Animal Sciences Commons^™

Methylene Blue Inhibits Cromakalim-Activated K+ Currents In Follicle-Enclosed Oocytes, Dmytro Isaev, Keun-Hang Susan Yang, Georg Petroianu, Dietrich Ernst Lorke, Murat Oz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The effects of methylene blue (MB) on cromakalim-induced K⁺ currents were investigated in follicle-enclosed Xenopus oocytes. In concentrations ranging from 3–300 μM, MB inhibited K⁺ currents (IC₅₀: 22.4 μM) activated by cromakalim, which activates K_ATP channels. MB inhibited cromakalim-activated K⁺ currents in a noncompetitive and voltage-independent manner. The respective EC₅₀ and slope values for cromakalim-activation of K⁺ currents were 194 ± 21 µM and 0.91 for controls, and 206 ± 24 µM and 0.87 in the presence of 30 μM MB. The inhibition of cromakalim-induced K⁺ currents by MB was not …

Female Presence Does Not Increase Testosterone But Still Ameliorates Sickness Behaviours In Male Japanese Quail, Brenna M. G. Gormally, Kaelyn Bridgette, Aubrey Emmi, Delilah Schuerman, Patricia C. Lopes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Infections can dramatically modify animal behaviour. The extent of these changes depends on an animal's environment. It has been proposed that testosterone modulates the suppression of behavioural symptoms of sickness under certain reproductive contexts. To further understand the role played by testosterone in modulating sickness behaviours under reproductive contexts, we studied a species, the Japanese quail, in which female exposure rapidly decreases circulating testosterone in males. Males received either an immune challenge (lipopolysaccharide – LPS) or a control injection and their behaviours, mass change and testosterone levels were quantified in the presence or absence of a female. Both the presence …

Reckless Parenting With A Purpose, Walter H. Piper, Linda Grenzer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

No abstract provided.

Neurotranscriptomic Changes Associated With Chick-Directed Parental Care In Adult Non-Reproductive Japanese Quail, Patricia C. Lopes, Robert De Brujin

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

For many species, parental care critically affects offspring survival. But what drives animals to display parental behaviours towards young? In mammals, pregnancy-induced physiological transformations seem key in preparing the neural circuits that lead towards attraction (and reduced-aggression) to young. Beyond mammalian maternal behaviour, knowledge of the neural mechanisms that underlie young-directed parental care is severely lacking. We took advantage of a domesticated bird species, the Japanese quail, for which parental behaviour towards chicks can be induced in virgin non-reproductive adults through a sensitization procedure, a process that is not effective in all animals. We used the variation in parental responses …

Functional Morphology Of Gliding Flight Ii. Morphology Follows Predictions Of Gliding Performance, Jonathan Rader, Tyson L. Hedrick, Yanyan He, Lindsay D. Waldrop

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The evolution of wing morphology among birds, and its functional consequences, remains an open question, despite much attention. This is in part because the connection between form and function is difficult to test directly. To address this deficit, in prior work we used computational modeling and sensitivity analysis to interrogate the impact of altering wing aspect ratio, camber, and Reynolds number on aerodynamic performance, revealing the performance landscapes that avian evolution has explored. In the present work, we used a dataset of three-dimensionally scanned bird wings coupled with the performance landscapes to test two hypotheses regarding the evolutionary diversification of …

Plunging Floater Survival Causes Cryptic Population Decline In The Common Loon, Walter H. Piper, Jason Grear, Brian Hoover, Elaina Lomery, Linda M. Grenzer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Populations of many vertebrates are declining and geographic ranges contracting, largely as a consequence of anthropogenic threats. Many reports of such decline, however, lack the breadth and detail to narrow down its causes. Here we describe population decline in the Common Loon (Gavia immer), a charismatic aquatic bird, based on systematic resighting and measurement of a marked population. During our 27-year investigation, age-adjusted chick mass has fallen by 11%, mortality among young and old chicks has increased by 31% and 82%, respectively, and fledging success has declined by 26%. Meanwhile, the return rate of marked nonbreeders (“floaters”) has …

