I am the Online Community Manager at PLoS-ONE (Public Library of Science). My job is to try to motivate you to comment on the papers there. My scientific specialty is chronobiology (circadian rhythms and photoperiodism), with additional interests in comparative physiology, animal behavior and evolution. You can contact me at: Coturnix@gmail.com
David Warlick is a local blogger and educator. We first met at the Podcastercon a couple of years ago, then at several blogger meetups, and finally last January at the second Science Blogging Conference where David moderated a session on Science Education.
Welcome to A Blog Around The Clock. Would you, please, tell my readers a little bit more about yourself? Who are you? What is your background? What is your Real Life job?
I've been an educator for more than 30 years, starting as a middle school social studies, science, and math teacher. Every once in a while, I have to remind myself that when I entered the classroom, desktop computers didn't exist. It constantly astounds me what has been happing around us.
I remained in the classroom for almost 10 years, after which I moved to a central office position supporting instructional technology for a rural school district in NC. I'd been seduced by computers (Radio Shack Model III), and taught myself how to program them, since there wasn't much instructional software available. After that, I moved to the North Carolina State Department of Public Instruction where I wrote and supported curriculum for the state, ran a state-wide bulletin board service (FrEdMail) and finally built the nation's first state department of education web site.
I left the state in 1995, and started consulting, doing business as The Landmark Project. the Internet was still a wilderness, and I wanted to build landmarks for teachers and learners. I maintain a number of web sites which, combined, receive more than a half-million page views a day. I've also had the opportunity to visit educators across the U.S. and Canada, and even in Europe, Asia, and South America.
It seems that I should be near the end of my career. But it certainly doesn't feel like it.
What do you want to do/be when (and if ever) you grow up?
I always wanted to be Johnny Quest's father, Dr. Benton Quest (1960s cartoon series). Wikipedia describes him as: "...'one of the three top scientists in the world,' and apparently something of a Renaissance man; his scientific and technical know-how spans many fields." I wanted to travel the world, have great toys to play with, and solve problems for people. I got part of it, in that I get to travel the world and play with great toys, and there's some adventure, thought it has more to do with navigating exotic airports than defeating evil despots.
But now that all the travel is starting to wear me down, I'm thinking I'd like to settle back to one or two interests, and study/work the hell out of them. Digital photography has always appealed to me. I also enjoy composing music with a computer. I'd also like to find some topic and set up a web site/blog/social network around that topic. No idea, though, what it might be.
You are quite an evangelist for the use of online tools in the classroom. You used to teach with a blackboard and chalk - how and when did you get to embrace the modern tools in education?
My main subject was History. It's what I had studied in college. But I always taught about History from the perspective of technology, focusing in on the invention of the bow & arrow, agriculture, paper, the steam engine and explore how these technologies affected and changed our cultures. The first time I saw a Radio Shack Model I computer operate, I knew, at that moment, that this was one of those technologies that was going to change everything. Here was a machine that you operated by communicating with it. I was thunder-struck. I was seduced.
However, it was sometime later that I started to learn, and am continued to learn that it isn't the fact that we have a machine that we can communicate that makes computers so important. It's that they give us new ways of communicating with each other. This, I've learned as an educator -- not as a technologist.
One of the important concepts you write about is the Flat Classroom. Can you, please, explain it to my readers?
It's simple. According to a recent PEW Internet & American Life study, 64% of American teenagers have produced original digital content and published it to a global audience. How many of their teachers are published authors, artists, musicians, composers, or film makers? From the perspective of our children's information experience, they are more literate than many of their teachers. Our classrooms are flat.
The central question that we should be asking today is, "How do we drive learning if we can no longer rely on gravity?" Where do we get the energy. It's a sobering and threatening idea for most educators. However, I think that once we can get to the other side of this problem, we, teachers and learners, will be much happier. Here are just a few ideas:
* We need to redefine literacy to reflect today's information landscape and not just teach it as skills, but to instill it as habit.
* We, as teachers, need to model learning, not just inflict it. We need to practice new literacy in front of our students.
