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Full-Text Articles in Life Sciences
Low-Severity Fire Increases Tree Defense Against Bark Beetle Attacks, Sharon Metzger Hood, Anna Sala, Emily K. Heyerdahl, Marion Boutin
Low-Severity Fire Increases Tree Defense Against Bark Beetle Attacks, Sharon Metzger Hood, Anna Sala, Emily K. Heyerdahl, Marion Boutin
Biological Sciences Faculty Publications
Induced defense is a common plant strategy in response to herbivory. Although abiotic damage, such as physical wounding, pruning, and heating, can induce plant defense, the effect of such damage by large-scale abiotic disturbances on induced defenses has not been explored and could have important consequences for plant survival facing future biotic disturbances. Historically, low-severity wildfire was a widespread, frequent abiotic disturbance in many temperate coniferous forests. Native Dendroctonus and Ips bark beetles are also a common biotic disturbance agent in these forest types and can influence tree mortality patterns after wildfire. Therefore, species living in these disturbance-prone environments with …
White-Tailed Deer Are A Biotic Filter During Community Assembly, Reducing Species And Phylogenetic Diversity, Danielle R. Begley-Miller, Andrew L. Hipp, Bethany H. Brown, Marlene Hahn, Thomas P. Rooney
White-Tailed Deer Are A Biotic Filter During Community Assembly, Reducing Species And Phylogenetic Diversity, Danielle R. Begley-Miller, Andrew L. Hipp, Bethany H. Brown, Marlene Hahn, Thomas P. Rooney
Biological Sciences Faculty Publications
Community assembly entails a filtering process, where species found in a local community are those that can pass through environmental (abiotic) and biotic filters and successfully compete. Previous research has demonstrated the ability of white-tailed deer (Odocoileus virginianus) to reduce species diversity and favour browse-tolerant plant communities. In this study, we expand on our previous work by investigating deer as a possible biotic filter altering local plant community assembly. We used replicated 23-year-old deer exclosures to experimentally assess the effects of deer on species diversity (H′), richness (SR), phylogenetic community structure and phylogenetic diversity in paired …
Effects Of Predation Upon The Long-Spined Sea Urchin Diadema Antillarum By The Spotted Spiny Lobster Panulirus Guttatus, Meredith D. Kintzing, Mark J. Butler Iv
Effects Of Predation Upon The Long-Spined Sea Urchin Diadema Antillarum By The Spotted Spiny Lobster Panulirus Guttatus, Meredith D. Kintzing, Mark J. Butler Iv
Biological Sciences Faculty Publications
Sea urchins, important herbivores in marine ecosystems, are strongly impacted by both the direct and indirect effects of predation, and the long-spined sea urchin Diadema antillarum is no exception. Once abundant on Caribbean coral reefs, D. antillarum populations were decimated by disease in the early 1980s, and only where their natural predators have been over-fished has D. antillarum recovery been observed. Spiny lobsters (Palinuridae) are predators of sea urchins, and although there are several species of spiny lobster in the Caribbean, only the spotted spiny lobster Panulirus guttatus is restricted to coral reefs where D. antillarum dwells. We investigated the …
Direct And Legacy Effects Of Long-Term Elevated Co2 On Fine Root Growth And Plant-Insect Interactions, Peter Stiling, Daniel Moon, Anthony Rossi, Rebecca Forkner, Bruce A. Hungate, Frank P. Day, Rachel E. Schroeder, Bert Drake
Direct And Legacy Effects Of Long-Term Elevated Co2 On Fine Root Growth And Plant-Insect Interactions, Peter Stiling, Daniel Moon, Anthony Rossi, Rebecca Forkner, Bruce A. Hungate, Frank P. Day, Rachel E. Schroeder, Bert Drake
Biological Sciences Faculty Publications
Increasing atmospheric CO2 concentrations alter leaf physiology, with effects that cascade to communities and ecosystems. Yet, responses over cycles of disturbance and recovery are not well known, because most experiments span limited ecological time. We examined the effects of CO2 on root growth, herbivory and arthropod biodiversity in a woodland from 1996 to 2006, and the legacy of CO2 enrichment on these processes during the year after the CO2 treatment ceased. We used minirhizotrons to study root growth, leaf censuses to study herbivory and pitfall traps to determine the effects of elevated CO2 on arthropod …
The Likelihood Of Extinction Of Iconic And Dominant Herbivores And Detritivores Of Coral Reefs: The Parrotfishes And Surgeonfishes, Mia T. Comeros-Raynal, John H. Choat, Beth A. Polidoro, Kendall D. Clements, Rene Abesamis, Matthew T. Craig, Muhammad E. Lazuardi, Jennifer Mcilwain, Andreas Muljadi, Robert F. Myers, Cleto L. Nanola Jr., Shinta Pardede, Luiz A. Rocha, Barry Russell, Jonnell C. Sanciangco, Brian Stockwell, Heather Harwell, Kent E. Carpenter
