Biology Commons^™

The Actin Cytoskeletal Network Plays A Role In Yeast Prion Transmission And Contributes To Prion Stability, Jane E. Dorweiler, Mitchell J. Oddo, Douglas R. Lyke, Jacob A. Reilly, Brett T. Wisniewski, Emily E. Davis, Abigail M. Kuborn, Stephen J. Merrill, Anita L. Manogaran

Biological Sciences Faculty Research and Publications

Chaperone networks are required for the shearing and generation of transmissible propagons from pre‐existing prion aggregates. However, other cellular networks needed for maintaining yeast prions are largely uncharacterized. Here, we establish a novel role for actin networks in prion maintenance. The [PIN ⁺] prion, also known as [RNQ ⁺], exists as stable variants dependent upon the chaperone machinery for the transmission of propagons to daughter cells during cell division and cytoplasmic transfer. Loss of the Hsp104 molecular chaperone leads to the growth of prion particles until they are too large to be transmitted. Here, we isolated …

The Structure And Symmetry Of The Radial Spoke Protein Complex In Chlamydomonas Flagella, Emiliya Poghosyan, Ioan Iacovache, Lenka Faltova, Alexander Leitner, Pinfen Yang, Dennis R. Diener, Ruedi Aebersold, Benoit Zuber, Takashi Ishikawa

Biological Sciences Faculty Research and Publications

The radial spoke is a key element in a transducer apparatus controlling the motility of eukaryotic cilia. The transduction biomechanics is a long-standing question in cilia biology. The radial spoke has three regions – a spoke head, a bifurcated neck and a stalk. Although the neck and the stalk are asymmetric, twofold symmetry of the head has remained controversial. In this work we used single particle cryo-electron microscopy (cryo-EM) analysis to generate a 3D structure of the whole radial spoke at unprecedented resolution. We show the head region at 15 Å (1.5 nm) resolution and confirm twofold symmetry. Using distance …

Multiple Cold Tolerance Trait Phenotyping Reveals Shared Quantitative Trait Loci In Oryza Sativa, Naoki Shimoyama, Melineeh Johnson, André Beaumont, Michael Schläppi

Biological Sciences Faculty Research and Publications

Background

Developing chilling tolerant accessions of domesticated Asian rice is a potential source of significant crop improvement. The uniquely chilling sensitive nature of the tropically originating Oryza sativa make it the most important cereal crop that can gain significantly from improved tolerance to low temperatures. However, mechanisms underlying this complex trait are not fully understood. Oryza sativa has two subspecies with different levels of chilling tolerance, JAPONICA and INDICA, providing an ideal tool to investigate mechanistic differences in the chilling stress tolerance responses within this important crop species.

Results

The Rice Diversity Panel 1 (RDP1) was used to investigate …

Individual Learning Phenotypes Drive Collective Behavior, Chelsea N. Cook, Natalie J. Lemanski, Thiago Mosqueiro, Cahit Ozturk, Jürgen Gadau, Noa Pinter-Wollman, Brian H. Smith

Biological Sciences Faculty Research and Publications

Individual differences in learning can influence how animals respond to and communicate about their environment, which may nonlinearly shape how a social group accomplishes a collective task. There are few empirical examples of how differences in collective dynamics emerge from variation among individuals in cognition. Here, we use a naturally variable and heritable learning behavior called latent inhibition (LI) to show that interactions among individuals that differ in this cognitive ability drive collective foraging behavior in honey bee colonies. We artificially selected two distinct phenotypes: high-LI bees that ignore previously familiar stimuli in favor of novel ones and low-LI bees …

Human Health, Interagency Coordination, And The Need For Biodiversity Data, Jennifer M. Zaspel, Julie M. Allen, Christopher D. Tyrrell, Nathan P. Lemoine, Luke M. Jacobus, Crystal Klem, Jillian Goodwin, John M. Bates

Biological Sciences Faculty Research and Publications

No abstract provided.