* What students learn has become less important. The answers are all changing. It as important today to be able to invent answers to brand new questions. What's become more important is how students are learning.
* We need to understand our students information experience and learn to harness the energy that comes from it, to replace the vanishing energy of gravity.
"Please turn off your cell-phones, i-Pods and other electronic devices, kids" - why is this sentence, spoken at the beginning of a class period, wrong? What should a teacher say instead?
This is wrong on so many levels. But principally, we have to recognize, accept, and respect our students out-side-the classroom information experiences. For the first time in history, we are preparing our children for a future we can not clearly describe. So much is changing and so fast. I think that there are clues in our students information experience that we can use to better prepare them for that future.
I recently read about six schools in New York City (where they've banned cell phones) that are giving cell phones to all of their students (2,500 of them), preloaded with 130 minutes of talk time. More minutes are added based on test scores, good behavior, and other activities. The teachers are starting to use text messaging to share homework assignments, remind them of upcoming tests, and other activities. What I'd love to see is text-messaging become a platform for doing homework assignment in collaboration.
I know that this may seem weird to some, but no less (NO LESS) weird than many of the applications we use every day would have seemed 20 years ago, or even 10 years ago.
What is your basic advice to teachers who are not themselves Internet-savvy, yet want to take a plunge and get their students to produce online content, be it blogs, podcasts or videos? How do you explain the pros and cons and the usual traps some teachers fall into?
Be a good teacher, and pay attention to your students information experiences. Your students can teach you a lot about these new tools, and what better way to model yourself as a lifelong learner.
Become 21st century literate. Once you've accomplished that, then you can teach yourself what ever you need to know. Most of the teachers who are doing extraordinary things in their classrooms didn't learn it in a workshop. They learned it by engaging on online conversations with other innovative educators.
When and how did you discover science blogs? What are some of your favourites? Have you discovered any new cool science blogs while at the Conference?
I have to plead the 5th on this one. I do not read any science blogs regularly, though SEED may well take the place of WIRED as my favorite magazine. I'm fascinated by science, all areas of science. Science constantly reminds me of the frontiers we have yet to chart.
Is there anything that happened at this Conference - a session, something someone said or did or wrote - that will change the way you think about science communication, or something that you will take with you to your job, blog-reading and blog-writing?
It thrills me to see that part of learning science is learning how to talk about science. And this is what the Science Bloggers conference is about. It's about the softer side of our explorations, bringing them home, and making them a part of the everyday conversations of the rest of us. I think that, deep down, we all crave frontiers.
It was so nice to see you again at the Conference and thank you for the interview.
According to the referrers pages of my Sitemeter, a lot of you are excited by strange penises, strange penises, strange penises and strange penises (or something like it). So, today we have to move to a different topic, traffic-be-damned, for those without phallic fixations. So, read on (first posted on July 21, 2006)....
I will be going to a scientific conference next week. Believe it or not, this will be the first purely scientific meeting I'll attend since I quit grad school and started blogging (all the others had to do with science communication, blogging, technology, journalism, Internet, publishing...). So, I am thinking....
I remember going to scientific meetings meant going to a nice little Florida resort and spending a couple of days with one's friends and colleagues, isolated from the rest of the world, talking about science 24/7. It is an opportunity to share your latest work and ideas with an inner circle of the field. Seeing one's findings and words plastered all over the Internet is probably not what most people there will expect to happen and some may get dismayed. Has this world changed since the last time I went there? Are the people more aware nowadays that everyone in the audience may be a journalist or a "journalist"? Do they like seeing their ideas disseminated more widely?
So, what is the proper behavior in regard to liveblogging conferences these days? I will see a bunch of talks and posters and will probably find some of them exciting enough to want to write about. I can always approach the speaker afterwards and ask (or warn) or even do a semi-formal interview. But some I just want to quickly liveblog in passing, as things happen. I will bring a notepad, a few good pens and will take good notes, and will have my laptop with me in case I want to liveblog directly into the computer.
The program is publicly available, including all the abstracts. Some posters or slides may even show up online afterwards. There is nothing illegal about blogging about it, but is it against any new unwritten rules?