Functional Morphology Of Gliding Flight I. Modeling Reveals Distinct Performance Landscapes Based On Soaring Strategies, Lindsay D. Waldrop, Yanyan He, Tyson L. Hedrick, Jonathan Rader

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The physics of flight influences the morphology of bird wings through natural selection on flight performance. The connection between wing morphology and performance is unclear due to the complex relationships between various parameters of flight. In order to better understand this connection, we present a holistic analysis of gliding flight that preserves complex relationships between parameters. We use a computational model of gliding flight, along with analysis by uncertainty quantification, to 1) create performance landscapes of gliding based on output metrics (maximum lift-to-drag ratio, minimum gliding angle, minimum sinking speed, lift coefficient at minimum sinking speed); and 2) predict what …

Immune-Endocrine Links To Gregariousness In Wild House Mice, Patricia C. Lopes, Esther H. D. Carlitz, Morgan Kindel, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Social interactions are critically important for survival and impact overall-health, but also impose costs on animals, such as exposure to contagious agents. The immune system can play a critical role in modulating social behavior when animals are sick, as has been demonstrated within the context of “sickness behaviors.” Can immune molecules affect or be affected by social interactions even when animals are not sick, therefore serving a role in mediating pathogen exposure? We tested whether markers of immune function in both the blood and the brain are associated with gregariousness, quantified as number of animals interacted with per day. To …

Common Loons Respond Adaptively To A Black Fly That Reduces Nesting Success, Walter H. Piper, Keren B. Tischler, Andrew Reinke

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nesting birds must often cope with harassment from biting insects, but it is difficult to ascertain what effect such pests might have on breeding success and population dynamics. We tested the hypothesis that a black fly (Simulium annulus) that feeds on the blood of nesting Common Loons (Gavia immer) causes nest abandonment in this charismatic diving bird. In addition, we measured effects of fly-induced abandonment on a loon population, and examined potential predictors of fly abundance and nest abandonment. We also tested a second hypothesis, which holds that loon pairs that abandon a nest owing to …

Emptying And Refilling Of Slime Glands In Atlantic (Myxine Glutinosa) And Pacific (Eptatretus Stoutii) Hagfishes, Sarah Schorno, Todd E. Gillis, Douglas S. Fudge

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hagfishes are known for their unique defensive slime, which they use toward off gill-breathing predators. Although much is known about the slime cells (gland thread cells and gland mucous cells), little is known about how long slime gland refilling takes, or how slime composition changes with refilling or repeated stimulation of the same gland. Slime glands can be individually electrostimulated to release slime, and this technique was used to measure slime gland refilling times for Atlantic and Pacific hagfish. The amount of exudate produced, the composition of the exudate and the morphometrics of slime cells were analyzed during refilling, and …

The Long Shadow Of Senescence: Age Impacts Survival And Territory Defense In Loons, Walter H. Piper, Kristin M. Brunk, Joel A. Flory, Michael W. Meyer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Senescence, increased mortality that occurs among animals of advanced age, impacts behavior and ecology in many avian species. We investigated actuarial, reproductive, and behavioral senescence using capture, marking, and resighting data from a 26-year study of common loons (Gavia immer). Territorial residents of both sexes exhibited high annual survival (0.94) until their mid 20s, at which point survival fell to 0.76 and 0.77 in males and females, respectively. Sexual symmetry in actuarial senescence is somewhat surprising in this species, because males make a substantially greater investment in territory defense and chick-rearing and because males engage in lethal contests for territory …

Rapid Increase In Genetic Diversity In An Endemic Patagonian Tuco-Tuco Following A Recent Volcanic Eruption, Jeremy L. Hsu, Sharon Kam, Mauro N. Tammone, Eileen A. Lacey, Elizabeth A. Hadly

