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There may be a way to activate those genes without caloric restriction... someone noted that in the original experiments with mice, calories were restricted by only feeding the mice every other day. Someone decided to see what effect the timing would have if the mice were allowed to eat the same amount as the control group, but half as often: http://www.pnas.org/cgi/content/full/100/10/6216

I fail to see what makes this article front page material. For starters CREB is a transcription factor that has implications in much more functions that neuronal ones (its just researched a lot in that context). It responds to cAMP concentrations which is a widely used secondary messenger in cellular information flow. Its present in many organisms ranging from slugs to humans.

A novel way of finding genes that might be regulated by CREB, the article doesnt discribe the exact algoritm but this isnt exactly new either: http://en.wikipedia.org/wiki/Sequence_alignment#Mo tif_finding

Screening the genome for possible locations of these CREB responsive genes, is that new? Nope not exactly: http://www.pnas.org/cgi/content/abstract/102/12/44 59
"Genome-wide analysis of cAMP-response element binding protein occupancy, phosphorylation, and target gene activation in human tissues" (received for review January 14, 2005)

Im not saying that CREB isnt involved in long term memory (which it is), but this approach seems an inappropriate way to tackle the problem, I can see the false positives piling up since CREB is implemented in general cellular survival pathways and a whole plethora of other systems. So it certainly isnt THE answer to brain function. Id really like to see that people would finaly abandon the outdated 1 to 1 gene phenotype/function view that sparks many of those populistic articles

If you really want to conceptually tackle the problem of how brain and memory works, youd better take a look at epigenetics: http://en.wikipedia.org/wiki/Epigenetics

• Molecular hydrogen (H2) physically sticking to a porous storage medium, such as a metal organic framework, without chemically reacting.
• Chemically storing atomic hydrogen in a compounds, such as metal hydrides, where it can reversibly react to form H2.

The reason the weight percent numbers seem small is that H2 has a molecular weight of ~2 AMU and any material with the capacity to adsorb lots of hydrogen or store it chemically is going to be made of much heavier atoms. In this way, mass percentage is deceiving but it is the most common measure of storage capacity. My wild guess is that the 6.5% cutoff is in the ballpark of the energy output to mass ratio of gasoline. Luckily, neither fuel requires the automobile to haul around all the oxygen necessary to for the reactions.

If people aren't happy with single digit weight percentages, they could suggest using a heavier hydrogen isotopes to double or triple the numbers!

It's highly unsurprising that attention can be modulated by things we don't perceive. For a psychophysics study with an unbeatable title that supports the conclusion: " A gender- and sexual orientation-dependent spatial attentional effect of invisible images" http://www.pnas.org/cgi/content/abstract/060567810 3v1

As a neuroscientist

Because all of that is explained by their model, as outlined in their first and second articles.

In short, it goes like this: by dissolving in the membrane, anesthetics lower the melting point of the membrane, thereby affecting its sound propagation properties. The lowering of the melting-point can be reversed by applying pressure, lowering temperature, or by lowering pH. So by assuming that the nerve impulse is transmitted by a soliton in the membrane, everything is explained.

Looks like it actually made PNAS about a year and a half ago. http://www.pnas.org/cgi/reprint/102/28/9790

Either way, the summary and the linked article look to be way off base.

BTW, IAANS (I am a neuroscientist). Here is another link to their earlier research on this. While PNAS is certainly a reputable journal, I made some interesting observations while reading their paper:

(1) It's very physics- and modeling-heavy. While I don't like to generalize, my impression has always been that physicists are not very good biologists. I've been to many a "cross-disciplinary" seminars where physicists try to model biological processes, and inevitably they make very little biological sense.

(2) They cite mostly old papers from the literature (1960s) that point out deficiencies in the Hudgkin-Huxley model (although it's true that the HH model of action potential propagation may have become dogmatic).

(3) It was published via track I in PNAS, wherein a Member of the National Academy of Sciences can directly accept the paper for publication, bypassing peer review. The purpose of this mechanism is so that controversial works have a chance to be published; historically, it has been used to dole out favors and/or to publish crackpot theories.

