ART: Darwin's rhea by Diana Sudyka
Updated: 2009-10-19 22:09:58
Artist Diana Sudyka (blog), who did the logo for The HMS Beagle Project and another painting of Darw- Artist Diana Sudyka (blog), who did the logo for The HMS Beagle Project and another painting of Darw
The Physiology of Memory
Updated: 2009-10-19 16:02:16Ever since Richard Sermon coined the term engram, psychologists and neuroscientists in general have been looking for the physiological correlates of memory. One of the difficulties, of course, lies in measuring brain activity while the participant is laying down the memory trace. Researchers from Princeton University report on a study in which mice were placed on [...]Conservation: Minimum Population Size Targets Too Low To Prevent Extinction?
Updated: 2009-10-19 14:04:51SCIENCE DAILY – PRESS RELEASE That’s according to a new study by University of AdelaideChanging Academic Practice: Implications for Future Physical Sciences Academics, 4th November 2009, Lincoln EPA Science Centre, University of Oxford
Updated: 2009-10-19 10:09:27This workshop is organised jointly by the Physical Sciences Centre and the Preparing for Academic Practice Centre for Excellence in Teaching and Learning (CETL). It is a colloquium which aims to bring together doctoral students, postdoctoral researchers, and junior and senior academics, to explore and discuss the challenges and opportunities for those wishing to prepare [...]Endangered Atlantic bluefin tuna formally recommended for international trade ban
Updated: 2009-10-19 00:52:56THE DAILY STAR – LEBANONROME: The World Wildlife Fund welcomed on Thursday a proposal to ban #187; riginal newsNew Series: A Strange System: Food: The Stage is Set
Updated: 2009-10-19 00:49:03It has been a while since my last official series on this blog. Â I have been reading several books a #187; riginal newsScientists warn of increase in species extinctions
Updated: 2009-10-18 11:12:05NEWSPOSTONLINEScientists have warned of an alarming increase in the extinction of animal species, b #187; riginal newsSeeing Blue: Fish Vision Discovery Makes Waves In Evolutionary Biology
Updated: 2009-10-17 13:23:00Researchers have identified the first fish known to have switched from ultraviolet vision to violet vision, or the ability to see blue light. The discovery is also the first example of an animal deleting a molecule to change its visual spectrum. The findings on scabbardfish link molecular evolution to functional changes and the possible environmental factors driving them. #187; riginal newsCat's Eyes
Updated: 2009-10-17 13:20:55Part of my move to the Missouri River Valley included the acquisition of three cats. Or should I say #187; riginal newsJinns are Animals by Nature
Updated: 2009-10-17 13:18:04 Jinn: brief facts* The Arabic word âjinn' comes from the verb âjanna' which means âto hide or co #187; riginal newsChemical Imaging Of Deep-sea Microorganisms May Help Explain Lingering Nitrogen Mystery
Updated: 2009-10-17 10:05:18Researchers have identified an unexpected metabolic ability within a symbiotic community of microorganisms that may help solve a lingering mystery about the world's nitrogen cycling budget. #187; riginal newsScientists warn of increase in species extinctions
Updated: 2009-10-17 01:50:34NEWSPOSTONLINE Scientists have warned of an alarming increase in the extinction of animal species, bWhat is pathology?