Potent Inhibition Of Mandelate Racemase By Boronic Acids: Boron As A Mimic Of A Carbon Acid Center, Amar Nath Sharma, Lia Grandinetti, Erin R. Johnson, Martin St. Maurice, Stephen L. Bearne

Biological Sciences Faculty Research and Publications

Boronic acids have been successfully employed as inhibitors of hydrolytic enzymes. Typically, an enzymatic nucleophile catalyzing hydrolysis adds to the electrophilic boron atom forming a tetrahedral species that mimics the intermediate(s)/transition state(s) for the hydrolysis reaction. We show that para-substituted phenylboronic acids (PBAs) are potent competitive inhibitors of mandelate racemase (MR), an enzyme that catalyzes a 1,1-proton transfer rather than a hydrolysis reaction. The K_i value for PBA was 1.8 ± 0.1 μM, and p-Cl-PBA exhibited the most potent inhibition (K_i = 81 ± 4 nM), exceeding the binding affinity of the substrate by ∼4 …

First Report Of Sex Chromosomes In Night Lizards (Scincoidea: Xantusiidae), Stuart V. Nielsen, Brendan John Pinto, IráN Andira Guzmán-Méndez, Tony Gamble

Biological Sciences Faculty Research and Publications

Squamate reptiles (lizards, snakes, and amphibians) are an outstanding group for studying sex chromosome evolution—they are old, speciose, geographically widespread, and exhibit myriad sex-determining modes. Yet, the vast majority of squamate species lack heteromorphic sex chromosomes. Cataloging the sex chromosome systems of species lacking easily identifiable, heteromorphic sex chromosomes, therefore, is essential before we are to fully understand the evolution of vertebrate sex chromosomes. Here, we use restriction site-associated DNA sequencing (RADseq) to classify the sex chromosome system of the granite night lizard, Xantusia henshawi. RADseq is an effective alternative to traditional cytogenetic methods for determining a species’ sex …

Parallel Evolution Of Tobramycin Resistance Across Species And Environments, Michelle R. Scribner, Alfonso Santos-Lopez, Christopher Marshall, Christopher Deitrick, Vaughn S. Cooper

Biological Sciences Faculty Research and Publications

Different species exposed to a common stress may adapt by mutations in shared pathways or in unique systems, depending on how past environments have molded their genomes. Understanding how diverse bacterial pathogens evolve in response to an antimicrobial treatment is a pressing example of this problem, where discovery of molecular parallelism could lead to clinically useful predictions. Evolution experiments with pathogens in environments containing antibiotics, combined with periodic whole-population genome sequencing, can be used to identify many contending routes to antimicrobial resistance. We separately propagated two clinically relevant Gram-negative pathogens, Pseudomonas aeruginosa and Acinetobacter baumannii, in increasing concentrations of …

Allometric Scaling Laws Linking Biomass And Rooting Depth Vary Across Ontogeny And Functional Groups In Tropical Dry Forest Lianas And Trees, Chris M. Smith-Martin, Xiangtao Xu, David Medvigy, Stefan A. Schnitzer, Jennifer S. Powers

Biological Sciences Faculty Research and Publications

• There are two theories about how allocation of metabolic products occurs. The allometric biomass partitioning theory (APT) suggests that all plants follow common allometric scaling rules. The optimal partitioning theory (OPT) predicts that plants allocate more biomass to the organ capturing the most limiting resource.
• Whole-plant harvests of mature and juvenile tropical deciduous trees, evergreen trees, and lianas and model simulations were used to address the following knowledge gaps: (1) Do mature lianas comply with the APT scaling laws or do they invest less biomass in stems compared to trees? (2) Do juveniles follow the same allocation patterns as mature …

Lianas Reduce Biomass Accumulation In Early Successional Tropical Forests, Sergio Estrada Villegas, Jefferson S. Hall, Michiel Van Breugel, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