How about hallway chats? Hotel-room drunken hypothesis-spinning? Beach-side frolicking with crazy geeks who cannot talk about anything but science? Should I warn people that a blogger is in the room?
Serbs voted for closer ties with Europe instead of isolation for the second time in three months in Sunday's snap parliamentary poll, in a stunning turnaround that negated pre- election surveys. A pro-European coalition led by President Boris Tadic won the most votes, claiming 39 per cent of the ballots cast, overtaking the ultra-nationalist Serbian Radical Party as the largest group in parliament, the private election monitoring agency Cesid said.
Even the best of them all, the LDP, won some seats in the Parliament:
Basing its projection on a sample of some 400 key polling stations among 8,600, the traditionally reliable Cesid said another pro- European group, the Liberal-Democratic Party (LDP), won 5.2 per cent of the votes, qualifying for parliament.
A couple of weeks ago when I was in Belgrade, I watched a couple of TV debates and I was impressed at the high level of discourse. All the candidates treated the audience as intelligent and educated and explained their plans in great detail. And they were given plenty of time to do it by the TV moderators whose job was to gently steer the debate and not to grandstand like the BigHeads here do. Even the worst rightwingers explained their proposals in complex sentences and made their plans appear logically coherent. It was up to their opponents from the Left to demonstrate why such proposals, though seemingly attractive, are unworkable in practice or just plain wrong - and it appears that the audience, being intelligent and educated, understood the arguments and voted accordingly.
I wish we could have such a high level of political discourse in the media in the USA....
The key is that complex biochemical processes are taught sequentially, one by one, because that is how we think and process information. Yet, unless there is a need for precise timing (in which case there will be a timer triggering the starts and ends of cellular events), most processes occur all the time, simultaneously, in parallel. How do we teach that?
Investigations continue into the cause of a mysterious illness that has resulted in the deaths of thousands of bats since March 2008. At more than 25 caves and mines in the northeastern U.S., bats exhibiting a condition now referred to as "white-nosed syndrome" have been dying.
Individual birds can adjust their behaviour to take climate change in their stride, according to a study by scientists from the University of Oxford. A study of the great tit (Parus major) population in Wytham Woods, near Oxford, has shown that the birds are now laying their eggs, on average, two weeks earlier than half a century ago. The change in their behaviour enables them to make the most of seasonal food: a bonanza of caterpillars that now also occurs around two weeks earlier due to warmer spring temperatures.
Eco-friendly plant and animal life have been thriving in intensively managed cereal farms alongside increasing crop yields, according to the first study of its kind.
An endangered species of flora or fauna ups the risk of the extinction of the other species in its ecological community. Trophically unique species are more vulnerable for cascading extinction, according to studies of a team of theoretical biologists active at Linköping University and the University of Sheffield.
In the Ebro River delta, the fishing of elver (Anguilla anguilla) leads to the accidental capture of other fish species, with the capture of one ton of elver possibly resulting in the capture of up to 8.2 tons of accompanying species. Researchers from the Institute for Agro-Food Research and Technology (IRTA), who have assessed the effects of this method of fishing and identified the most fragile species, propose improvements in current methodologies.
We have recently covered interesting reproductive adaptations in mammals, birds, insects, flatworms, plants and protists. For the time being (until I lose inspiration) I'll try to leave cephalopod sex to the experts and the pretty flower sex to the chimp crew.
In the meantime, I want to cover another Kingdom - the mysterious world of Fungi. And what follows is not just a cute example of a wonderfully evolved reproductive strategy, and not just a way to couple together my two passions - clocks and sex - but also (at the very end), an opportunity to post some of my own hypotheses online.
Teenagers and young adults across Europe drink and take drugs as part of deliberate sexual strategies. New findings reveal that a third of 16-35 year old males and a quarter of females surveyed are drinking alcohol to increase their chances of sex, while cocaine, ecstasy and cannabis are intentionally used to enhance sexual arousal or prolong sex.