Updated: 2009-10-16 15:53:13National Pathology Week (NPW) will hopefully answer this question and debunk many pathology myths during this week long event, which will be held from 02 November through 08th November. Events will be held across the country and the website provides some really interesting resources for students and a comprehensive listing of NPW events (can even be sorted by [...]Factors affecting methane production and mitigation in ruminants
Updated: 2009-10-16 14:41:41The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = [minus]17.766 + 42.793X [minus] 0.849X2, where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH4 inhibitors, and defaunation. Considering the... #187; riginal newsBug Barcode Readers Hold Out Promise Of Universal Vaccines
Updated: 2009-10-16 14:37:37Veterinary scientists have made a discovery that promises to deliver a new approach to fast development of cheap vaccines that are effective in all mammals -- not just humans or another particular species. #187; riginal newsVideo: My Boy Rascal 9.25.09 at Jack Sprat
Updated: 2009-10-16 14:36:40For those of you that missed MBR’s 9.25.09 show at Jack Sprat, you missed out on a great perfo #187; riginal newsSeasonal detection rates of river otters (Lontracanadensis) using bridge-site and random-site surveys
Updated: 2009-10-16 14:36:35S. M. Crimmins, N. M. Roberts, D. A. Hamilton, and A. R. Mynsberge - Randomization of survey sites is generally desired because of its unbiased approach, but is often abandoned because of logistical constraints. This is true for river... (Source: Canadian Journal of Zoology) #187; riginal newsUnderstanding of how insects smell
Updated: 2009-10-16 02:44:23New research announced recently, Wednesday 30th September, by a team of leading researchers working with the UK's national Synchrotron, Diamond Light Source, could have a significant impact on the development and refinement of new eco-friendly pest control methods for worldwide agriculture. Reported in the Journal of Molecular Biology, the study was carried out by Dr Jing-Jiang Zhou and his colleagues at the world's oldest agricultural research centre and the largest UK facility, Rothamsted Research, in collaboration with Professor Nick Keep's group from the Institute of Structural and Molecular Biology at Birkbeck, University of London........Conservation biologists setting their targets too low
Updated: 2009-10-16 02:44:23Conservation biologists are setting their minimum population size targets too low to prevent extinction. That's as per a newly released study by University of Adelaide and Macquarie University researchers which has shown that populations of endangered species are unlikely to persist in the face of global climate change and habitat loss unless they number around 5000 mature individuals or more........Energy Saving Week 19-25 October 2009
Updated: 2009-10-16 01:49:19Energy Saving Week runs next week from 19-25 October 2009. This year’s theme is Waste. Each day has been assigned a mini-theme: Monday: Wasteful behaviour & Launch day Tuesday: Warmer homes day (Insulation) Wednesday: Smarter driving day (Transport) Thursday: Switch off/turn down/turn off day Friday: Buy better day More information can be found on the Energy Saving Trust’s website, including more advice [...]Tiny But Adaptable Wasp Brains Show Ability To Alter Their Architecture
Updated: 2009-10-15 14:42:41For an animal that has a brain about the size of two grains of sand, a lot of plasticity seems to be packed into the head of the tropical paper wasp Polybia aequatorialis. #187; riginal newsSurprise find at city house
Updated: 2009-10-14 19:43:39THIRUVANANTHAPURAM: This little brown and yellowish orange spider has mistaken a city house at Maruthankuzhy for a moist deciduous forest. #187; riginal newsVegetarian spider discovered
Updated: 2009-10-14 19:38:56Spiders give me the creeps, so me blogging about one seems a bit odd… but it is still pretty c #187; riginal newsNew Type Of Flying Reptile: Darwin's Pterodactyl Preyed On Flying Dinosaurs
Updated: 2009-10-14 16:06:21Researchers have identified a new type of flying reptile, providing the first clear evidence of an unusual and controversial type of evolution. #187; riginal newsMicrochips Result In Higher Rate Of Return Of Shelter Animals To Owners
Updated: 2009-10-14 15:57:00Animals shelter officials housing lost pets that had been implanted with a microchip were able to find the owners in almost three out of four cases in a recently published national study. According to the research, the return-to-owner rate for cats was 20 times higher and for dogs 2.5 times higher for microchipped pets than were the rates of return for all stray cats and dogs that had entered the shelters. #187; riginal newsComplex Dynamics Based on a Quorum: Decision-Making Process by Cockroaches in a Patchy Environment
Updated: 2009-10-13 19:31:40This study on the cockroach species Periplaneta americana highlights a shelter-selection mechanism based on an amplification process resulting from the interactions between congeners. This mechanism leads to complex spatiotemporal aggregation dynamics characterized by transient bimodality, bifurcation patterns (shelter selection) and the existence of a quorum size in the settlement behaviour of the cockroaches. Finally, we discuss the generic aspect for other gregarious species of the collective decision-making process demonstrated for cockroaches. (Source: Ethology) #187; riginal newsDemographic and Genetic Constraints on Evolution
Updated: 2009-10-13 19:31:14: , , Zoology : Journals , Blogs , News and Stories Login Register Most Popular Most Recent Shopping Jobs Pictures Videos Submit a Story Back to NewsBeet Home Demographic and Genetic Constraints on Evolution Demographic and Genetic Constraints on Evolution Posted from MedWorm : Zoology 6 days ago Zoology Zoology News The American Naturalist , Volume 0, Issue 0, Page 000, Latest Articles . Abstract : Populations unable to evolve to selectively favored states are constrained . Genetic constraints occur when additive genetic variance in selectively favored directions is absent absolute constraints or present but small quantitative constraints Quantitative—unlike absolute—constraints are presumed surmountable given time . This ignores that a population might become extinct before reaching the favored state , in which case demography effectively converts a quantitative into an absolute constraint . Here . original story Add this link Tell a friend 7 views Add to : Bookmarks Recent News The Parotoplana jondelii species-group Platyhelminthes : Proseriata a microturbellarian radiation in the Mediterranean Bourgeois queens and high stakes games in the ant Aphaenogaster senilisLong Feared Extinct, Rare Bird Rediscovered
Updated: 2009-10-13 19:30:46Known to science only by two century-old specimens, a critically endangered crow has re-emerged on a remote, mountainous Indonesian island, thanks in part to a American ornithologist. The Banggai Crow will be listed now in the latest edition of an influential ornithology handbook. #187; riginal newsA vegetarian spider
Updated: 2009-10-13 19:30:04Each of the world's 40,000 spider species survives by hunting and killing - except, that is, for Bag #187; riginal newsFlocking and Bird Feeders
Updated: 2009-10-13 19:27:54With my migration to the center of the country came an opportunity to put out a bird feeder. I #187; riginal newsGiving cockroaches the slip; University seeks commercial partner to...