Early successional tropical forests could mitigate climate change via rapid accumulation of atmospheric carbon. However, liana (woody vine) abundance and biomass has been increasing in many tropical forests over the past decades, which may slow the speed at which secondary forests accumulate biomass. Lianas decrease biomass accumulation in tropical forests, and may have a particularly strong effect on young forests by stalling tree growth. As forests mature, trees may outgrow or shed lianas, thus escaping some of the negative effects of lianas. Alternatively, lianas may have the strongest effect in older successional forests if the effect of lianas is commensurate …

Macroborer Presence On Corals Increases With Nutrient Input And Promotes Parrotfish Bioerosion, Mallory M. Rice, Rebecca L. Maher, Adrienne M.S. Correa, Holly V. Moeller, Nathan P. Lemoine, Andrew A. Shantz, Deron E. Burkepile, Nyssa J. Silbiger

Biological Sciences Faculty Research and Publications

Bioerosion by reef-dwelling organisms influences net carbonate budgets on reefs worldwide. External bioeroders, such as parrotfish and sea urchins, and internal bioeroders, including sponges and lithophagid bivalves, are major contributors to bioerosion on reefs. Despite their importance, few studies have examined how environmental (e.g., nutrients) or biological drivers (e.g., the actions of other bioeroders) may influence bioeroder dynamics on reefs. For example, internal bioeroders could promote external bioerosion by weakening the coral skeletal matrix. Our study investigated: ( 1) whether nutrient supply influences the dynamics between internal and external bioeroders and ( 2) how the presence of a boring bivalve, …

Local Species Diversity, Β-Diversity And Climate Influence The Regional Stability Of Bird Biomass Across North America, Christopher P. Catano, Trevor S. Fristoe, Joseph A. Lamanna, Jonathan A. Myers

Biological Sciences Faculty Research and Publications

Biodiversity often stabilizes aggregate ecosystem properties (e.g. biomass) at small spatial scales. However, the importance of species diversity within communities and variation in species composition among communities (β-diversity) for stability at larger scales remains unclear. Using a continental-scale analysis of 1657 North American breeding-bird communities spanning 20-years and 35 ecoregions, we show local species diversity and β-diversity influence two components of regional stability: local stability (stability of bird biomass within sites) and spatial asynchrony (asynchronous fluctuations in biomass among sites). We found spatial asynchrony explained three times more variation in regional stability of bird biomass than did local stability. This …

Optimizing Phylogenomics With Rapidly Evolving Long Exons: Comparison With Anchored Hybrid Enrichment And Ultraconserved Elements, Benjamin R. Karin, Tony Gamble, Todd R. Jackman

Biological Sciences Faculty Research and Publications

Marker selection has emerged as an important component of phylogenomic study design due to rising concerns of the effects of gene tree estimation error, model misspecification, and data-type differences. Researchers must balance various trade-offs associated with locus length and evolutionary rate among other factors. The most commonly used reduced representation data sets for phylogenomics are ultraconserved elements (UCEs) and Anchored Hybrid Enrichment (AHE). Here, we introduce Rapidly Evolving Long Exon Capture (RELEC), a new set of loci that targets single exons that are both rapidly evolving (evolutionary rate faster than RAG1) and relatively long in length (>1,500 bp), …

Experimental Psychology Meets Behavioral Ecology: What Laboratory Studies Of Learning Polymorphisms Mean For Learning Under Natural Conditions, And Vice Versa, Brian H. Smith, Chelsea N. Cook

Biological Sciences Faculty Research and Publications

Behavior genetics, and specifically the study of learning and memory, has benefitted immensely from the development of powerful forward- and reverse-genetic methods for investigating the relationships between genes and behavior. Application of these methods in controlled laboratory settings has led to insights into gene–behavior relationships. In this perspective article, we argue that the field is now poised to make significant inroads into understanding the adaptive value of heritable variation in behavior in natural populations. Studies of natural variation with several species, in particular, are now in a position to complement laboratory studies of mechanisms, and sometimes this work can lead …