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Catastrophic natural events can have profound impacts on patterns of genetic diversity. Due to the typically unpredictable nature of such phenomena, however, few studies have been able to directly compare patterns of diversity before and after natural catastrophic events. Here, we examine the impacts of a recent volcanic eruption in southern Chile on genetic variation in the colonial tuco-tuco (Ctenomys sociabilis), a subterranean species of rodent endemic to the area most affected by the June 2011 eruption of the Puyehue-Cordón Caulle volcanic complex. To provide a comparative context for interpreting changes in genetic variation in this species, we …

Skeletal Stiffening In An Amphibious Fish Out Of Water Is A Response To Increased Body Weight, Andy J. Turko, Dietmar KüLtz, Douglas S. Fudge, Roger P. Croll, Frank M. Smith, Matthew R. Stoyek, Patricia A. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Terrestrial animals must support their bodies against gravity, while aquatic animals are effectively weightless because of buoyant support from water. Given this evolutionary history of minimal gravitational loading of fishes in water, it has been hypothesized that weight-responsive musculoskeletal systems evolved during the tetrapod invasion of land and are thus absent in fishes. Amphibious fishes, however, experience increased effective weight when out of water – are these fishes responsive to gravitational loading? Contrary to the tetrapod-origin hypothesis, we found that terrestrial acclimation reversibly increased gill arch stiffness (∼60% increase) in the amphibious fish Kryptolebias marmoratus when loaded normally by gravity, …

Connecting Model Species To Nature: Predator-Induced Long-Term Sensitization In Aplysia Californica, Maria J. Mason, Amanda J. Watkins, Jordann Wakabayashi, Jennifer Buechler, Christine Pepino, Michelle Brown, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Previous research on sensitization in Aplysia was based entirely on unnatural noxious stimuli, usually electric shock, until our laboratory found that a natural noxious stimulus, a single sublethal lobster attack, causes short-term sensitization. We here extend that finding by demonstrating that multiple lobster attacks induce long-term sensitization (>= 24 h) as well as similar, although not identical, neuronal correlates as observed after electric shock. Together these findings establish long-and short-term sensitization caused by sublethal predator attack as a natural equivalent to sensitization caused by artificial stimuli.

A Fish Out Of Water: Gill And Skin Remodeling Promotes Osmo- And Ionoregulation In The Mangrove Killifish Kryptolebias Marmoratus, Danielle M. Leblanc, Chris M. Wood, Douglas S. Fudge, Patricia A. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The euryhaline, amphibious mangrove killifish Kryptolebias marmoratus is known to survive weeks out of water in moist environments. We tested the hypothesis that the skin is a site of osmo- and ionoregulation in K. marmoratus. We predicted that under terrestrial conditions, gill and skin remodeling would result in an enhanced role for skin and a diminished role for the gills in osmo- and ionoregulation. Fish were exposed to water—either freshwater (FW, 1‰) or hypersaline water (saltwater [SW], 45‰)—or air over a moist surface of FW or SW for 9 d and then recovered in water. When fish were emersed …

Interspecific Variation In Palatability Suggests Cospecialization Of Antipredator Defenses In Sea Hares, Kimberly K. Takagi, Nadia N. Ono, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Prey species often deploy different kinds of antipredator defenses, which can interact with each other in ways that are not yet completely understood. Much research into these interactions has utilized gastropod mollusks, usually focusing (in part) on the protective utility of the gastropod shell. This makes the evolutionary reduction of the shell in the opisthobranch gastropods (marine slugs) particularly interesting. This loss of protective function of the shell is associated with the evolution of alternative defenses. Particularly well studied are chemical defenses, especially those using secondary metabolites derived from food resources. As a first step toward understanding interspecific variation in …