Updated: 2009-10-13 19:26:45A breakthrough by scientists at CambridgeUniversitymay terminate the threat of termites, cockroaches and other pests such as ants and locusts - responsible for billions of pounds worth of damage to homes, crops and people's health across the globe each year. #187; riginal newsReport Documents Risks Of Giant Invasive Snakes In The United States
Updated: 2009-10-13 19:26:01Five giant non-native snake species would pose high risks to the health of ecosystems in the United States should they become established here, according to a new U.S. Geological Survey report. #187; riginal newsA tamoxifen inducible knock-in allele for investigation of E2A function
Updated: 2009-10-13 19:25:37Conclusions:The E2AER system provides inducible and reversible regulation of E2A function at the protein level. Many previous studies have utilized over-expression systems to induce E2A function, which are complicated by the toxicity often resulting from high levels of E2A. The E2AER model instead restores E2A activity at an endogenous level and in addition, allows for tight regulation of the timing of induction. These features make our E2AER ex vivo culture system attractive to study both immediate and gradual downstream E2A-mediated events. (Source: BMC Developmental Biology - Latest articles) #187; riginal newsFirst Neotropical Rainforest Was Home Of The Titanoboa -- World's Biggest Snake
Updated: 2009-10-13 15:57:21Researchers working in Colombia's Cerrejón coal mine have unearthed the first megafossil evidence of a neotropical rainforest. Titanoboa, the world's biggest snake, lived in this forest 58 million years ago at temperatures 3-5 C warmer than in rainforests today, indicating that rainforests flourished during warm periods. #187; riginal newsTigers have teeth.
Updated: 2009-10-13 15:08:48For those of you who don’t know, tigers are carnivores. Carnivora is the name of an order of #187; riginal newsRailway engineering
Updated: 2009-10-13 11:25:06Gapless points for safer railways This describes a technology for reducing gaps between rails at points and should help to prevent trains from being derailed. see also: Rush hour train derailed by tunnel points fault (Scotsman) Derailment (Wikipedia)First Spider Known To Science That Feeds Mainly On Plant Food
Updated: 2009-10-12 23:22:23There are approximately 40,000 species of spiders in the world, all of which have been thought to be strict predators that feed on insects or other animals. Now, scientists have found that a small Central American jumping spider has a uniquely different diet: the species Bagheera kiplingi feeds predominantly on plant food. #187; riginal newsART for ART's Sake
Updated: 2009-10-12 23:22:08(Source: Ethology)MedWorm Message: Get the very latest Swine Flu news via the MedWorm Swine Flu RSS news feed - updated hourly from thousands of authoritative health and news sources. #187; riginal newsRare snake discovered in Vernon
Updated: 2009-10-12 23:20:09A resident's sighting of an unfamiliar reptile playing dead in his driveway has led to the first recorded sighting of an Eastern hog-nosed snake in the state. #187; riginal newsScience and Soul: Earthquakes
Updated: 2009-10-12 23:17:49This year’s Nobel Prize in medicine was awarded to three Americans for their discovery of the #187; riginal newsBird moves faster than human sight
Updated: 2009-10-12 23:15:52A while back I came across this YouTube video that features a bird which moves faster than the human #187; riginal newsNo effect of mate novelty on sexual motivation in the freshwater snail Biomphalaria glabrata
Updated: 2009-10-12 23:15:48Conclusions:Our data indicate that mate novelty does affect neither overall sexual motivation nor the choice of mating roles in B. glabrata. Hence, male mate choice via a Coolidge effect appears inexistent in this invertebrate hermaphrodite. We discuss the possible roles of insufficient fitness gains for discriminatory behaviour in populations with frequent mate encounters as well as poor mate discrimination capacities. Our findings lend also no support to the novel prediction that sexual motivation in simultaneous hermaphrodites varies with the mating roles taken during previous copulations, calling for empirical investigation in further hermaphrodite systems. (Source: Frontiers in Zoology) #187; riginal newsLast flutter
Updated: 2009-10-12 02:31:50Eighty years ago, Bhilaru Pumping Station in Mussoorie, a short walk from The Mall Road tourist hubbub, was a hotspot for butterflies. #187; riginal newsFilm: The AntiChrist Dajjal will be a Reptilian Shapeshifter (Random Selection 31)
Updated: 2009-10-12 02:25:15Â Dinosaurs in Freemason cartoons and films tell us, “They’re Back!” or “We #187; riginal newsA tamoxifen inducible knock-in allele for investigation of E2A function