Researchers have shown exactly how the anaesthetic ketamine helps depression with images that show the orbitofrontal cortex - the part of the brain that is overactive in depression - being 'switched off'. Ketamine, an anaesthetic that is popular with doctors on the battlefield and also with vets because it allows a degree of awareness without pain, is a new hope for the treatment of depression - but the minute-by-minute images produced by Professor Bill Deakin and his team show how the drug achieves this in an unexpected way.
Real or perceived threats can trigger the well-known "fight or flight response" in humans and other animals. Adrenaline flows, and the stressed individual's heart pumps faster, the muscles work harder, the brain sharpens and non-essential systems shut down. The whole organism responds in concert in order to survive. At the molecular level, it has been widely assumed that, in single-celled organisms, each cell perceives its environment -- and responds to stress conditions -- individually, each on its own to protect itself. Likewise, it had been thought that cells in multicellular organisms respond the same way, but a new study by scientists at Northwestern University reports otherwise.
Research done by the U.S. Department of the Interior to determine if global warming threatens the polar bear population is so flawed that it cannot be used to justify listing the polar bear as an endangered species, according to a study being published later this year in Interfaces, a journal of the Institute for Operations Research and the Management Sciences.
Since ancient times, locust plagues have been viewed as one of the most spectacular events in nature. In seemingly spontaneous fashion, as many as 10 billion critters can suddenly swarm the air and carpet the ground, blazing destructive paths that bring starvation and economic ruin. What makes them do it? A team of scientists led by Iain Couzin of Princeton University and including colleagues at the University of Oxford and the University of Sydney believes it may finally have an answer to this enduring mystery.
Our governor agrees. At least in the print version of this article which has a somehwat different title: "Easley supports college for aliens". I wonder why they changed it for the Web version - is the editorial position that having green or purple skin disqualifies one from higher education?
Steven M. Davis of Davis Brody Bond Aedas, the museum architects, advocated saving a large part of the wall, as did the engineers, Milan Vatovec, of Simpson Gumpertz & Heger, and Guy Nordenson, of Guy Nordenson & Associates. Others involved with the reconstruction of ground zero were not entirely persuaded that it was worth the effort, cost and potential risk.
Why did I post this? Because Milan Vatovec is a childhood friend of mine (and hockey fans may find his name familiar as he was on the Yugoslav national team for quite a while).
The state Legislature is looking to hire a few good polar bear scientists. The conclusions have already been agreed upon -- researchers just have to fill in the science part.
That's how little Johnny Alaska lawmakers think science works, I guess...
Developing a good impact factor is a nontrivial methodologic undertaking that depends on the intended goal of the rankings. Hence, a scientific discussion about any impact factor requires that its goal is made explicit and its methodology is described in enough detail to make the calculations reproducible. Paradoxically, the methodology of the impact factor that is used to evaluate peer-review journals cannot be fully evaluated in a peer-reviewed journal. As illustrated above, a manuscript describing the Thomson Scientific impact factor would be a hard sell for most journals, and hardly acceptable for the American Journal of Epidemiology, the International Journal of Epidemiology, or Epidemiology.
The same issue also features several interesting responses:
Researchers report that the common weedkiller atrazine may be able to disrupt hormonal signaling in humans. The herbicide is the second-most-applied weedkiller in the United States, with uses from suburban lawns to agricultural production of corn and sorghum.
In recent years, atrazine has been suspected of playing a role in sexual abnormalities in fish, frogs, and other aquatic organisms. The chemical has been banned in Europe, but is still widely used in the U.S. Now, writing in the journal PLOS One, researchers report that the chemical appears to affect two different genes in human placental cells. We'll talk with one of the authors of the study about the work and what it means.
In humans, faces are an important source of social information. One property of faces that is rapidly noticed is attractiveness. Research has highlighted symmetry and sexual dimorphism (how masculine or feminine a face is) as important variables that determine a face's attractiveness.
What if hydrology is more important for predicting biodiversity than biology? New research challenges current thinking about biodiversity and opens up new avenues for predicting how climate change or human activity may affect biodiversity patterns.