The Development Of Cephalic Armor In The Tokay Gecko (Squamata: Gekkonidae: Gekko Gecko), Rebecca J. Laver, Cristian H. Morales, Matthew P. Heinicke, Tony Gamble, Kristin Longoria, Aaron M. Bauer, Juan D. Daza

Biological Sciences Faculty Research and Publications

Armored skin resulting from the presence of bony dermal structures, osteoderms, is an exceptional phenotype in gekkotans (geckos and flap-footed lizards) only known to occur in three genera: Geckolepis, Gekko, and Tarentola. The Tokay gecko (Gekko gecko LINNAEUS 1758) is among the best-studied geckos due to its large size and wide range of occurrence, and although cranial dermal bone development has previously been investigated, details of osteoderm development along a size gradient remain less well-known. Likewise, a comparative survey of additional species within the broader Gekko clade to determine the uniqueness of this trait has not …

Bromocriptine Improves Glucose Tolerance Independent Of Circadian Timing, Prolactin, Or The Melanocortin-4 Receptor, Sarah N. Framnes-Deboer, Ellen Bakke, Suma Yalamanchili, Hannah Peterson, Darleen A. Sandoval, Randy J. Seeley, Deanna M. Arble

Biological Sciences Faculty Research and Publications

Bromocriptine, a dopamine D2 receptor agonist originally used for the treatment of hyperprolactinemia, is largely successful in reducing hyperglycemia and improving glucose tolerance in type 2 diabetics. However, the mechanism behind bromocriptine’s effect on glucose intolerance is unclear. Here, we tested three hypotheses, that bromocriptine may exert its effects on glucose metabolism by 1) decreasing prolactin secretion, 2) indirectly increasing activity of key melanocortin receptors in the central nervous system, or 3) improving/restoring circadian rhythms. Using a diet-induced obese (DIO) mouse model, we established that a 2-wk treatment of bromocriptine is robustly effective at improving glucose tolerance. …

Edaphic Factors And Initial Conditions Influence Successional Trajectories Of Early Regenerating Tropical Dry Forests, Sergio Estrada Villegas, Mario Bailón, Jefferson S. Hall, Stefan A. Schnitzer, Benjamin L. Turner, Trevor Caughlin, Michiel Van Breugel

Biological Sciences Faculty Research and Publications

1. Edaphic factors and initial conditions can regulate the speed of forest succession. Edaphic factors, which include soil chemistry and topography, determine soil resource availability and can filter species as forests mature. Initial plant cover early in succession can determine the rates at which secondary forests change in structure, richness, biomass and composition over time. While some of the effects of edaphic factors and initial conditions on forest succession have been studied, how they simultaneously modify young regenerating tropical forest has rarely been examined.
2. We surveyed 22 young forests plots in Panama for 7 years (11, 6 and 3‐year‐old stands when …

Distinct Patterns Of Pigment Development Underlie Convergent Hyperpigmentation Between Nocturnal And Diurnal Geckos (Squamata: Gekkota), Aaron H. Griffing, Tony Gamble, Aaron M. Bauer

Biological Sciences Faculty Research and Publications

Background

Evolutionary transitions in temporal niche necessitates specialized morphology, physiology, and behaviors. Diurnal, heliothermic squamates (lizards and snakes) that bask require protection from ultraviolet radiation (UV) that can damage internal organs such as the brain, viscera, and gonads. Many smaller squamates have accomplished this protection by hyperpigmentation of the peritoneum and subcutaneous dorsum. Typically, nocturnal species do not require these protections from ultraviolet light. However, some nocturnal species that exhibit extreme crypsis may be exposed to sunlight and UV and require some means of mediating that damage. One such species is Gekko (Ptychozoon) kuhli, a nocturnal, arboreal …

Defects In Mating Behavior And Tail Morphology Are The Primary Cause Of Sterility In Caenorhabditis Elegans Males At High Temperature, Emily M. Nett, Nicholas B. Sepulveda, Lisa N. Petrella