Updated: 2009-10-11 23:00:00Conclusions: The E2AER system provides inducible and reversible regulation of E2A function at the protein level. Many previous studies have utilized over-expression systems to induce E2A function, which are complicated by the toxicity often resulting from high levels of E2A. The E2AER model instead restores E2A activity at an endogenous level and in addition, allows for tight regulation of the timing of induction. These features make our E2AER ex vivo culture system attractive to study both immediate and gradual downstream E2A-mediated events. (Source: BMC Developmental Biology - Latest articles)The Stress Response of the Highly Social African Cichlid Neolamprologus pulcher
Updated: 2009-10-06 15:59:17This study investigates the relationship between social status and circulating plasma cortisol in groups of the cooperatively breeding African cichlid Neolamprologus pulcher. Baseline (resting) levels of cortisol were quantified, as was the cortisol response following an acute stressor. Dominants had the higher cortisol concentrations, and these were not related to their social behavior. Cortisol concentrations correlated (positively) with social behaviors and general activity levels only in subordinate males, arguably the individuals with the least stability in the social group. No status‐dependent differential responses to acute stress were detected, suggesting that the status‐induced chronic stress has little effect on the capacity to mount a full stress response to large‐scale, l...New Jewelry piece
Updated: 2009-10-05 19:44:48
Frog pin made in bronze
Got a little behind my posting with the busy summer season here in the galleRunning Behavior and Its Energy Cost in Mice Selectively Bred for High Voluntary Locomotor Activity
Updated: 2009-10-02 20:37:32Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Locomotion is central to behavior and intrinsic to many fitness‐critical activities (e.g., migration, foraging), and it competes with other life‐history components for energy. However, detailed analyses of how changes in locomotor activity and running behavior affect energy budgets are scarce. We quantified these effects in four replicate lines of house mice that have been selectively bred for high voluntary wheel running (S lines) and in their four nonselected control lines (C lines). We monitored wheel speeds and oxygen consumption for 24–48 h to determine daily energy expenditure (DEE), resting metabolic rate (RMR), locomotor costs, and running behavior (bout characteristics). Daily...Water Supplementation Affects the Behavioral and Physiological Ecology of Gila Monsters (Heloderma suspectum) in the Sonoran Desert
Updated: 2009-10-02 20:23:08Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract In desert species, seasonal peaks in animal activity often correspond with times of higher rainfall. However, the underlying reason for such seasonality can be hard to discern because the rainy season is often associated with shifts in temperature as well as water and food availability. We used a combination of the natural climate pattern of the Sonoran Desert and periodic water supplementation to determine the extent to which water intake influenced both the behavioral ecology and the physiological ecology of a long‐lived desert lizard, the Gila monster (Heloderma suspectum) (Cope 1869). Water‐supplemented lizards had lower plasma osmolality (i.e., were more hydrated) and maintained uri...MedWorm Message: Get the very latest Swine Flu news via the MedWorm Swine Flu RSS news feed - updated hourly from thousands of authoritative health and news sources.Determining Feeding State and Rate of Mass Change in Insectivorous Bats Using Plasma Metabolite Analysis
Updated: 2009-10-02 20:23:02Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Insectivorous bats regularly experience dramatic and sometimes rapid changes in nutrient stores, yet our ability to study these changes has been limited by available techniques. Plasma metabolite analysis has proven effective for studying individual rates of mass change in birds but has not been validated for other taxa. We tested the effectiveness of plasma metabolite analysis by conducting a study with captive big brown bats (Eptesicus fuscus) and little brown bats (Myotis lucifugus) in the field. In the lab, we varied food availability to induce various rates of mass change. As predicted, individual rate of mass change was positively correlated with plasma triglyceride concentration, but ...Supplementary Testosterone Inhibits Paternal Care in a Tropically Breeding Sparrow, Zonotrichia capensis