Researchers from the Wildlife Conservation Society (WCS) found that the black bears that become habituated to human food and garbage may not be learning these behaviors exclusively from their mothers, as widely assumed. Bears that steal human food sources are just as likely to form these habits on their own or pick them up from unrelated, "bad influence" bears.
Whether a young man's mother earned a college degree and whether she worked outside the home while he was growing up seems to have an effect years later when he considers his ideal wife, according to a study by University of Iowa sociologist Christine Whelan.
One of the major scientific questions about the brain is how it can translate the simple intent to perform an action--say, reach for a glass--into the dynamic, coordinated symphony of muscle movements required for that action. The neural instructions for such actions originate in the brain's primary motor cortex, and the puzzle has been whether the neurons in this region encode the details of individual muscle activities or the high-level commands that govern kinetics--the direction and velocity of desired movements.
The developing nervous system makes far more nerve cells than are needed to ensure target organs and tissues are properly connected to the nervous system. As nerves connect to target organs, they somehow compete with each other resulting in some living and some dying. Now, using a combination of computer modeling and molecular biology, neuroscientists at Johns Hopkins have discovered how the target tissue helps newly connected peripheral nerve cells strengthen their connections and kill neighboring nerves. The study was published in the April 18th issue of Science.
The first analysis of the genome sequence of the duck-billed platypus was published today by an international team of scientists, revealing clues about how genomes were organized during the early evolution of mammals. The research was supported in part by the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health (NIH).
Fans of TV nature shows will remember that the duck-billed platypus, native to Australia, is one of the few mammals that lay eggs. However, platypus peculiarity does not end there. For example, these odd animals boast what looks like a duck's bill, which houses an electrosensory system used when foraging for food underwater, and a thick fur coat to adapt to the icy waters in which it resides. Males also possess hind leg spurs that can deliver venom powerful enough to wound territorial competitors during mating season, or cause excruciating pain in other mammals, including humans.
"At first glance, the platypus appears as if it was the result of an evolutionary accident. But as weird as this animal looks, its genome sequence is priceless for understanding how fundamental mammalian biological processes have evolved," said Francis S. Collins, M.D., Ph.D., director of NHGRI. "Comparisons of the platypus genome to those of other mammals will provide new insights into the history, structure and function of our own genome."
In a paper published in today's issue of the journal Nature, researchers analyzed a high-quality draft genome sequence of Glennie, a female platypus from Australia. The consortium included scientists from the United States, Australia, England, Germany, Israel, Japan, New Zealand and Spain. Sequencing of the platypus genome was led by the Genome Sequencing Center at Washington University School of Medicine in St. Louis, a part of NHGRI's Large-Scale Sequencing Research Network.
Once the sequence was produced, researchers began comparing the genome of the platypus, whose ancestors split from the rest of mammalian lineage some 166 million years ago, with the well-characterized genomes of the human, mouse, dog, opossum and chicken, as well as the draft genome sequence of the green anole lizard. The chicken genome was chosen because it is descended from the ancestral group of egg-laying animals, including extinct reptiles, who passed on much of their DNA to animals like the platypus. Scientists were particularly interested in finding features within the platypus genome that could explain the odd mix of characteristics seen in the platypus: those that were more like reptiles, birds and mammals.
The team found that the platypus genome contains about the same number of protein-coding genes as other mammals -- approximately 18,500. The platypus also shares more than 80 percent of its genes with other mammals whose genomes have been sequenced. Next, researchers combed the platypus genome looking for genetic evidence of sequences unique to platypuses that have been lost from mammalian genomes. Scientists were also eager to find out what characteristics of the platypus were linked at the DNA level to reptiles or mammals.
"The mix of reptilian, mammalian and unique characteristics of the platypus genome provides many clues to the function and evolution of all mammalian genomes," said Richard K. Wilson, Ph.D., director of Washington University School of Medicine's Genome Sequencing Center and the paper's senior author. "Now, we'll be able to pinpoint genes that have been conserved throughout evolution, as well as those that have been lost or gained."