Ultimately, while what they are proposing is not as crazy as TFA makes it out to be, the paper sounds to me that they are trying to make a mountain out of a molehill. Neuroscientists today have a very detailed understanding of how axonal neurotransmission works. The authors claim that the solitons (sound waves) in their model explain how nerve propagation in myelinated axons can be much faster than in equivalent non-myelinated axons, but again, neuroscientists are fairly sure they understand myelination in the context of the HH model. Even if axons go through soliton mediated pulses on the membrane that are in phase with action potentials (which is what they claim to observe), I seriously doubt that it has any physiological relevance, since just about everything neurons can do can be explained by ion flux through channels.

All the reasons made for the continuation of the status quo are just excuses that benefit only the owners of the journals. One justification for the high cost of the journals is printing. But who really needs to go to the library to read the Journal of Biological Chemistry or the Proceedings of the National Academy of Sciences in their dead tree format anyway? If a library really needs a paper copy, perhaps they can just send out the PDFs to a third-party printer to print and bind it. I don't think we need Elsevier to do the printing and distribution. The internet already performs the distribution process very efficiently. So the traditional for-profit scientific journal publishers need to go the way of blacksmiths and scabbard makers. As for the world's premier science journal, Nature, perhaps Google or the Gates Foundation or Warren Buffet can just ask them what is their projected profit from the sales of subscriptions and archived articles for the next 10 years, pay them twice that amount, secure the copyright to past articles and future publication the journal and hire the entire editorial board. I don't think it would cost a lot. Now that would be a service to mankind.

I have no idea when you checked, but PNAS offers a number of tracks for submission, all of which are refereed (though cynics might think that some are refereed more stringently than others). The information is displayed for all to see at their information for authors page.

Crows, it appears , will also use tools to get at grubs they otherwise wouldn't be able to kill and eat. Some critters are smart that way. There are also now observed cases of mother dolphins passing along tool-using culture in food-gathering.

Here's a link to the abstract from the original paper:

http://www.pnas.org/cgi/content/abstract/104/4/133 1

The question of whether the ocean is a source or sink of carbon is an important one for carbon balance, and to be honest was the source of a lot of my discomfort several years ago with the conclusion that warming is primarily anthropogenic. However, the magnitude of the flux either way had already been constrained to indicate that there was no way that ocean could be providing enough carbon to account for the increases seen in the atmosphere. And:

http://www.pnas.org/cgi/content/full/94/16/8308

clear observations of the oceanic uptake of carbon have been around for a decade now. So much so, that there's substantial concern about collapse of populations of coral and certain phytoplankton.

That's my principal problem with the "skeptics". The questions that "skeptics" ask, have either been asked and answered (as in oceanic carbon signal or changes in solar irradiance), or they represent unpromising avenues of inquiry motivated not by overall interest in advancing the status of the field, but in blocking progress towards more certainty and preserving doubt.

What you see from Pat Michaels is not healthy scientific skepticism anymore, it is paid disinformation. What you see from Richard Lindzen and William Gray is probably more cranky personal contrarianiness than shilling, but it is also not oriented towards helping science move forward and resolve genuine doubts.

There are still real problems with global climate models, which is why there's not much consensus on what warming will happen where, when, or even the magnitude of the warming by 2100 (2C to 10C is a pretty big range!). But there is no doubt that human activities are an important contributor to climate change.

Except the oceans are currently a massive CO2 sink, not a net CO2 source.

Two decades of ocean CO2 sink and variability (abstract)
The Acid Ocean - the Other Problem with CO2 Emission
Direct observation of the oceanic CO2 increase revisited

There may have been individual years warmer than 2006 in the Medieval Warm Period, however there is no record accurate enough to say. What can be said was that the Medieval Warm period was not as warm, as a whole, as the climate has been in the last 50 years.

Of course, "ever" is a ridiculous word to use; temperatures were much warmer back in the Cretaceous. The present climate, however, is overall probably warmer than it has been in about 12,000 years (at the Holocene maximum).

Yeah, I was suspicious of it then, too.

The taxi drivers have a 20% reduction in anterior hippocampus. And
a 7-8% increase in posterior hippocampus.

Therefore the brain grows from experience!
http://www.pnas.org/cgi/content/full/97/8/4398/F2

Then they went on to show a correlation with time as a taxi driver,
but it was only significant if they removed one outlier, a process
that COULD NOT POSSIBLY HAVE BEEN important to their statistical
finding.
http://www.pnas.org/cgi/content/full/97/8/4398

That part of the brain has neurons that are selectively active
for the spatial position of the body in rats and Rhesus monkeys. So
it would not be surprising to find it responded to taxi driving
experience. But the surprising thing is the much larger reduction in
anterior hippocampal volume is being ignored...