Updated: 2009-10-02 15:48:03Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract In most male birds that exhibit paternal care, elevation in testosterone above the breeding baseline reduces nestling provisioning, which can be detrimental to offspring survival. Mechanisms that may allow some males to avoid this detrimental effect of elevated testosterone include (1) decreased sensitivity to testosterone’s effects on behavior and (2) uncoupling of testosterone secretion from territorial challenges (thus reducing the number of transient elevations in testosterone above the breeding baseline). Both of these “cost‐avoidance” mechanisms have been documented, but whether selection for these mechanisms is correlated or independent is unknown. We investigated the relation...MedWorm Message: Get the very latest Swine Flu news via the MedWorm Swine Flu RSS news feed - updated hourly from thousands of authoritative health and news sources.Escaping to the Surface: A Phylogenetically Independent Analysis of Hypoxia‐Induced Respiratory Behaviors in Sculpins
Updated: 2009-10-02 15:36:11Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Behavioral responses to progressive hypoxia exposure were assessed in several species of fish from the family Cottidae (sculpins), which are distributed along the near‐shore marine environment and differ in their hypoxia tolerance. The use of aquatic surface respiration (ASR) and aerial emergence as a response to progressive decreases in environmental O2 differed between intertidal and subtidal sculpins. Intertidal sculpins consistently displayed ASR followed by emergence behaviors, while the subtidal species performed these behaviors at low frequency or not at all. There was a significant negative correlation between the O2 thresholds for the onset of ASR and critical O2 tensions (Pcrit, ...The Role of Size in Synchronous Air Breathing of Hoplosternum littorale
Updated: 2009-10-02 15:35:59This study highlights how social interaction can affect air‐breathing behaviors and the importance of considering both behavioral and physiological responses of fish to hypoxia to understand the survival mechanisms they employ. (Source: Physiological and Biochemical Zoology)Unifying Wildfire Models from Ecology and Statistical Physics
Updated: 2009-10-02 15:13:45The American Naturalist, Volume 0, Issue 0, Page E000, Latest Articles. Abstract: Understanding the dynamics of wildfire regimes is crucial for both regional forest management and predicting global interactions between fire regimes and climate. Accordingly, spatially explicit modeling of forest fire ecosystems is a very active field of research, including both generic and highly specific models. There is, however, a second field in which wildfire has served as a metaphor for more than 20 years: statistical physics. So far, there has been only limited interaction between these two fields of wildfire modeling. Here we show that two typical generic wildfire models from ecology are structurally equivalent to the most commonly used model from statistical physics. All three models can be u...A Plant Needs Ants like a Dog Needs Fleas: Myrmelachista schumanni Ants Gall Many Tree Species to Create Housing
Updated: 2009-10-02 15:12:34The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: Hundreds of tropical plant species house ant colonies in specialized chambers called domatia. When, in 1873, Richard Spruce likened plant‐ants to fleas and asserted that domatia are ant‐created galls, he incited a debate that lasted almost a century. Although we now know that domatia are not galls and that most ant‐plant interactions are mutualisms and not parasitisms, we revisit Spruce’s suggestion that ants can gall in light of our observations of the plant‐ant Myrmelachista schumanni, which creates clearings in the Amazonian rain forest called “supay‐chakras,” or “devil’s gardens.” We observed swollen scars on the trunks of nonmyrmecophytic canopy trees surrounding supay‐chakra...Video: Deep sea wildlife of the underwater Sahara mountains
Updated: 2009-10-01 12:30:44
Video footage, shot by the Oceana marine group, of the aquatic wildlife resident on the Sahara seamounts - an underwater mountain range near the Canary IslandsStress and Parental Care in a Wild Teleost Fish: Insights from Exogenous Supraphysiological Cortisol Implants
Updated: 2009-09-30 17:19:23Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Male largemouth bass (Micropterus salmoides) provide sole parental care over a 4–6‐wk period to a single brood, fanning the eggs to keep them oxygenated and free of silt and defending the brood until the offspring develop antipredator tactics. During this period, fish are highly active and have few opportunities for feeding, so this activity is energetically costly. To understand some of the consequences of stress during this challenging period, we injected fish with cortisol suspended in coconut oil to experimentally raise circulating cortisol in parental males for the first week of the parental care period. We compared parental care behavior between cortisol‐treated, sham‐treated (...Macrophysiology: A Conceptual Reunification