The Likelihood Of Extinction Of Iconic And Dominant Herbivores And Detritivores Of Coral Reefs: The Parrotfishes And Surgeonfishes, Mia T. Comeros-Raynal, John H. Choat, Beth A. Polidoro, Kendall D. Clements, Rene Abesamis, Matthew T. Craig, Muhammad E. Lazuardi, Jennifer Mcilwain, Andreas Muljadi, Robert F. Myers, Cleto L. Nanola Jr., Shinta Pardede, Luiz A. Rocha, Barry Russell, Jonnell C. Sanciangco, Brian Stockwell, Heather Harwell, Kent E. Carpenter
Biological Sciences Faculty Publications
Parrotfishes and surgeonfishes perform important functional roles in the dynamics of coral reef systems. This is a consequence of their varied feeding behaviors ranging from targeted consumption of living plant material (primarily surgeonfishes) to feeding on detrital aggregates that are either scraped from the reef surface or excavated from the deeper reef substratum (primarily parrotfishes). Increased fishing pressure and widespread habitat destruction have led to population declines for several species of these two groups. Species-specific data on global distribution, population status, life history characteristics, and major threats were compiled for each of the 179 known species of parrotfishes and surgeonfishes …
Human Activity Mediates A Trophic Cascade Caused By Wolves, Mark Hebblewhite, Clifford A. White, Clifford G. Nietvelt, John A. Mckenzie, Tomas E. Hurd, John M. Fryxell, Suzanne E. Bayley, Paul C. Paquet
Human Activity Mediates A Trophic Cascade Caused By Wolves, Mark Hebblewhite, Clifford A. White, Clifford G. Nietvelt, John A. Mckenzie, Tomas E. Hurd, John M. Fryxell, Suzanne E. Bayley, Paul C. Paquet
Biological Sciences Faculty Publications
Experimental evidence of trophic cascades initiated by large vertebrate predators is rare in terrestrial ecosystems. A serendipitous natural experiment provided an opportunity to test the trophic cascade hypothesis for wolves (Canis lupus) in Banff National Park, Canada. The first wolf pack recolonized the Bow Valley of Banff National Park in 1986. High human activity partially excluded wolves from one area of the Bow Valley (low-wolf area), whereas wolves made full use of an adjacent area (high-wolf area). We investigated the effects of differential wolf predation between these two areas on elk (Cervus elaphus) population density, adult …
Leafcutting And Diet Selection: Relative Influence Of Leaf Chemistry And Physical Features, Jerome J. Howard
Leafcutting And Diet Selection: Relative Influence Of Leaf Chemistry And Physical Features, Jerome J. Howard
Biological Sciences Faculty Publications
The effects of leaf toughness, trichome characteristics, nutrient and water availability, and secondary chemistry on diet selection by the leafcutting ant Atta cephalotes were determined using individuals of 49 woody plant species from a tropical deciduous forest in Costa Rica. The palatability of plants was measured by presenting whole leaves to leafcutting ant foragers on trails and counting the number of pieces cut from leaves. The effectiveness of physical barriers to leaf cutting was evaluated by measuring the speed with which ants were able to cut leaves of varying toughness, trichome densities, and trichome lengths. Plant secondary chemistry was highly …
Leafcutting Ant Diet Selection: The Role Of Nutrients, Water, And Secondary Chemistry, Jerome J. Howard
Leafcutting Ant Diet Selection: The Role Of Nutrients, Water, And Secondary Chemistry, Jerome J. Howard
Biological Sciences Faculty Publications
The relationship of plant secondary chemistry, water content, and nutrient content to the palatability of leaves to the leafcutting ant Atta cephalotes was determined in a study of individuals from 50 woody plant species in tropical dry forest of Costa Rica. The study took place during the yearly period of maximum leaf harvest, in the early rainy season. The palatability of plants was determined by presenting leaf disks to ants on active foraging trails of three ant colonies. The distribution of several classes of polar secondary compounds in leaf samples was determined using chemical spot tests, and that of ant- …
Chemical Leaf Repellency To An Attine Ant: Seasonal Distribution Among Potential Host Plant Species, Jerome J. Howard
Chemical Leaf Repellency To An Attine Ant: Seasonal Distribution Among Potential Host Plant Species, Jerome J. Howard
Biological Sciences Faculty Publications
The chemical repellency of leaves to the leaf-cutting, fungus-growing ant Atta cephalotes was surveyed for 42 plant species randomly selected from the dry forest of Santa Rosa National Park, Guanacaste, Costa Rica. The sample represents about one-sixth of the potential host plant species available to the ants in the secondary, semideciduous forest at Santa Rosa. Repellencies of leaf extracts were measured by bioassay. A laboratory colony of A. cephalotes collected from Santa Rosa was used. Three-quarters of the species exhibited significantly repellent nonpolar (lipid-soluble) extractables (e.g., terpenoids, steroids, and waxes), and half of the species exhibited repellent polar extractables (e.g., …