World Association of Young Scientists

Shark attacks are events of speed and violence. When they have locked on to a prey item sharks seem to come out of nowhere, and though they can be quite gentle with their jaws (as on occasions when they are unsure about whether something is food or not) their ranks of serrated teeth can inflict a devastating amount of damage. They are not the cruel, vicious, or bloodthirsty villains they have often been portrayed as, but instead are exquisitely-adapted predators which rely on their ability to catch and consume a variety of prey. And, just as it is among present day sharks, so it was among their prehistoric relatives.

Between 19 and 8 million years ago Maryland's Calvert Cliffs were covered by the ocean. Those shallow waters were inhabited by at least fifteen different genera of sharks, and their teeth (typically all that is left of them) are scattered everywhere along the beaches. Indeed, they are abundant enough that paleontologists Christy Visaggi and Stephen Godfrey recently cataloged of 26,000 of them to determine what kinds of sharks lived off the shores of ancient Maryland and in what numbers.

Their findings, printed in the Journal of Vertebrate Paleontology, reveal that this habitat was home to a mix of both living and extinct shark genera. There were fossils from Hemipristis (snaggletooth sharks), Galeocerdo (tiger sharks), Carcharias (sand tiger sharks), Carcharhinus (a subset of requiem sharks), and Isurus (mako sharks) in addition to the famous superpredator Carcharocles megalodon, most of which came from the time interval between 19 and 14 million years ago. (Teeth from many other genera, such as those related to whale sharks and great white sharks, were also found, but were so rare that they did not constitute a significantly significant sample.) While not exactly the same as their living relatives, these Miocene sharks would have looked very familiar to us, and clearly the area that would become the Calvert Cliffs was a very productive marine ecosystem which could support such a wide array of predators. Not surprisingly, there was plenty of prey in the water, too. Although not explicitly considered in their study, Visaggi and Godfrey noted that fish, sea turtles, crocodiles, birds, seals, sea cows, and numerous whale species all lived in the same place, and every now and then a specimen of one of these animals is found showing evidence of shark attack.

Read the rest of this post... |

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Collective Imagination

See original: Unique Fossils Record the Dining Habits of Ancient Sharks [Laelaps]

Ten years ago, President Clinton laid the foundation stone of the current global Nanotechnology Initiative.  In a speech given at at Caltech, he announced the formation of the US National Nanotechnology Initiative, and set a chain of events in motion that has led to economies and businesses around the world investing in the technology of [...]

See original: The UK Nanotechnologies Strategy – disappointing

mrgunn: @jmburroughs You might also want to take a look at Mendeley if the in-browser thing doesn't work for you: http://bit.ly/181tmi

See original: @jmburroughs You might also want to take a look at Mendeley if the in-browser thing doesn't work for you: http://bit.ly/181tmi

mrgunn: @doc_becca So close! A couple more hundredths and you'd be inside the magic 95% ;-)

See original: @doc_becca So close! A couple more hundredths and you'd be inside the magic 95% ;-)

One night of passion and you're filled with a lifetime full of sperm with no need to ever mate again. As sex lives go, it doesn't sound very appealing, but it's what many ants, bees, wasps and termites experience. The queens of these social insects mate in a single "nuptial flight" that lasts for a few hours or days. They store the sperm from their suitors and use it to slowly fertilise their eggs over the rest of their lives. Males have this one and only shot at joining the Mile High Club and they compete fiercely for their chance to inseminate the queen. But even for the victors, the war isn't over. Inside the queen's body, their sperm continue the battle.

If the queen mates with several males during her maiden flight, the sperm of each individual find themselves swimming among competitors, and that can't be tolerated. Susanne den Boer from the University of Copenhagen has found that these insects have evolved seminal fluids that can incapacitate the sperm of rivals while leaving their own guys unharmed. And in some species, like leafcutter ants, the queen steps into the fray herself, secreting chemicals that pacify the warring sperm and ease their competition.

The amazing thing about this chemical warfare is that it has evolved independently several times. Social insects evolved from ancestors that observed strictly monogamous relationships. Even now, the queens from many species mate with just one male during their entire lives. With just one set of sperm in their bodies, they have no problem with sperm conflict. The trouble starts when species start mating with several males during their nuptial flights, as honeybees, social wasps, leafcutter ants, army ants, and others do today. 

Read the rest of this post... |

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Collective Imagination

See original: Sperm war - the sperm of ants and bees do battle inside the queens [Not Exactly Rocket Science]

sandygautam: many thanks! re: http://ff.im/hJQwI

See original: many thanks! re: http://ff.im/hJQwI

mrgunn: RT @BoraZ: The ultimate Ivory Tower denizen advises scientists to get out of Ivory Tower http://bit.ly/djJN19 Irony. It burns.

See original: RT @BoraZ: The ultimate Ivory Tower denizen advises scientists to get out of Ivory Tower http://bit.ly/djJN19 Irony. It burns.

17/2/2010 BBC Richard Black Some interesting perspectives on communication, information and climate change emerge this week from Africa and the UK.A survey for the BBC World Service Trust (the corporation’s international charitable arm) shows that although many Africans are noticing progressive changes to their weather, they’re tending to ascribe those changes to agents above and outside [...]