Updated: 2009-09-29 15:48:52The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: Widespread recognition of the importance of biological studies at large spatial and temporal scales, particularly in the face of many of the most pressing issues facing humanity, has fueled the argument that there is a need to reinvigorate such studies in physiological ecology through the establishment of a macrophysiology. Following a period when the fields of ecology and physiological ecology had been regarded as largely synonymous, studies of this kind were relatively commonplace in the first half of the twentieth century. However, such large‐scale work subsequently became rather scarce as physiological studies concentrated on the biochemical and molecular mechanisms underlying the capacities and to...Carbon Turnover in Tissues of a Passerine Bird: Allometry, Isotopic Clocks, and Phenotypic Flexibility in Organ Size
Updated: 2009-09-28 22:37:31Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Stable isotopes are an important tool for physiological and behavioral ecologists, although their usefulness depends on a thorough understanding of the dynamics of isotope incorporation into tissue(s) over time. In contrast to hair, claws, and feathers, most animal tissues continuously incorporate carbon (and other elements), and so carbon isotope values may change over time, depending on resource use and tissue‐specific metabolic rates. Here we report the carbon turnover rate for 12 tissues from a passerine bird, the zebra finch (Taeniopygia guttata). We measured average carbon retention time (τ) for 8 d for small intestine; 10–13 d for gizzard, kidney, liver, pancreas, and proventricu...MicroRNAs to Track Evolutionary History for First Time
Updated: 2009-09-27 15:51:27The large group of segmented worms known as annelids, which includes earthworms, leeches and bristle worms, evolved millions of years ago and can be found in every corner of the world. Eventhough annelids are one of the most abundant animal groups on the planet, researchers have struggled to understand how the different species of this biologically diverse group relate to each other in terms of their evolutionary history. Now a team of researchers from Yale University and Dartmouth College has used a groundbreaking method to untangle some of that history........Barcoding endangered sea turtles
Updated: 2009-09-27 15:51:27Conservation geneticists who study sea turtles have a new tool to help track this highly migratory and endangered group of marine animals: DNA barcodes. DNA barcodes are short genetic sequences that efficiently distinguish species from each othereven if the samples from which the DNA is extracted are minute or degraded. Now, a recently published research paper by researchers from the American Museum of Natural History and the University of Canberra, among other organizations, demonstrates that this technology can be applied to all seven sea turtle species and can provide insight into the genetic structure of a widely-dispersed and ancient group of animals........Mechanisms Influencing the Timing and Success of Reproductive Migration in a Capital Breeding Semelparous Fish Species, the Sockeye Salmon
Updated: 2009-09-25 16:47:47Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Two populations of homing sockeye salmon (Oncorhynchus nerka; Adams and Chilko) were intercepted in the marine approaches around the northern and southern ends of Vancouver Island (British Columbia, Canada) en route to a natal river. More than 500 salmon were nonlethally biopsied for blood plasma, gill filament tips, and gross somatic energy (GSE) and were released with either acoustic or radio transmitters. At the time of capture, GSE, body length, and circulating testosterone ([T]) differed between populations, differences that reflected known life‐history variations. Within‐population analyses showed that in Adams sockeye salmon, plasma glucose ([glu]), lactate ([lactate]), and ion co...Generation of neural crest progenitors from human embryonic stem cells.
Updated: 2009-09-23 23:00:00Authors: Chimge NO, Bayarsaihan D The neural crest (NC) is a transient population of multipotent progenitors arising at the lateral edge of the neural plate in vertebrate embryos, which then migrate throughout the body to generate diverse array of tissues such as the peripheral nervous system, skin melanocytes, and craniofacial cartilage, bone and teeth. The transient nature of neural crest stem cells make extremely challenging to study the biology of these important cells. In humans induction and differentiation of embryonic NC occurs very early, within a few weeks of fertilization giving rise to technical and ethical issues surrounding isolation of early embryonic tissues and therefore severely limiting the study of human NC cells. For that reason our current knowledge of the biology...MedWorm Message: Get the very latest Swine Flu news via the MedWorm Swine Flu RSS news feed - updated hourly from thousands of authoritative health and news sources.Mammalian Metabolic Allometry: Do Intraspecific Variation, Phylogeny, and Regression Models Matter?
