Ecology and Evolutionary Biology Commons^™

Comparative Genomics Explains The Evolutionary Success Of Reef-Forming Corals, Debashish Bhattacharya, Shobhit Agrawal, Manuel Aranda, Sebastian Baumgarten, Mahdi Belcaid, Jeana L. Drake, Douglas Erwin, Sylvian Foret, Ruth D. Gates, David F. Gruber, Bishoy Kamel, Michael P. Lesser, Oren Levy, Yi Jin Liew, Matthew Macmanes, Tali Mass, Monica Medina, Shaadi Mehr, Eli Meyer, Dana C. Price, Hollie M. Putnam, Huan Qiu, Chuya Shinzato, Eiichi Shoguchi, Alexander J. Stokes, Sylvie Tambutté, Dan Tchernov, Christian R. Voolstra, Nicole Wagner, Charles W. Walker, Andreas Pm Weber, Virginia Weis, Ehud Zelzion, Didier Zoccola, Paul G. Falkowski

Publications and Research

Transcriptome and genome data from twenty stony coral species and a selection of reference bilaterians were studied to elucidate coral evolutionary history. We identified genes that encode the proteins responsible for the precipitation and aggregation of the aragonite skeleton on which the organisms live, and revealed a network of environmental sensors that coordinate responses of the host animals to temperature, light, and pH. Furthermore, we describe a variety of stress-related pathways, including apoptotic pathways that allow the host animals to detoxify reactive oxygen and nitrogen species that are generated by their intracellular photosynthetic symbionts, and determine the fate of corals …

Biofluorescence In Catsharks (Scyliorhinidae): Fundamental Description And Relevance For Elasmobranch Visual Ecology, David F. Gruber, Ellis R. Loew, Dimitri D. Deheyn, Derya Akkaynak, Jean P. Gaffney, W. Leo Smith, Matthew P. Davis, Jennifer H. Stern, Vincent A. Pieribone, John S. Sparks

Publications and Research

Biofluorescence has recently been found to be widespread in marine fishes, including sharks. Catsharks, such as the Swell Shark (Cephaloscyllium ventriosum) from the eastern Pacific and the Chain Catshark (Scyliorhinus retifer) from the western Atlantic, are known to exhibit bright green fluorescence. We examined the spectral sensitivity and visual characteristics of these reclusive sharks, while also considering the fluorescent properties of their skin. Spectral absorbance of the photoreceptor cells in these sharks revealed the presence of a single visual pigment in each species. Cephaloscyllium ventriosum exhibited a maximum absorbance of 484 ± 3 nm and an absorbance range at half …

Diversity-Dependent Cladogenesis Throughout Western Mexico: Evolutionary Biogeography Of Rattlesnakes (Viperidae: Crotalinae: Crotalus And Sistrurus), Christopher Blair, Santiago Sánchez-Ramírez

Publications and Research

Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the …

Review Paper: The Shape Of Phylogenetic Treespace, Katherine St. John

Publications and Research

Trees are a canonical structure for representing evolutionary histories. Many popular criteria used to infer optimal trees are computationally hard, and the number of possible tree shapes grows super-exponentially in the number of taxa. The underlying structure of the spaces of trees yields rich insights that can improve the search for optimal trees, both in accuracy and in running time, and the analysis and visualization of results. We review the past work on analyzing and comparing trees by their shape as well as recent work that incorporates trees with weighted branch lengths.

Eggshell Pigment Composition Covaries With Phylogeny, Kaat Brulez, Ivan Miksik, Christopher R. Cooney, Mark E. Hauber, Paul George Lovell, Golo Maurer, Steven J. Portugal, Douglas Russell, Silas James Reynolds, Phillip Cassey

Publications and Research

No single hypothesis is likely to explain the diversity in eggshell coloration and patterning across birds, suggesting that eggshell appearance is most likely to have evolved to fulfill many nonexclusive functions. By controlling for nonindependent phylogenetic associations between related species, we describe this diversity using museum eggshells of 71 British breeding passerine species to examine how eggshell pigment composition and concentrations vary with phylogeny and with life-history and nesting ecology traits. Across species, concentrations of biliverdin and protoporphyrin, the two main pigments found in eggshells, were strongly and positively correlated, and both pigments strongly covaried with phylogenetic relatedness. Controlling for …

Editorial: Systems Biology And Ecology Of Microbial Mat Communities, Martin G. Klotz, Donald A. Bryant, Jim K. Fredrickson, William P. Inskeep, Michael Kühl

Publications and Research

No abstract provided.