See original: Climate change adverts far from divine

The SPARC guide, by Greg Tananbaum, is not an advocacy document promoting the launch of Open-access Funds. Rather, we aim to help institutions that are curious to better understand why funds are being launched, the considerations and decisions involved in their creation, and how existing funds are being managed. Should you choose to move forward with creating an open-access fund, this guide will help you to do so with your best foot forward.

See original: Campus-based open-access Publishing Funds: A Practical Guide to Design and Implementation

I try not to travel in the spring. Instead of the stale air of the airplane, I try to get out to the mountains, the beach, the garden or to the nearby foothills.

Last weekend my daughter and I (who is 8 years old today), went for a walk. I thought she was strong enough to do the 5 mile hike in the Stebbins Cold Canyon Preserve so off we happily went. As we started up the VERY steep hill, her trust began to dissipate. Then the inevitable "I want to go home".

I definitely did not want to go home. More than that, I did not want her to want to go home.

Read the rest of this post... |

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Collective Imagination

See original: Spring in California [Tomorrow's Table]

I have an article at Slate magazine today that ties together and elaborates on some of the themes explored at this blog over the past several weeks. Below is the lede to the full article. No doubt, the article will generate a good amount of discussion which I will highlight in follow up posts. I will also highlight specific comments made over at Slate.

Chill Out: Climate scientists are getting a little too angry for their own good.

By Matthew C. Nisbet

As Congress continues to struggle its way toward new energy legislation, climate scientists are getting a little hot. A series of major attacks from the global-warming skeptics--including last year's Climategate affair and unfair accusations stemming from the subsequent discovery of errors in the latest IPCC report--have left those in the research community understandably angry. Having spent eight years calling attention to the politicization of climate science by the Bush administration, they now find themselves on the other end of the same allegations. Whatever raw emotions this reversal might produce were on display a couple of weeks ago in yet another series of leaked e-mails: This time, members of the prestigious National Academies complained to one another about the "neo-McCarthyism" of the climate skeptics and lamented that "science is getting creamed with no effective response." One researcher called for "a relentless rain of science and scientific dialog on the incredible, destructive demagoguery." Another participant urged an "aggressively partisan approach."

The latest batch of e-mails reflects a bunker mentality among climate scientists, forged during the Bush administration and reinforced by the recent attacks on their credibility. Despite the promise of an Obama presidency, many now see themselves losing a "war" against "anti-science" forces allied with energy companies and the Republican Party. Meanwhile, scientists have been urged by liberal strategists and commentators to "fight back"--by forming their own political action committees and openly supporting "pro-science" candidates, among other things.

But urgent calls to escalate the war against climate skeptics may lead scientists and their organizations into a dangerous trap, fueling further political disagreement while risking public trust in science. A major transformation is needed in how scientists and their organizations engage the public and policymakers. The new direction is not to become more political and confrontational on the national stage, but to seek opportunities for greater public interaction, dialogue, and partnerships in communities across the country.

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Collective Imagination

See original: At Slate, A Need for Diplomacy in the Climate Wars [Framing Science]

When Google started "suggesting" the most popular search phrases below its query box, I was creeped out. Especially when I saw what it suggests for "is Obama". Yes, I was happier when I didn't know what other people were typing into Google.

However, the folks at HINT.fm took the opposite approach: they created an interface that invites you to explore the most popular search phrases for any given starting words. I took it for a spin to see what the American public is asking about you-know-who: scientists. (You totally thought I was going to say Palin, didn't you?)

click image for a larger and more readable pop-up.

While this is hardly a methodologically rigorous analysis (and we don't get hard numbers), the results are interesting. First, it appears an ever-optimistic sliver of our population hopes that we are, in fact, in search of a cure for herpes. Talk about eternal questions! Second, among the queries starting "do scientists," the questions about scientific consensus on global warming far outnumber the one question about evolution. This surprised me a little - as a biologist who has dealt with anti-evolution sentiment in my lectures, evolution will always be the "big" anti-science issue. But most people already know where scientists come down on evolution, so why ask? Global warming, on the other hand, is perceived by the public to be in a state of more active and urgent debate.

Another notable thing is that most of the "do scientist" queries continue "do scientists believe in. . . " when that faith-centric wording would probably not be used by a scientist to refer to global warming, evolution, aliens or ghosts (although "believe in God" or "believe in life after death" are probably okay). And what's with the "2012" question? It turns out a bunch of people are predicting the world will end in 2012. I had absolutely no idea until I did this little exercise - it really has put me in touch with the zeitgeist!

Read the rest of this post... |

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Collective Imagination

See original: Top Google queries about scientists: should we be surprised? [bioephemera]

sandygautam: please send to sandygautam@yahoo.com re: http://ff.im/hJQwI

See original: please send to sandygautam@yahoo.com re: http://ff.im/hJQwI

sandygautam: Looking for Two Views of Brain function, doi:10.1016/j.tics.2010.01.008... http://ff.im/-hJQwI

See original: Looking for Two Views of Brain function, doi:10.1016/j.tics.2010.01.008... http://ff.im/-hJQwI

This post has been generated by Page2RSS

See original: at gamma-ray energies remain otherwise unidentified, not associated