Updated: 2009-09-23 19:13:01The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: Power scaling relationships between body mass and organismal traits are fundamental to biology. Compilations of mammalian masses and basal metabolic rates date back over a century and are used both to support and to assail the universal quarter‐power scaling invoked by the metabolic theory of ecology. However, the slope of this interspecific allometry is typically estimated without accounting for intraspecific variation in body mass or phylogenetic constraints on metabolism. We returned to the original literature and culled nearly all unique measurements of body mass and basal metabolism for 695 mammal species and (1) phylogenetically corrected the data using the fullest available phylogeny, (2) applie...Why Does Size Matter? A Test of the Benefits of Female Mate Choice in a Teleost Fish Based on Morphological and Physiological Indicators of Male Quality
Updated: 2009-09-21 20:41:12Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract In female mate choice, a female chooses a reproductive partner based on direct or indirect benefits to the female. While sexual selection theory regarding female mate choice is well developed, there are few mechanistic studies of the process by which females evaluate reproductive partners. Using paternal‐care‐providing smallmouth bass (Micropterus dolomieu) as a model, the purpose of this study was to determine the relationship between female mate choice and the morphological and physiological status of chosen males. This was accomplished by locating nests within 1 d of spawning and categorizing brood size (indicator of female mate choice). This was followed by capture of parental males,...DNA from Linnaeus' botanical collections
Updated: 2009-09-21 02:12:55Scientists at Uppsala University has succeeded in extracting long DNA fragments from dried, pressed plant material collected in the 1700s by Linnaeus' apprentice Adam Afzelius. It is hoped that the study, led by Associate Professor Katarina Andreasen, will shed light on whether plants growing today at Linnaeus' Hammarby estate outside Uppsala reflect the species cultivated by Linnaeus himself........Aggressive Behavior and Performance in the Tegu Lizard Tupinambis merianae
Updated: 2009-09-16 19:27:27Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Aggression is an important component of behavior in many animals and may be crucial to providing individuals with a competitive advantage when resources are limited. Although much is known about the effects of catecholamines and hormones on aggression, relatively few studies have examined the effects of physical performance on aggression. Here we use a large, sexually dimorphic teiid lizard to test whether individuals that show high levels of physical performance (bite force) are also more aggressive toward a potential threat (i.e., a human approaching the lizard). Our results show that independent of their sex, larger individuals with higher bite forces were indeed more aggressive. Moreover...Jettisoning Ballast or Fuel? Caudal Autotomy and Locomotory Energetics of the Cape Dwarf Gecko Lygodactylus capensis (Gekkonidae)
Updated: 2009-09-16 19:25:35We examined the effect of tail loss on locomotory costs in the Cape dwarf gecko Lygodactylus capensis (∼0.9 g) using a novel method for collecting data on small lizards, a method previously used for arthropods. We measured CO2 production during 5–10 min of exhaustive exercise (in response to stimulus) and during a 45‐min recovery period. During exercise, we measured speed (for each meter moved) as well as total distance traveled. Contrary to our expectations, tailless geckos overall expended less effort in escape running, moving both slower and for a shorter distance, compared with when they were intact. Tailless geckos also exhibited lower excess CO2 production (CO2 production in excess of normal resting metabolic rate) during exercising. This may be due to reduced metabolically act...Macro‐ and Microgeographic Variation in Metabolism and Hormone Correlates in Big Brown Bats (Eptesicus fuscus)
Updated: 2009-09-16 19:25:06Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract To better understand intraspecific variation in basal metabolic rate (BMR), we examined environmental, physiological, and/or cellular bases for residual variation in BMR in big brown bats, Eptesicus fuscus. We measured BMR and plasma levels of thyroid hormone (T3) and leptin in bats captured in maternity colonies in eastern Massachusetts (MA; northern population) and in Alabama and Georgia (ALGA; southern population) to assess macrogeographic (between‐ or among‐population) and microgeographic (within‐population) variation in those traits. After accounting for effects of body mass, stage of pregnancy, and within‐population variation, bats from the northern population did not differ si...Sexual Selection and the Random Union of Gametes: Testing for a Correlation in Fitness between Mates in Drosophila melanogaster
Updated: 2009-09-16 16:44:44The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: Both males and females vary in fitness. While high‐fitness males typically have greater siring success, it is not clear whether these males sire an equal fraction of offspring from all females or a disproportionately large fraction with high‐fitness females. The latter nonrandom reproductive pattern can arise as the result of sexual selection and creates a positive correlation in fitness between mates. Such a correlation, if it reflects a positive genetic correlation between mates with respect to fitness, increases the efficiency of selection, reducing mutation load and speeding adaptation. While there is evidence from many taxa that assortative mating for fitness may occur, these studies typically f...Announcements