Are We Overestimating The Niche? Removing Marginal Localities Helps Ecological Niche Models Detect Environmental Barriers, Mariano Soley-Guardia, Eliécer E. Gutiérrez, Darla M. Thomas, José Ochoa-G, Marisol Aguilera, Robert P. Anderson

Publications and Research

Correlative ecological niche models (ENMs) estimate species niches using occurrence records and environmental data. These tools are valuable to the field of biogeography, where they are commonly used to infer potential connectivity among populations. However, a recent study showed that when locally relevant environmental data are not available, records from patches of suitable habitat protruding into otherwise unsuitable regions (e.g., gallery forests within dry areas) can lead to overestimations of species niches and their potential distributions. Here, we test whether this issue obfuscates detection of an obvious environmental barrier existing in northern Venezuela – that of the hot and xeric …

Comparative Phylogeography Of Ethiopian Anurans: Impact Of The Great Rift Valley And Pleistocene Climate Change, Xenia Freilich, Jose D. Anadon, Jolanta Bukala, Ordaliza Calderon, Ronveer Chakraborty, Stephanie Boissinot

Publications and Research

Background: The Ethiopian highlands are a biodiversity hotspot, split by the Great Rift Valley into two distinct systems of plateaus and mountains. The Rift Valley is currently hot and dry and acts as a barrier to gene flow for highland-adapted species. It is however unlikely that the conditions in the Rift were inhospitable to highland species during the entire Pleistocene. To assess the significance of the Ethiopian Rift as a biogeographic barrier as well as the impact Pleistocene climatic changes have had on the evolution of Ethiopian organisms, we performed phylogeographic analyses and developed present and past niche models on …

Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Et Al.

Publications and Research

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot and lower …

A Generalist Brood Parasite Modifies Use Of A Host In Response To Reproductive Success, Matthew I M Louder, Wendy M. Schelsky, Amber N. Albores, Jeffrey P. Hoover

Publications and Research

Avian obligate brood parasites, which rely solely on hosts to raise their young, should choose the highest quality hosts to maximize reproductive output. Brown-headed cowbirds (Molothrus ater) are extreme host generalists, yet female cowbirds could use information based on past reproductive outcomes to make egg-laying decisions thus minimizing fitness costs associated with parasitizing low quality hosts. We use a long-term (21 years) nest box study of a single host, the prothonotary warbler (Protonotaria citrea), to show that local cowbird reproductive success, but not host reproductive success, was positively correlated with the probability of parasitism the following …

Population Genetic Structure Of The Dwarf Seahorse (Hippocampus Zosterae) In Florida, Nathan Fedrizzi, Melanie L. J. Stiassny, J. T. Boehm, Eric R. Dougherty, George Amato, Martin Mendez

Publications and Research

The dwarf seahorse (Hippocampus zosterae) is widely distributed throughout near-shore habitats of the Gulf of Mexico and is of commercial significance in Florida, where it is harvested for the aquarium and curio trades. Despite its regional importance, the genetic structure of dwarf seahorse populations remains largely unknown. As an aid to ongoing conservation efforts, we employed three commonly applied mtDNA markers (ND4, DLoop and CO1) to investigate the genetic structuring of H. zosterae in Florida using samples collected throughout its range in the state. A total of 1450 bp provided sufficient resolution to delineate four populations of dwarf seahorses, as …

Common Cell Shape Evolution Of Two Nasopharyngeal Pathogens, Frédéric J. Veyrier, Nicolas Biais, Pablo Morales, Nouria Belkacem, Cyril Guilhen, Sylvia Ranjeva, Odile Sismeiro, Gérard Péhau-Arnaudet, Eduardo P. Rocha, Catherine Werts, Muhamed-Kheir Taha, Ivo G. Boneca

Publications and Research

Respiratory infectious diseases are the third cause of worldwide death. The nasopharynx is the portal of entry and the ecological niche of many microorganisms, of which some are pathogenic to humans, such as Neisseria meningitidis and Moraxella catarrhalis. These microbes possess several surface structures that interact with the actors of the innate immune system. In our attempt to understand the past evolution of these bacteria and their adaption to the nasopharynx, we first studied differences in cell wall structure, one of the strongest immune-modulators. We were able to show that a modification of peptidoglycan (PG) composition (increased proportion of pentapeptides) …

