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Taxonomic Status Of The Enigmatic Cryptotis Avia (Mammalia: Insectivora: Soricidae), With Comments On The Distribution Of The Colombian Small-Eared Shrew, Cryptotis Colombiana, Neal Woodman Oct 1996

Taxonomic Status Of The Enigmatic Cryptotis Avia (Mammalia: Insectivora: Soricidae), With Comments On The Distribution Of The Colombian Small-Eared Shrew, Cryptotis Colombiana, Neal Woodman

Neal Woodman

Cryptotis avia G. M. Allen 1823, from the Eastern Andean Cordillera of Colombia, is a small-eared shrew previously known from, at most, five specimens. Review of the holotype, consisting of an understuffed skin and a partial skull, and three potential topotypes indicates that they are refereable to Cryptotis thomasi Merriam, 1897, and C. avia should be considered ajunior synonym of that name. Cryptotis thomasi is restricted to highlands around Bogotá in the Eastern Cordillera. Another specimen previously referred to C. avia is the second known specimen of Cryptotis colombiana Woodman & Timm 1993. This second record expands the known distribution …


Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, Jason D. Nason, E. A. Stacy, J. L. Hamrick, S. P. Hubbell, R. B. Foster, R. Condit Aug 1996

Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, Jason D. Nason, E. A. Stacy, J. L. Hamrick, S. P. Hubbell, R. B. Foster, R. Condit

Jason D Nason

Studies of mating patterns of tropical trees, typically involving common species, have revealed that most species are outcrossed and that, in some cases, a significant reaction of outcross pollen moves long distances. We evaluated mating systems and effective pollen dispersal for three hermaphroditic insect-pollinated Neotropical tree species, Calophyllum longifolium, Spondias mombin and Turpinia occidentalis, all of which occurred at low adult densities at the study site. Mating patterns were estimated for each maternal tree within 84-ha populations of C. Longifoliuman d S. mombin in 1992 and 1993 and within a 50-ha population of T. occidentalis in 1993. Each population was …


Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, E. A. Stacy, J. L. Hamrick, J. D. Nason, S. P. Hubbell, R. B. Foster, R. Condit Jul 1996

Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, E. A. Stacy, J. L. Hamrick, J. D. Nason, S. P. Hubbell, R. B. Foster, R. Condit

John Nason

Studies of mating patterns of tropical trees, typically involving common species, have revealed that most species are outcrossed and that, in some cases, a significant fraction of outcross pollen moves long distances. We evaluated mating systems and effective pollen dispersal for three hermaphroditic, insect-pollinated Neotropical tree species, Calophyllum longifolium, Spondias mombin, and Turpinia occidentalis, all of which occurred at low adult densities at the study site. Mating patterns were estimated for each maternal tree within 84-ha populations of C. longifolium and S. mombin in 1992 and 1993 and within a 50-ha population of T. occidentalis in 1993. Each population was …


Bacillus Vallismortis Sp. Nov., A Close Relative Of Bacillus Subtilis, Isolated From Soil In Death Valley, California, Michael Roberts, Lawrence Nakamura, Frederick Cohan Jan 1996

Bacillus Vallismortis Sp. Nov., A Close Relative Of Bacillus Subtilis, Isolated From Soil In Death Valley, California, Michael Roberts, Lawrence Nakamura, Frederick Cohan

Frederick M. Cohan

No abstract provided.


Bird Aversive Properties Of Methyl Anthranilate, Yucca, Xanthoxylum, And Their Mixtures, Larry Clark, Bruce Bryant, Igor Mezine Jan 1996

Bird Aversive Properties Of Methyl Anthranilate, Yucca, Xanthoxylum, And Their Mixtures, Larry Clark, Bruce Bryant, Igor Mezine

Larry Clark

We tested the bird aversive properties of methyl anthranilate, yucca extracts, and Xanthoxylum spp. extracts in one- and two-bottle drinking assays that used European starlings (Sturnus vulgaris). In one- and two-bottle tests, methyl anthranilate proved to be the more potent stimulus in producing an avoidance response. Starlings avoided consuming Xanthoxylum and yucca only in the two-bottle tests. Previous studies showed that yucca was a good adjuvant in stabilizing lipophilic compounds in water. Starlings did not avoid binary mixtures of methyl anthranilate and yucca differently from what would be expected if they were only responding to the solution's methyl anthranilate content. …


Grazing Repellency Of Methyl Anthranilate To Snow Geese Is Enhanced By A Visual Cue, J. Russell Mason, Larry Clark Jan 1996

Grazing Repellency Of Methyl Anthranilate To Snow Geese Is Enhanced By A Visual Cue, J. Russell Mason, Larry Clark