Updated: 2009-09-15 20:30:23The American Naturalist, Volume 174, Issue 4, Page iii-iv, October 2009. (Source: The American Naturalist)How Different Types of Natal Experience Affect Habitat Preference
Updated: 2009-09-14 19:24:42The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: In many animals, exposure to cues in a natal habitat increases disperser preferences for those cues (natal habitat preference induction [NHPI]), but the proximate and ultimate bases for this phenomenon are obscure. We developed a Bayesian model to study how different types of experience in the natal habitat and survival to the age/stage of dispersal interact to affect a disperser’s estimate of the quality of new natal‐type habitats. The model predicts that the types of experience a disperser had before leaving its natal habitat will affect the attractiveness of cues from new natal‐type habitats and that favorable experiences will increase the level of preference for natal‐type habitats more than ...Video: Inside the Natural History Museum's Darwin Centre
Updated: 2009-09-09 00:01:00
A sneak preview of the museum's new cocoon structure, which houses millions of specimens and opens to the public next weekAndy DuckworthLive Where You Thrive: Joint Evolution of Habitat Choice and Local Adaptation Facilitates Specialization and Promotes Diversity
Updated: 2009-09-08 23:20:42The American Naturalist, Volume 0, Issue 0, Page E000, Latest Articles. Abstract: We derive a comprehensive overview of specialization evolution based on analytical results and numerical illustrations. We study the separate and joint evolution of two critical facets of specialization—local adaptation and habitat choice—under different life cycles, modes of density regulation, variance‐covariance structures, and trade‐off strengths. A particular feature of our analysis is the investigation of arbitrary trade‐off functions. We find that local‐adaptation evolution qualitatively changes the outcome of habitat‐choice evolution under a wide range of conditions. In addition, habitat‐choice evolution qualitatively and invariably changes the outcomes of local‐adaptation evol...MedWorm Message: Get the very latest Swine Flu news via the MedWorm Swine Flu RSS news feed - updated hourly from thousands of authoritative health and news sources.Optimization of Resource Allocation Can Explain the Temporal Dynamics and Honesty of Sexual Signals
Updated: 2009-09-08 23:12:08The American Naturalist, Volume 0, Issue 0, Page 000, Latest Articles. Abstract: In species in which males are free to dynamically alter their allocation to sexual signaling over the breeding season, the optimal investment in signaling should depend on both a male’s state and the level of competition he faces at any given time. We developed a dynamic optimization model within a game‐theoretical framework to explore the resulting signaling dynamics at both individual and population levels and tested two key model predictions with empirical data on three‐spined stickleback (Gasterosteus aculeatus) males subjected to dietary manipulation (carotenoid availability): (1) fish in better nutritional condition should be able to maintain their signal for longer over the breeding season, ...Countergradient Variation in Temperature Preference in Populations of Killifish Fundulus heteroclitus
Updated: 2009-09-04 20:35:21Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Behavioral thermoregulation can allow ectotherms to buffer the effects of changes in environmental temperature, and thus an organism’s preferred temperature is thought to be under strong selection. However, this contention has seldom been tested. We used common killifish Fundulus heteroclitus from high‐latitude (northern) and low‐latitude (southern) populations to investigate intraspecific variation in thermal preference and its relationship to habitat temperature. We quantified the preferred temperatures of northern and southern killifish populations acclimated to three temperatures (5°, 15°, and 25°C) to evaluate two alternative hypotheses for the evolution of differences in therm...High‐Temperature Tolerance in Anhydrobiotic Tardigrades Is Limited by Glass Transition
Updated: 2009-09-04 16:38:19In this study, we provide the first evidence of the presence of a glass transition during heating in an anhydrobiotic tardigrade through the use of differential scanning calorimetry. (Source: Physiological and Biochemical Zoology)Thermal Acclimation and Regulation of Metabolism in a Reptile (Crocodylus porosus): The Importance of Transcriptional Mechanisms and Membrane Composition
Updated: 2009-09-04 16:36:29Physiological and Biochemical Zoology, Volume 0, Issue 0, Page 000, Latest Articles. Abstract Energy metabolism is fundamental for animal fitness because it fuels locomotion, growth, and reproduction. Mitochondrial capacities often acclimate to compensate for negative thermodynamic effects. Our aim was to determine the importance of transcriptional regulation and membrane fatty acid composition in modulating oxidative capacities at body temperatures selected in a cold and a warm environment by a reptile (Crocodylus porosus). In the cool environment (mean selected Tb = 21°C), mRNA concentrations of the transcription factor peroxisome proliferator–activated receptor gamma (PPARγ) and its coactivator PPARγ coactivator 1 alpha (PGC‐1α), as well as of the cytochrome c oxidase (COX...In pictures: The week in wildlife
Updated: 2009-09-04 15:36:53
From frolicking bears to fleeing rabbits – the pick of this week's images from the natural world