Estimates Of Micro-, Nano-, And Picoplankton Contributions To Particle Export In The Northeast Pacific, B. L. Mackinson, S. B. Moran, M. W. Lomas, Gillian M. Stewart, R. P. Kelly

Publications and Research

The contributions of micro-, nano-, and picoplankton to particle export were estimated from measurements of size-fractionated particulate 234Th, organic carbon, and phytoplankton indicator pigments obtained during five cruises between 2010 and 2012 along Line P in the subarctic northeast Pacific Ocean. Sinking fluxes of particulate organic carbon (POC) and indicator pigments were calculated from 234Th;238U disequilibria and, during two cruises, measured by a sediment trap at Ocean Station Papa. POC fluxes at 100m ranged from 0.65 to 7.95 mmolm2 d1, similar in magnitude to previous results at Line P. Microplankton pigments dominate indicator pigment fluxes (averaging 6919% of total pigment …

Molecular Diversity And Gene Evolution Of The Venom Arsenal Of Terebridae Predatory Marine Snails, Juliette Gorson, Girish Ramrattan, Aida Verdes, Elizabeth M. Wright, Yuri Kantor, Ramakrishnan Rajaram Srinivasan, Raj Musunuri, Daniel Packer, Gabriel Albano, Wei-Gang Qiu, Mandë Holford

Publications and Research

Venom peptides from predatory organisms are a resource for investigating evolutionary processes such as adaptive radiation or diversification, and exemplify promising targets for biomedical drug development. Terebridae are an understudied lineage of conoidean snails,which also includes cone snails and turrids. Characterization of cone snail venompeptides, conotoxins, has revealed a cocktail of bioactive compounds used to investigate physiological cellular function, predator-prey interactions, and to develop novel therapeutics. However, venom diversity of other conoidean snails remains poorly understood. The present research applies a venomics approach to characterize novel terebrid venom peptides, teretoxins, from the venom gland transcriptomes of Triplostephanus anilis and Terebra …

Using 3d Printed Eggs To Examine The Egg-Rejection Behaviour Of Wild Birds, Branislav Igic, Valerie Nunez, Henning U. Voss, Rebecca Croston, Zachary Aidala, Analía V. López, Aimee Van Tatenhove, Mandë E. Holford, Matthew D. Shawkey, Mark E. Hauber

Publications and Research

The coevolutionary relationships between brood parasites and their hosts are often studied by examining the egg rejection behaviour of host species using artificial eggs. However, the traditional methods for producing artificial eggs out of plasticine, plastic, wood, or plaster-of-Paris are laborious, imprecise, and prone to human error. As an alternative, 3D printing may reduce human error, enable more precise manipulation of egg size and shape, and provide a more accurate and replicable protocol for generating artificial stimuli than traditional methods. However, the usefulness of 3D printing technology for egg rejection research remains to be tested. Here, we applied 3D printing …

Teaching Evolution: A Students’ Perspective, Abdullah Allaoa, Tyniqua Hinton

Publications and Research

Many may wonder “where do we come from?” Over time, scientists have pondered and tested the concept of evolution. Simply put, evolution is gradual change over time. A major tenet of evolution is natural selection, which includes three principles which are variation in population, differential reproduction due to competition, and heredity. These principles are supported by multiple lines of evidence, including biochemical, geographical, fossil, and anatomical evidence. By providing tangible, real-world examples of evolution, we hope to provide a clear understanding of this long-studied scientific breakthrough, while at the same time showing how animals (including us) are related to each …

Climate And Changing Winter Distribution Of Alcids In The Northwest Atlantic, Richard R. Veit, Lisa L. Manne

Publications and Research

Population level impacts upon seabirds from changing climate are increasingly evident, and include effects on phenology, migration, dispersal, annual survivorship, and reproduction. Most population data on seabirds derive from nesting colonies; documented climate impacts on winter ecology are scarce. We studied interannual variability in winter abundance of six species of alcids (Charadriiformes, Alcidae) from a 58-year time series of data collected in Massachusetts 1954–2011. We used counts of birds taken during fall and winter from coastal vantage points. Counts were made by amateur birders, but coverage was consistent in timing and location. We found significant association between winter abundance of …

Experimental Shifts In Intraclutch Egg Color Variation Do Not Affect Egg Rejection In A Host Of A Non-Egg-Mimetic Avian Brood Parasite, Rebecca Croston, Mark E. Hauber