Larry Clark

Methyl anthranilate (Rejex-It AG-36) is formulated as a commercial goose repellent. Frequent reapplications of this product are often necessary, and the cost/application is high ($300.00/ha). The present experiment tested the possibility that the repellency of methyl anthranilate might be enhanced by the addition of visual cues. Twelve 0.4 ha plots were assigned randomly to three treatment groups. Plots in the first group (n = 4) were sprayed with 10% Vapor Guard (an agrochemical adhesive). Plots in the second group (n = 4) were treated with a mixture of methyl anthranilate (3.4 kg/ha) and Vapor Guard. Plots in the third group …


Avoidance Of Cabbage Fields By Snow Geese, J. Russell Mason, Larry Clark Jan 1996

Avoidance Of Cabbage Fields By Snow Geese, J. Russell Mason, Larry Clark

Larry Clark

now Goose activity levels were significantly less in cabbage fields than in control fields. Although the data do not unambiguously address the issue of sulfur repellency, we believe that the activity difference is consistent with avoidance of the former and not preference for the latter. Sulfurous volatiles were readily apparent to us during our visits to cabbage fields throughout the study period. Similar odors were not detected in control fields. If sulfurous volatiles were important, then avoidance could reflect some characteristic of the cover crop (e.g., unpalatability acquired through the absorption and translocation of degra­ dation products) or it could …


Non-Mycorrhizal Uptake Of Amino Acids By Roots Of The Alpine Sedge Kobresia Myosuroides: Implications For The Alpine Nitrogen Cycle, Ted K. Raab, David A. Lipson, Russ K. Monson Jan 1996

Non-Mycorrhizal Uptake Of Amino Acids By Roots Of The Alpine Sedge Kobresia Myosuroides: Implications For The Alpine Nitrogen Cycle, Ted K. Raab, David A. Lipson, Russ K. Monson

Ted K. Raab

Non-mycorrhizal plants of the alpine sedge, Kobresia myosuroides , take up the amino acid glycine from nutrient solutions at greater rates than NO3- or NH4+. The amino acids glutamate and proline were also taken up at high rates. Total plant biomass was twice as high after 4 months of growth on glycine, compared to NH4NO3, with significant increases in both root and leaf biomass. By taking advantage of differences in the d13C signature of air in the growth chamber and the glycine used for growth, a two-member mixing model was used to estimate that a significant amount of the glycine …


Responses Of Moist And Dry Arctic Tundra To Trampling And Warmer Temperatures, Christopher Monz, G. A. Meier, R. C. Buckley, D. N. Cole, J. M. Welker, W. M. Loya Jan 1996

Responses Of Moist And Dry Arctic Tundra To Trampling And Warmer Temperatures, Christopher Monz, G. A. Meier, R. C. Buckley, D. N. Cole, J. M. Welker, W. M. Loya

Christopher Monz

No abstract provided.


Trees Of History In Systematics And Philology, Robert O’Hara Dec 1995

Trees Of History In Systematics And Philology, Robert O’Hara

Robert J. O’Hara

«The Natural System» is the name given to the underlying arrangement present in the diversity of life. Unlike a classification, which is made up of classes and members, a system or arrangement is an integrated whole made up of connected parts. In the pre-evolutionary period a variety of forms were proposed for the Natural System, including maps, circles, stars, and abstract multidimensional objects. The trees sketched by Darwin in the 1830s should probably be considered the first genuine evolutionary diagrams of the Natural System—the first genuine evolutionary trees. Darwin refined his image of the Natural System in the well-known evolutionary …


Lion-Tailed Macaques (Macaca Silenus) In A Disturbed Forest Fragment: Activity Patterns And Time Budget, Shaily Menon, Frank Poirier Dec 1995

Lion-Tailed Macaques (Macaca Silenus) In A Disturbed Forest Fragment: Activity Patterns And Time Budget, Shaily Menon, Frank Poirier

Shaily Menon

We describe the activity patterns and time budget of a feral group of lion-tailed macaques that were confined to a disturbed forest fragment of 65 ha and compare the results with those obtained for groups in protected forests. The degraded nature of the study site was reflected in low tree densities, low specific diversity, gaps in the girth distribution of trees, and frequent disturbance by humans. The study group of 43 subjects was twice as large as lion-tailed macaque groups in protected habitats. They spent the most time ranging (34.0%), followed by foraging (23.7%), feeding (17.9%), resting (16.0%), and other …


Natural Selection And Self-Organization: Dynamical Models As Clues To A New Evolutionary Synthesis, Bruce Weber, David Depew Dec 1995

Natural Selection And Self-Organization: Dynamical Models As Clues To A New Evolutionary Synthesis, Bruce Weber, David Depew