The challenge from skullsinthestars is up - pick up a very old, classic science paper and write a blog post about it. Put it in a proper historical, theoretical, methodological and philosophical context. You can always go back to blogging about the latest research or latest creationist idiocy tomorrow.
My daughter collects snowglobes. Or, to be precise, we collect snowglobes for her when we travel. She has a few from New York City, one from San Francisco, one from Murtle Beach, one from Milwaukee. I badly messed up when I went to Boston last year and did not get one. Last year, the TSA made a rule that snowglobes cannot be in the carry-on luggage (and I prefer to travel light and not check in any bags), but the lax security at Milwaukee airport let me smuggle one in.
Now, traveling around Europe provided me with the opportunity to greatly add to her collection: snowglobes from London, Cambridge, Cromer, Trieste, Belgrade and Berlin. Carrying them on European airlines was easy, but I checked in the suitcase on the last flight back to the USA:
Open Access Directory (OAD) is a wiki that contains all the information one may need and want in regard to Open Access Publishing, from jobs to research questions. You should bookmark it and check it out regularly.
Humanities bloggers have been way ahead of science bloggers in regards to posting their own work (including ideas, hypotheses and rough drafts) online, yet official humanities publishing has lagged behind natural sciences and medicine when it comes to adopting Open Access, so this is a very positive move on their part.
There are 56 new articles published in PLoS ONE this week and it was hard to make the picks as this seems to be a very, very good week with lots of cool papers. Here are some of the highlights - please post ratings, notes and comments on the papers, write blog posts and send trackbacks:
The Janzen-Connell model states that plant-specific natural enemies may have a disproportionately large negative effect on progeny close to maternal trees. The majority of experimental and theoretical studies addressing the Janzen-Connell model have explored how it can explain existing patterns of species diversity in tropical mainland areas. Very few studies have investigated how the model's predictions apply to isolated oceanic islands, or to the conservation management of endangered plants. Here, we provide the first experimental investigation of the predictions of the Janzen-Connell model on an oceanic island, in a conservation context. In addition, we experimentally evaluate the use of ecological analogue animals to resurrect the functional component of extinct frugivores that could have dispersed seeds away from maternal trees. In Mauritius, we investigated seed germination and seedling survival patterns of the critically endangered endemic plant Syzygium mamillatum (Myrtaceae) in relation to proximity to maternal trees. We found strong negative effects of proximity to maternal trees on growth and survival of seedlings. We successfully used giant Aldabran tortoises as ecological analogues for extinct Mauritian frugivores. Effects of gut-passage were negative at the seed germination stage, but seedlings from gut-passed seeds grew taller, had more leaves, and suffered less damage from natural enemies than any of the other seedlings. We provide the first experimental evidence of a distance-dependent Janzen-Connell effect on an oceanic island. Our results potentially have serious implications for the conservation management of rare plant species on oceanic islands, which harbour a disproportionately large fraction of the world's endemic and endangered plants. Furthermore, in contrast to recent controversy about the use of non-indigenous extant megafauna for re-wilding projects in North America and elsewhere, we argue that Mauritius and other oceanic islands are ideal study systems in which to empirically explore the use of ecological analogue species in restoration ecology.
Phylogenetic mitochondrial DNA haplogroups are highly partitioned across global geographic regions. A unique exception is the X haplogroup, which has a widespread global distribution without major regions of distinct localization. We have examined mitochondrial DNA sequence variation together with Y-chromosome-based haplogroup structure among the Druze, a religious minority with a unique socio-demographic history residing in the Near East. We observed a striking overall pattern of heterogeneous parental origins, consistent with Druze oral tradition, together with both a high frequency and a high diversity of the mitochondrial DNA (mtDNA) X haplogroup within a confined regional subpopulation. Furthermore demographic modeling indicated low migration rates with nearby populations. These findings were enabled through the use of a paternal kindred based sampling approach, and suggest that the Galilee Druze represent a population isolate, and that the combination of a high frequency and diversity of the mtDNA X haplogroup signifies a phylogenetic refugium, providing a sample snapshot of the genetic landscape of the Near East prior to the modern age.
Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt). We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of Bt cotton, maize and potato on the abundance and interactions of arthropod non-target functional guilds. We compared the abundance of predators, parasitoids, omnivores, detritivores and herbivores under scenarios in which neither, only the non-Bt crops, or both Bt and non-Bt crops received insecticide treatments. Predators were less abundant in Bt cotton compared to unsprayed non-Bt controls. As expected, fewer specialist parasitoids of the target pest occurred in Bt maize fields compared to unsprayed non-Bt controls, but no significant reduction was detected for other parasitoids. Numbers of predators and herbivores were higher in Bt crops compared to sprayed non-Bt controls, and type of insecticide influenced the magnitude of the difference. Omnivores and detritivores were more abundant in insecticide-treated controls and for the latter guild this was associated with reductions of their predators in sprayed non-Bt maize. No differences in abundance were found when both Bt and non-Bt crops were sprayed. Predator-to-prey ratios were unchanged by either Bt crops or the use of insecticides; ratios were higher in Bt maize relative to the sprayed non-Bt control. Overall, we find no uniform effects of Bt cotton, maize and potato on the functional guilds of non-target arthropods. Use of and type of insecticides influenced the magnitude and direction of effects; insecticde effects were much larger than those of Bt crops. These meta-analyses underscore the importance of using controls not only to isolate the effects of a Bt crop per se but also to reflect the replacement of existing agricultural practices. Results will provide researchers with information to design more robust experiments and will inform the decisions of diverse stakeholders regarding the safety of transgenic insecticidal crops.
Many predators display two foraging modes, an ambush strategy and a cruising mode. These foraging strategies have been classically studied in energetic, biomechanical and ecological terms, without considering the role of signals produced by predators and perceived by prey. Wolf spiders are a typical example; they hunt in leaf litter either using an ambush strategy or by moving at high speed, taking over unwary prey. Air flow upstream of running spiders is a source of information for escaping prey, such as crickets and cockroaches. However, air displacement by running arthropods has not been previously examined. Here we show, using digital particle image velocimetry, that running spiders are highly conspicuous aerodynamically, due to substantial air displacement detectable up to several centimetres in front of them. This study explains the bimodal distribution of spider's foraging modes in terms of sensory ecology and is consistent with the escape distances and speeds of cricket prey. These findings may be relevant to the large and diverse array of arthropod prey-predator interactions in leaf litter.
Little is known about the effect of physical exercise on influenza-associated mortality. We collected information about exercise habits and other lifestyles, and socioeconomic and demographic status, the underlying cause of death of 24,656 adults (21% aged 30-64, 79% aged 65 or above) who died in 1998 in Hong Kong, and the weekly proportion of specimens positive for influenza A (H3N1 and H1N1) and B isolations during the same period. We assessed the excess risks (ER) of influenza-associated mortality due to all-natural causes, cardiovascular diseases, or respiratory disease among different levels of exercise: never/seldom (less than once per month), low/moderate (once per month to three times per week), and frequent (four times or more per week) by Poisson regression. We also assessed the differences in ER between exercise groups by case-only logistic regression. For all the mortality outcomes under study in relation to each 10% increase in weekly proportion of specimens positive for influenza A+B, never/seldom exercise (as reference) was associated with 5.8% to 8.5% excess risks (ER) of mortality (P<0.0001), while low/moderate exercise was associated with ER which were 4.2% to 6.4% lower than those of the reference (P<0.001 for all-natural causes; P = 0.001 for cardiovascular; and P = 0.07 for respiratory mortality). Frequent exercise was not different from the reference (change in ER −0.8% to 1.7%, P = 0.30 to 0.73). When compared with never or seldom exercise, exercising at low to moderate frequency is beneficial with lower influenza-associated mortality.
Many animals both display and assess multiple signals. Two prominently studied traits are symmetry and sexual dimorphism, which, for many animals, are proposed cues to heritable fitness benefits. These trait
One of the important concepts you write about is the Flat Classroom. Can you, please, explain it to my readers?