Publications and Research

Avian brood parasites lay their eggs in the nests of other birds, and impose the costs associated with rearing parasitic young onto these hosts. Many hosts of brood parasites defend against parasitism by removing foreign eggs from the nest. In systems where parasitic eggs mimic host eggs in coloration and patterning, extensive intraclutch variation in egg appearances may impair the host’s ability to recognize and reject parasitic eggs, but experimental investigation of this effect has produced conflicting results. The cognitive mechanism by which hosts recognize parasitic eggs may vary across brood parasite hosts, and this may explain variation in experimental …

Now You See It, Now You Don’T: Flushing Hosts Prior To Experimentation Can Predict Their Responses To Brood Parasitism, Daniel Hanley, Peter Samas, Josef Heryán, Mark E. Hauber, Tomáš Grim

Publications and Research

Brood parasitic birds lay their eggs in other birds’ nests, leaving hosts to raise their offspring. To understand parasite-host coevolutionary arms races, many studies have examined host responses to experimentally introduced eggs. However, attending parents often need to be flushed from their nests to add experimental eggs. If these birds witness parasitism events, they may recognize and reject foreign eggs more readily than parents who did not. We found that, after being flushed, female blackbirds, Turdus merula, remained close to their nests. Flushed females were more likely to eject foreign eggs and did so more quickly than females that …

Striking The Balance: Challenges And Perspectives For The Protected Areas Network In Northeastern European Russia, Svetlana V. Degteva, Vasily I. Ponomarev, Sasha W. Eisenman, Vyacheslav Dushenkov

Publications and Research

Increasing anthropogenic pressure on the largest remaining tracts of old-growth boreal forest in Europe necessitates additional conservation of ecosystems and biodiversity in northeastern European Russia. In a regional network comprising 8 % of the Nenets Autonomous District and 13.5 % of the Komi Republic, 248 areas have varying protected statuses as state nature reserves (zapovedniks), national parks, reserves/sanctuaries (zakazniks), or natural monuments. Due to increased natural resource extraction in this relatively pristine area, designation of additional protected areas is critical for the protection of key ecological sites. The history of ecological preservation in these regions is herein described, and recent …

High Intralocus Variability And Interlocus Recombination Promote Immunological Diversity In A Minimal Major Histocompatibility System, Anthony B. Wilson, Camilla M. Whittington, Angela Bahr

Publications and Research

Background: The genes of the major histocompatibility complex (MHC/MH) have attracted considerable scientific interest due to their exceptional levels of variability and important function as part of the adaptive immune system. Despite a large number of studies on MH class II diversity of both model and non-model organisms, most research has focused on patterns of genetic variability at individual loci, failing to capture the functional diversity of the biologically active dimeric molecule. Here, we take a systematic approach to the study of MH variation, analyzing patterns of genetic variation at MH class IIα and IIβ loci of the seahorse, which …

High Local Diversity Of Trypanosoma In A Common Bat Species, And Implications For The Biogeography And Taxonomy Of The T. Cruzi Clade, Veronika M. Cottontail, Elisabeth K. V. Kalko, Iain Cottontail, Nele Wellinghausen, Marco Tschapka, Susan L. Perkins, C. Miguel Pinto

Publications and Research

The Trypanosoma cruzi clade is a group of parasites that comprises T. cruzi sensu lato and its closest relatives. Although several species have been confirmed phylogenetically to belong to this clade, it is uncertain how many more species can be expected to belong into this group. Here, we present the results of a survey of trypanosome parasites of the bat Artibeus jamaicensis from the Panama´ Canal Zone, an important seed disperser. Using a genealogical species delimitation approach, the Poisson tree processes (PTP), we tentatively identified five species of trypanosomes – all belonging to the T. cruzi clade. A small monophyletic …

Nesting Behaviour Influences Species-Specific Gas Exchange Across Avian Eggshells, Steven J. Portugal, Golo Maurer, Gavin H. Thomas, Mark E. Hauber, Tomáš Grim, Phillip Cassey

Publications and Research

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (GH2O) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell GH2O and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in GH2O has evolved to maintain optimal water loss across a diverse set of nest environments. …

Naïve Hosts Of Avian Brood Parasites Accept Foreign Eggs, Whereas Older Hosts Fine-Tune Foreign Egg Discrimination During Laying, Csaba Moskát, Miklós Bán, Mark E. Hauber

Publications and Research

Background: Many potential hosts of social parasites recognize and reject foreign intruders, and reduce or altogether escape the negative impacts of parasitism. The ontogenetic basis of whether and how avian hosts recognize their own and the brood parasitic eggs remains unclear. By repeatedly parasitizing the same hosts with a consistent parasitic egg type, and contrasting the responses of naïve and older breeders, we studied ontogenetic plasticity in the rejection of foreign eggs by the great reed warbler (Acrocephalus arundinaceus), a host species of the common cuckoo (Cuculus canorus).