Biological Sciences Faculty Research and Publications

Reproduction is a fundamental imperative of all forms of life. For all the advantages sexual reproduction confers, it has a deeply conserved flaw: it is temperature sensitive. As temperatures rise, fertility decreases. Across species, male fertility is particularly sensitive to elevated temperature. Previously, we have shown in the model nematode Caenorhabditis elegans that all males are fertile at 20°C, but almost all males have lost fertility at 27°C. Male fertility is dependent on the production of functional sperm, successful mating and transfer of sperm, and successful fertilization post-mating. To determine how male fertility is impacted by elevated temperature, we analyzed …

Transcriptomic Data Support A Nocturnal Bottleneck In The Ancestor Of Gecko Lizards, Brendan J. Pinto, Stuart V. Nielsen, Tony Gamble

Biological Sciences Faculty Research and Publications

Gecko lizards are a species-rich clade of primarily-nocturnal squamate reptiles. In geckos, adaptations to nocturnality have dramatically reshaped the eye. Perhaps the most notable change is the loss of rod cells in the retina and subsequent “transmutation” of cones into a rod-like morphology and physiology. While many studies have noted the absence of some rod-specific genes, such as the visual pigment Rhodopsin (RH1), these studies have focused on just a handful of species that are nested deep in the gecko phylogeny. Thus, it is not clear whether these changes arose through convergence, are homologous and ubiquitous across geckos, or restricted …

Hypoxia-Inducible Gene Domain 1 Proteins In Yeast Mitochondria Protect Against Proton Leak Through Complex Iv, Ngoc H. Hoang, Vera Strogolova, Jaramys J. Mosley, Rosemary A. Stuart, Jonathan Hosler

Biological Sciences Faculty Research and Publications

Hypoxia-inducible gene domain 1 (HIGD1) proteins are small integral membrane proteins, conserved from bacteria to humans, that associate with oxidative phosphorylation supercomplexes. Using yeast as a model organism, we have shown previously that its two HIGD1 proteins, Rcf1 and Rcf2, are required for the generation and maintenance of a normal membrane potential (ΔΨ) across the inner mitochondrial membrane (IMM). We postulated that the lower ΔΨ observed in the absence of the HIGD1 proteins may be due to decreased proton pumping by complex IV (CIV) or enhanced leak of protons across the IMM. Here we measured the ΔΨ generated by complex …

Embryonic Development Of A Parthenogenetic Vertebrate, The Mourning Gecko (Lepidodactylus Lugubris), Aaron H. Griffing, Thomas J. Sanger, Juan D. Daza, Stuart V. Nielsen, Brendan J. Pinto, Edward L. Stanley, Tony Gamble

Biological Sciences Faculty Research and Publications

Background

One goal of evolutionary developmental biology is to understand the role of development in the origin of phenotypic novelty and convergent evolution. Geckos are an ideal system to study this topic, as they are species‐rich and exhibit a suite of diverse morphologies—many of which have independently evolved multiple times within geckos.

Results

We characterized and discretized the embryonic development of Lepidodactylus lugubris—an all‐female, parthenogenetic gecko species. We also used soft‐tissue μCT to characterize the development of the brain and central nervous system, which is difficult to visualize using traditional microscopy techniques. Additionally, we sequenced and assembled a de …

Do Lianas Shape Ant Communities In An Early Successional Tropical Forest?, Benjamin J. Adams, Evan M. Gora, Michiel Van Breugel, Sergio Estrada-Villegas, Stefan A. Schnitzer, Jefferson S. Hall, Stephen P. Yanoviak

