodactylidae) From The Eastern Andean Slopes Of Central Peru, Edgar Lehr

Edgar Lehr

A new species of leptodactylid frog, genus Phrynopus, is described from a Polylepis- forest of the eastern Andean slopes of central Peru (Departamento de Huánuco) between 3420 and 3430 m above sea level. The new species is assigned to the Phrynopus peruanus group and differs from all known species of the genus by having ventral surfaces of arms (except hands), legs (except feet), venter, chest and groin mainly red, and remaining dorsal, lateral and ventral surfaces of body with reticulated pattern and structure of slightly elevated brown to greenish blotches surrounded by cream to yellow lines. The new species occurs …

New Records For Amphibians And Reptiles From Departmentos Pasco And Ucayali, Peru, Edgar Lehr

Edgar Lehr

No abstract provided.

Zur Kenntnis Von Psomophis Genimaculatus (Boettger, 1885) In Paraguay Under Besonderer Berücksichtigung Des Defensiv-Verhaltens, Edgar Lehr, Thomas Ziegler, Jakob Unger

Edgar Lehr

Little is known about the terrestrial colubrid Psomophis Genimaculatus (BOETTGER, 1885), which inhabits the plains of East Bolivia, Southwest Brasil, West Paraguay and North Argentina; so, for this small snake, treated long time as synonym of the species joberti, only few records exist for the Paraguayan Gran Chaco. In this short note we provide additional data on its morphology, habitat and ecology in the Chaco of Paraguay. Further, we focus on an interesting defensive behaviour of that species, namely to sting with its tail tip, which is also discussed in the background of traditional records.

A New Species Of Osteocephalus With Bicoloured Iris From Pozuzo (Peru: Departamento De Pasco) (Amphibia: Anura: Hylidae), Edgar Lehr, Karl-Heinz Jungfer

Edgar Lehr

A new species of hylid frog, genus Osteocephalus is described from the eastern Andean slopes of central Peru (Pozuzo, Departamento Pasco) between 780 and 1000 m above sea level. It differs from all other species in the genus by the following combination of characters: small size, smooth dorsum in males, bicoloured iris lacking radiating dark lines, but finely reticulate ventrally, light, pale nuptial pads not keratinized, and subgular vocal sac. Females of the new species are unknown.

Genetic Biotechnology And Evolutionary Theory: Some Unsolicited Advice, David Depew

David J Depew

In his book The Biotech Century Jeremy Rifkin makes arguments about the dangers of market-driven genetic biotechnology in medical and agricultural contexts. Believing that Darwinism is too compromised by a competitive ethic to resist capitalist depredations of the “genetic commons,” and perhaps hoping to pick up anti-Darwinian allies, he turns for support to unorthodox non-Darwinian views of evolution. The Darwinian tradition, more closely examined, contains resources that might better serve his argument. The robust tradition associated with Theodosius Dobzhansky, Ernst Mayr, and others provides an alternative, scientifically sound basis for challenging the rhetoric of genetic reductionism.

Bacterial Species And Speciation, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

Demographic Parameters Of Golden Spotted Rock Bass Paralabrax Auroguttatus From The Northern Gulf Of California, Daniel Pondella Ii, Larry G. Allen, Jorge A. Rosales Casian, Tim E. Hovey

Daniel Pondella

The sex ratios, growth, and mortality of the golden spotted rock bass Paralabrax auroguttatus (Serranidae) were determined for populations from Islas Encantadas and Bahía de los Angeles in the Gulf of California. Specimens ranged from 137 to 479 mm standard length and from 135 to 3,100 g. Sagittal otoliths were used to determine age. A von Bertalanffy model of growth for both populations combined was estimated as Lt = 474.4·(1 − e −0.115( t + 2.093)), where Lt is fish length at age t. This model is comparable to those for other rock basses. The relationship between length and weight …

A New Species Of Marsupial Frog (Anura: Hylidae: Gastrotheca), Edgar Lehr, William E. Duellman, Cesar Aguilar

Edgar Lehr

A new species of Gastrotheca from the southern end of the Cordillera Azul in Peru seems to be most closely related to G. lateollota known only from the Cordillera Huancabamba in northern Peru. Both of these species and G. marsupiata, monticola and peruana produce tadpoles, whereas the other species of Gastrotheea in Peruvian Andes have direct development.

Bacillus Sonorensis Sp. Nov., A Close Relative Of Bacillus Licheniformis, Isolated From Soil In The Sonoran Desert, Arizona, M. M. Palmisano, L. K. Nakamura, K. E. Duncan, C. A. Istock, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

Tiger Restoration In Asia: Ecological Theory Vs. Sociological Reality, Ronald Tilson, Philip J. Nyhus, Neil Franklin

Philip J. Nyhus

No abstract provided.

Forest Dynamics In Flood Plain Forests In The Peruvian Amazon: Effects Of Disturbance And Implications For Management, Gustav Nebel, Lars Peter Kvist, Jerome K. Vanclay, Hector Vidaurre

Professor Jerome K Vanclay

Forest dynamics were studied from 1993 to 1997 for individuals > 10 cm DBH in nine 1 ha permanent sample plots. They were established in natural flood plain forests located on the lower Ucayali river in the Peruvian Amazon. After inventories of three plots in each of three forest types, a light and a heavy felling treatment were applied to each of the two plots, while a third plot was kept untreated. Average annual stem mortality and recruitment rates in the untreated plots were among the highest observed in neotropical rain forests: mortality 2.2-3.2% per year, recruitment 3.0-4.6% per year. Dead …

An Empirical Model Of Amino Acid Transformations In An Alpine Soil, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson

Ted K. Raab

Amino acids are potentially important nitrogen (N) sources for plants in many ecosystems. However, a quantitative understanding of organic N availability is lacking for most ecosystems. This study estimates seasonal amino acid fluxes in an alpine tundra soil using three independent data sets. In previous work in an alpine dry meadow ecosystem in the Front Range of the Colorado Rocky Mountains, we measured signifcant rates of amino acid production from soil peptides during the plant growing season. This suggested that proteolysis of native soil peptides could serve as a measure of amino acid availability to plants. Here we use a …

The Unusual Life History Of Alseis Blackiana: A Shade-Persistent Pioneer Tree?, J. W. Dalling, K. Winter, J. D. Nason, S. P. Hubbell, D. A. Murawski, J. L. Hamrick

John Nason

Body Size And Survivorship In Overwintering Populations Of Porcellio Laevis (Isopoda: Oniscidea), Scott Kight

Scott Kight

A Habitat Selection Game Of Interactions Between Rodents And Their Predators, Amos Bouskila

Amos Bouskila

No abstract provided.