Results: In response to experimental parasitism before the …

Comparative Population Assessments Of Nautilus Sp. In The Philippines, Australia, Fiji, And American Samoa Using Baited Remote Underwater Video Systems, Gregory Jeff Barord, Frederick Dooley, Andrew Dunstan, Anthony Ilano, Karen N. Keister, Heike Neumeister, Thomas Preuss, Shane Schoepfer, Peter D. Ward

Publications and Research

The extant species of Nautilus and Allonautilus (Cephalopoda) inhabit fore-reef slope environments across a large geographic area of the tropical western Pacific and eastern Indian Oceans. While many aspects of their biology and behavior are now well-documented, uncertainties concerning their current populations and ecological role in the deeper, fore-reef slope environments remain. Given the historical to current day presence of nautilus fisheries at various locales across the Pacific and Indian Oceans, a comparative assessment of the current state of nautilus populations is critical to determine whether conservation measures are warranted. We used baited remote underwater video systems (BRUVS) to make …

Early Back-To-Africa Migration Into The Horn Of Africa, Jason A. Hodgson, Connie J. Mulligan, Ali Al-Meeri, Ryan L. Raaum

Publications and Research

Genetic studies have identified substantial non-African admixture in the Horn of Africa (HOA). In the most recent genomic studies, this non-African ancestry has been attributed to admixture with Middle Eastern populations during the last few thousand years. However, mitochondrial and Y chromosome data are suggestive of earlier episodes of admixture. To investigate this further, we generated new genome-wide SNP data for a Yemeni population sample and merged these new data with published genome-wide genetic data from the HOA and a broad selection of surrounding populations. We used multidimensional scaling and ADMIXTURE methods in an exploratory data analysis to develop hypotheses …

Mafia Or Farmer? Coevolutionary Consequences Of Retaliation And Farming As Predator Strategies Upon Host Nests By Avian Brood Parasites, Mark E. Hauber

Publications and Research

Many host species of avian brood parasites have evolved to recognize and reject foreign eggs and chicks in the nest. Yet, other hosts accept and care for parasitic young, despite the fitness losses associated with raising non-kin. It has been suggested that nest predation upon host nests by brood parasites could select for coevolved acceptance by hosts, even when their cognitive and motor traits allow for the successful rejection of brood parasitism. Using a modeling approach, I analyzed the conditions that favor the evolution of two predatory strategies by parasites and the acceptance of parasitism in the presence of predatory …

Host Responses To Interspecific Brood Parasitism: A By-Product Of Adaptations To Conspecific Parasitism?, Peter Samas, Mark E. Hauber, Phillip Cassey, Tomáš Grim

Publications and Research

Background: Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host’s ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with …

The Evolutionary Function Of Conscious Information Processing Is Revealed By Its Task-Dependency In The Olfactory System, Andreas Keller

Publications and Research

Although many responses to odorous stimuli are mediated without olfactory information being consciously processed, some olfactory behaviors require conscious information processing. I will here contrast situations in which olfactory information is processed consciously to situations in which it is processed non-consciously. This contrastive analysis reveals that conscious information processing is required when an organism is faced with tasks in which there are many behavioral options available. I therefore propose that it is the evolutionary function of conscious information processing to guide behaviors in situations in which the organism has to choose between many possible responses.

2matrix: A Utility For Indel Coding And Phylogenetic Matrix Concatenation, Nelson R. Salinas, Damon P. Little

Publications and Research

Premise of the study: Phylogenetic analysis of DNA and amino acid sequences requires the creation of files formatted specifically for each analysis package. Programs currently available cannot simultaneously code inferred insertion/deletion (indel) events in sequence alignments and concatenate data sets.

Methods and Results: A novel Perl script, 2matrix, was created to concatenate matrices of non-molecular characters and/or aligned sequences and to code indels. 2matrix outputs a variety of formats compatible with popular phylogenetic programs.

Conclusions: 2matrix efficiently codes indels and concatenates matrices of sequences and non-molecular data. It is available for free download under a GPL (General Public License) open …