Biological Sciences Faculty Research and Publications

Almost half of lowland tropical forests are at various stages of regeneration following deforestation or fragmentation. Changes in tree communities along successional gradients have predictable bottom‐up effects on consumers. Liana (woody vine) assemblages also change with succession, but their effects on animal succession remain unexplored. Here we used a large‐scale liana removal experiment across a forest successional chronosequence (7–31 years) to determine the importance of lianas to ant community structure. We conducted 1,088 surveys of ants foraging on and living in trees using tree trunk baiting and hand‐collecting techniques at 34 paired forest plots, half of which had all lianas …

C. Elegans Synmuv B Proteins Regulate Spatial And Temporal Chromatin Compaction During Development, Meghan Elizabeth Costello, Lisa N. Petrella

Biological Sciences Faculty Research and Publications

Tissue-specific establishment of repressive chromatin through creation of compact chromatin domains during development is necessary to ensure proper gene expression and cell fate. Caenorhabditis elegans synMuv B proteins are important for the soma/germline fate decision and mutants demonstrate ectopic germline gene expression in somatic tissue, especially at high temperature. We show that C. elegans synMuv B proteins regulate developmental chromatin compaction and that the timing of chromatin compaction is temperature sensitive in both wild type and synMuv B mutants. Chromatin compaction in mutants is delayed into developmental time periods when zygotic gene expression is upregulated and demonstrates an anterior-to-posterior pattern. …

Escaping The Evolutionary Trap? Sex Chromosome Turnover In Basilisks And Related Lizards (Corytophanidae: Squamata), Stuart V. Nielsen, Irán Andira Guzmán-Méndez, Tony Gamble, Madison Blumer, Brendan J. Pinto, Lukáš Kratochvíl, Michail Rovatsos

Biological Sciences Faculty Research and Publications

Most pleurodont lizard families (anoles, iguanas and their relatives), with the exception of the basilisks and casquehead lizards (family Corytophanidae), share homologous XX/XY sex chromosomes, syntenic with chicken chromosome 15. Here, we used a suite of methods (i.e. RADseq, RNAseq and qPCR) to identify corytophanid sex chromosomes for the first time. We reveal that all examined corytophanid species have partially degenerated XX/XY sex chromosomes, syntenic with chicken chromosome 17. Transcriptomic analyses showed that the expression of X-linked genes in the corytophanid, Basiliscus vittatus, is not balanced between the sexes, which is rather exceptional under male heterogamety, and unlike the dosage-balanced …

Global Change Effects On Plant Communities Are Magnified By Time And The Number Of Global Change Factors Imposed, Kimberly J. Komatsu, Meghan L. Avolio, Nathan P. Lemoine, Forest Isbell, Emily Grman, Gregory R. Houseman, Sally E. Koerner, David S. Johnson, Kevin R. Wilcox, Juha M. Alatalo, John P. Anderson, Rien Aerts, Sara G. Baer, Andrew H. Baldwin, Jonathan Bates, Carl Beierkuhnlein, R. Travis Belote, John Blair, Juliette M.G. Bloor, Patrick J. Bohlen, Edward W. Bork, Elizabeth H. Boughton, William D. Bowman, Andrea J. Britton, James F. Cahill Jr., Enrique Chaneton, Nona R. Chiariello, Jimin Cheng, Scott L. Collins, J. Hans C. Cornelissen, Guozhen Du, Anu Eskelinen, Jennifer Firn, Bryan Foster, Laura Gough, Katherine Gross, Lauren M. Hallett, Xingguo Han, Harry Harmens, Mark J. Hovenden, Annika Jagerbrand, Anke Jentsch, Christel Kern, Kari Klanderud, Alan K. Knapp, Juergen Kreyling, Wei Li, Yiqi Luo, Rebecca L. Mcculley, Jennie R. Mclaren, J. Patrick Megonigal, John W. Morgan, Vladimir Onipchenko, Steven C. Pennings, Janet S. Prevéy, Jodi N. Price, Peter B. Reich, Clare H. Robinson, F. Leland Russell, Osvaldo E. Sala, Eric W. Seabloom, Melinda D. Smith, Nadejda A. Soudzilovskaia, Lara Souza, Katherine Suding, K. Blake Suttle, Tony Svejcar, David Tilman, Pedro Tognetti, Roy Turkington, Shannon White, Zhuwen Xu, Laura Yahdjian, Qiang Yu, Pengfei Zhang, Yunhai Zhang