David J Depew

The Darwinian concept of natural selection was conceived within a set of Newtonianbackground assumptions about systems dynamics. Mendelian genetics at first did not sit well with the gradualist assumptions of the Darwinian theory. Eventually, however. Mendelism and Darwinism were fused by reformulating natural selection in statistical terms. This reflected a shift to a more probabilistic set of background assumptions based upon Boltzmannian systems dynamics. Recent developments in molecular genetics and paleontology have put pressure on Darwinism once again. Current work on self-organizing systems may provide a stimulus not only for increased problem solving within the Darwinian tradition, especially with respect …


Montandon Marsh: A Vegetation Description Of A Potentially Endangered Wetland, E. Hochman, W. Abrahamson, J. Clark Dec 1995

Montandon Marsh: A Vegetation Description Of A Potentially Endangered Wetland, E. Hochman, W. Abrahamson, J. Clark

Warren G. Abrahamson, II

No abstract provided.


Homology Among Nearly All Plasmids Infecting Three Bacillus Species, Piotr Zawadzki, Margaret A. Riley, Frederick M. Cohan Dec 1995

Homology Among Nearly All Plasmids Infecting Three Bacillus Species, Piotr Zawadzki, Margaret A. Riley, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


Assessment And Decision Making In Animals: A Mechanistic Model Underlying Behavioral Flexibility Can Prevent Ambiguity, Amos Bouskila, Daniel T. Blumstein Dec 1995

Assessment And Decision Making In Animals: A Mechanistic Model Underlying Behavioral Flexibility Can Prevent Ambiguity, Amos Bouskila, Daniel T. Blumstein

Amos Bouskila

Understanding how animals make decisions is a fundamental question in behavioral ecology which has cascading effects on how animals respond to environmental variation. An explicit model of the mechanisms of information processing and decision making can help prevent conflated definitions and ambiguous interpretations. Unambiguous definitions are crucial for clear communication between theoreticians and empiricists and for the rapid advancement of studies of decision making, Moreover, employing a clear model of underlying proximal processes will help bridge the gap between cognitive psychology and behavioral ecology and should aid scientific advancement. We present a simple model to guide studies of assessment and …


Trigeminal Repellents Do Not Promote Conditioned Odor Avoidance In European Starlings, Larry Clark Dec 1995

Trigeminal Repellents Do Not Promote Conditioned Odor Avoidance In European Starlings, Larry Clark

Larry Clark

Birds, and in particular European Starlings (Stumus vulgaris), avoid con­ sumption of fluid and food treated with the natural plant products, methyl anthranilate and o-aminoacetophenone. Avoidance is an unlearnedresponse most likely mediated via chem­ ically sensitive fibers of the trigeminal nerve. The trigeminal nerve codes for chemical irritation and pain. Starlings are not repelled by the odor of the compounds, nor is olfaction important in the avoidance response. Moreover, starlings fail to learn to avoid the odor of the repellents, even after direct oral contact with liquid repellent. While trigeminal irritants can be powerful repellents, the absence of associative learning …


Concaveation And Maintenance Of Maternal Behavior In A Burrower Bug (Sehirus Cinctus): A Comparative Perspective, Scott Kight Dec 1995

Concaveation And Maintenance Of Maternal Behavior In A Burrower Bug (Sehirus Cinctus): A Comparative Perspective, Scott Kight

Scott Kight

This study investigates 2 patterns of maternal behavior typical of mammals, using a heterop- teran insect as the study animal. Sehirus cinctus, a burrower bug (Heteroptera: Cydnidae), exhibits relatively well-developed maternal behavior that includes guarding eggs and provi- sioning offspring. Mothers remained maternally responsive to stimulus eggs for 24-48 hr following removal of their own eggs, but the response grew weaker with longer separation times. A proportion of nulliparous females also exhibited maternal responsiveness when presented with stimulus eggs. Males, however, never responded parentally to eggs. The results of this study highlight similarities in general female responsiveness to stimulus young …


Mapping The Space Of Time: Temporal Representation In The Historical Sciences, Robert J. O’Hara Dec 1995

Mapping The Space Of Time: Temporal Representation In The Historical Sciences, Robert J. O’Hara

Robert J. O’Hara

William Whewell (1794–1866), polymathic Victorian scientist, philosopher, historian, and educator, was one of the great neologists of the nineteenth century. Although Whewell’s name is little remembered today except by professional historians and philosophers of science, researchers in many scientific fields work each day in a world that Whewell named. “Miocene” and “Pliocene,” “uniformitarian” and “catastrophist,” “anode” and “cathode,” even the word “scientist” itself—all of these were Whewell coinages. Whewell is particularly important to students of the historical sciences for another word he coined, one that was unfortunately not as successful as many of his others because it is difficult to …