Lobster Attack Induces Sensitization In The Sea Hare, Aplysia Californica, Amanda J. Watkins, Daniel A. Goldstein, Lucy C. Lee, Christina J. Pepino, Scott L. Tillett, Francis E. Ross, Elizabeth M. Wilder, Virginia A. Zachary, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Studies of the neural mechanisms of learning, especially of sensitization, have benefitted from extensive research on the model species, Aplysia californica (hereafter Aplysia). Considering this volume of literature on mechanisms, it is surprising that our understanding of the ecological context of sensitization in Aplysia is completely lacking. Indeed, the widespread use of strong electric shock to induce sensitization (an enhancement of withdrawal reflexes following noxious stimulation) is completely unnatural and leaves unanswered the question of whether this simple form of learning has any ecological relevance. We hypothesized that sublethal attack by a co-occurring predator, the spiny lobster, Panulirus interruptus, might …

High Rate Of Recent Transposable Element–Induced Adaptation In Drosophila Melanogaster, Josefa Gonzalez, Kapa Lenkov, Mikhail Lipatov, J. Michael Macpherson, Dmitri A. Petrov

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Although transposable elements (TEs) are known to be potent sources of mutation, their contribution to the generation of recent adaptive changes has never been systematically assessed. In this work, we conduct a genome-wide screen for adaptive TE insertions in Drosophila melanogaster that have taken place during or after the spread of this species out of Africa. We determine population frequencies of 902 of the 1,572 TEs in Release 3 of the D. melanogaster genome and identify a set of 13 putatively adaptive TEs. These 13 TEs increased in population frequency sharply after the spread out of Africa. We argue that …

Similar Levels Of X-Linked And Autosomal Nucleotide Variation In African And Non-African Populations Of Drosophila Melanogaster, Nadia D. Singh, J. Michael Macpherson, Jeffrey D. Jensen, Dmitri A. Petrov

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Levels of molecular diversity in Drosophila have repeatedly been shown to be higher in ancestral, African populations than in derived, non-African populations. This pattern holds for both coding and noncoding regions for a variety of molecular markers including single nucleotide polymorphisms and microsatellites. Comparisons of X-linked and autosomal diversity have yielded results largely dependent on population of origin.

Results: In an attempt to further elucidate patterns of sequence diversity in Drosophila melanogaster, we studied nucleotide variation at putatively nonfunctional X-linked and autosomal loci in sub-Saharan African and North American strains of D. melanogaster. We combine our experimental …

Differential Classical Conditioning Of The Gill-Withdrawal Reflex In Aplysia Recruits Both Nmda Receptor-Dependent Enhancement And Nmda Receptor-Dependent Depression Of The Reflex, Shekib A. Jami, William G. Wright, David L. Glanzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Differential classical conditioning of the gill-withdrawal response (GWR) in Aplysia can be elicited by training in which a conditioned stimulus (CS) delivered to one side of the siphon (the CS+) is paired with a noxious unconditioned stimulus (US; tail shock), while a second conditioned stimulus (the CS-), delivered to a different siphon site, is unpaired with the US. NMDA receptor(NMDAR) activation has been shown previously to be critical for nondifferential classical conditioning in Aplysia. Here, we used a semi-intact preparation to test whether differential classical conditioning of the GWR also depends on activation of NMDARs. Differential training produced conditioned enhancement …

Associative Memory In Three Aplysiids: Correlation With Heterosynaptic Modulation, Brian A. Hoover, Hoang Nguyen, Laura Thompson, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Much recent research on mechanisms of learning and memory focuses on the role of heterosynaptic neuromodulatory signaling. Such neuromodulation appears to stabilize Hebbian synaptic changes underlying associative learning, thereby extending memory. Previous comparisons of three related sea-hares ( Mollusca, Opisthobranchia) uncovered interspecific variation in neuromodulatory signaling: strong in Aplysia californica, immeasureable in Dolabrifera dolabrifera, and intermediate in Phyllaplysia taylori. The present study addressed whether this interspecific variation in neuromodulation is correlated with memory of associative ( classical conditioning) learning. We differentially conditioned the tail-mantle withdrawal reflex of each of the three species: Mild touch to one side of the tail …