Biological Sciences Faculty Research and Publications

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (y). In contrast, long-term (≥10 y) experiments show increasing community …

The Transcriptome Of The Veiled Chameleon (Chamaeleo Calyptratus): A Resource For Studying The Evolution And Development Of Vertebrates, Brendan John Pinto, Daren C. Card, Todd A. Castoe, Raul E. Diaz Jr., Stuart V. Nielsen, Paul A. Trainor, Tony Gamble

Biological Sciences Faculty Research and Publications

Purpose

The veiled chameleon (Chamaeleo calyptratus) is an emerging model system for studying functional morphology and evolutionary developmental biology (evo‐devo). Chameleons possess body plans that are highly adapted to an arboreal life style, featuring laterally compressed bodies, split hands/ft for grasping, a projectile tongue, turreted independently moving eyes, and a prehensile tail. Despite being one of the most phenotypically divergent clades of tetrapods, genomic resources for chameleons are severely lacking.

Methods

To address this lack of resources, we used RNAseq to generate 288 million raw Illumina sequence reads from four adult tissues (male and female eyes and gonads) …

Semi-Automatic Extraction Of Liana Stems From Terrestrial Lidar Point Clouds Of Tropical Rainforests, Sruthi M. Krishna Moorthy, Yunfei Bao, Kim Calders, Stefan A. Schnitzer, Hans Verbeeck

Biological Sciences Faculty Research and Publications

Lianas are key structural elements of tropical forests having a large impact on the global carbon cycle by reducing tree growth and increasing tree mortality. Despite the reported increasing abundance of lianas across neotropics, very few studies have attempted to quantify the impact of lianas on tree and forest structure. Recent advances in high resolution terrestrial laser scanning (TLS) systems have enabled us to quantify the forest structure, in an unprecedented detail. However, the uptake of TLS technology to study lianas has not kept up with the same pace as it has for trees. The slower technological adoption of TLS …

Modeling The Impact Of Liana Infestation On The Demography And Carbon Cycle Of Tropical Forests, Manfredo Di Porcia E Brugnera, Félicien Meunier, Marcos Longo, Sruthi M. Krishna Moorthy, Hannes De Deurwaerder, Stefan A. Schnitzer, Damien Bonal, Boris Faybishenko, Hans Verbeeck

Biological Sciences Faculty Research and Publications

There is mounting empirical evidence that lianas affect the carbon cycle of tropical forests. However, no single vegetation model takes into account this growth form, although such efforts could greatly improve the predictions of carbon dynamics in tropical forests. In this study, we incorporated a novel mechanistic representation of lianas in a dynamic global vegetation model (the Ecosystem Demography Model). We developed a liana‐specific plant functional type and mechanisms representing liana–tree interactions (such as light competition, liana‐specific allometries, and attachment to host trees) and parameterized them according to a comprehensive literature meta‐analysis. We tested the model for an old‐growth forest …

Evolution Of The Gekkotan Adhesive System: Does Digit Anatomy Point To One Or More Origins?, Anthony P. Russell, Tony Gamble

Biological Sciences Faculty Research and Publications

Recently-developed, molecularly-based phylogenies of geckos have provided the basis for reassessing the number of times adhesive toe-pads have arisen within the Gekkota. At present both a single origin and multiple origin hypotheses prevail, each of which has consequences that relate to explanations about digit form and evolutionary transitions underlying the enormous variation in adhesive toe pad structure among extant, limbed geckos (pygopods lack pertinent features). These competing hypotheses result from mapping the distribution of toe pads onto a phylogenetic framework employing the simple binary expedient of whether such toe pads are present or absent. It is evident, however, that adhesive …