I am totally in favor of our new GPS automatic map making
overlords!

Yeah, I was suspicious of it then, too.

The taxi drivers have a 20% reduction in anterior hippocampus. And
a 7-8% increase in posterior hippocampus.

Therefore the brain grows from experience!
http://www.pnas.org/cgi/content/full/97/8/4398/F2

Then they went on to show a correlation with time as a taxi driver,
but it was only significant if they removed one outlier, a process
that COULD NOT POSSIBLY HAVE BEEN important to their statistical
finding.
http://www.pnas.org/cgi/content/full/97/8/4398

That part of the brain has neurons that are selectively active
for the spatial position of the body in rats and Rhesus monkeys. So
it would not be surprising to find it responded to taxi driving
experience. But the surprising thing is the much larger reduction in
anterior hippocampal volume is being ignored...

I am totally in favor of our new GPS automatic map making
overlords!

Studies were published in the year 2000. Why is this now getting attention? Actually, come to think of it, I think it got attention back then too.

I work at a major medical school in the U.S., and so the first thing I did when I read the linked article (I know, I know, GASP!) was find out what journal this was published in -- we have online subscriptions to hundreds of journals, so surely I could go to the primary source. PNAS considers this important enough that it has the article tagged as "open access" -- free for all to read.

Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific -- Worthy et al., 10.1073/pnas.0605684103 -- Proceedings of the National Academy of Sciences

The abstract is standard HTML, but the full article is in PDF format (link to the full article PDF).

Citation:

Worthy, T. H., A. J. Tennyson, M. Archer, A. M. Musser, S. J. Hand, C. Jones, B. J. Douglas, J. A. McNamara and R. M. Beck (2006). Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific. Proc Natl Acad Sci U S A.

(no volume or page numbers as this article has not yet been published in print).

I work at a major medical school in the U.S., and so the first thing I did when I read the linked article (I know, I know, GASP!) was find out what journal this was published in -- we have online subscriptions to hundreds of journals, so surely I could go to the primary source. PNAS considers this important enough that it has the article tagged as "open access" -- free for all to read.

Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific -- Worthy et al., 10.1073/pnas.0605684103 -- Proceedings of the National Academy of Sciences

The abstract is standard HTML, but the full article is in PDF format (link to the full article PDF).

Citation:

Worthy, T. H., A. J. Tennyson, M. Archer, A. M. Musser, S. J. Hand, C. Jones, B. J. Douglas, J. A. McNamara and R. M. Beck (2006). Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific. Proc Natl Acad Sci U S A.

(no volume or page numbers as this article has not yet been published in print).

and if you have the chops to read the study, here is a link to the abstract
http://www.pnas.org/cgi/content/abstract/103/45/17 030

looks like the full text is free (unless my institution's IP range has a subscriptionn and it would otherwise be locked down)

In Plastics Day in Surgery, Red Herring reports that an international team of U.S. and German researchers has developed a new kind of plastic that can shift between three different shapes when the temperature increases. Even if these polymeric triple-shape materials have not emerged from the lab, they could eventually be employed as removable stents and self-closing fasteners used by surgeons and more generally by the healthcare industry. But read more

This research work has been done partially at the MIT in Professor Robert Langers research lab. Please note that Ive already covered a previous Langers project in "Light Used to Design Shape-Shifting Plastics" (April 14, 2005).

For this new kind of plastic, Langer worked with Professor Andreas Lendlein, director of the Institute of Polymer Research at the GKSS Research Center in Teltow, Germany, and his team.

This research work has been published online before print by the Proceedings of the National Academy of Sciences (PNAS) under the name "Polymeric triple-shape materials" (November 20, 2006). Here is a link to the abstract.

Shape-memory polymers represent a promising class of materials that can move from one shape to another in response to a stimulus such as heat. Thus far, these systems are dual-shape materials. Here, we report a triple-shape polymer able to change from a first shape (A) to a second shape (B) and from there to a third shape (C). Shapes B and C are recalled by subsequent temperature increases. Whereas shapes A and B are fixed by physical cross-links, shape C is defined by covalent cross-links established during network formation.

The triple-shape effect is a general concept that requires the application of a two-step programming process to suitable polymers and can be realized for various polymer networks whose molecular structure allows formation of at least two separated domains providing pronounced physical cross-links. These domains can act as the switches, which are used in the two-step programming process for temporarily fixing shapes A and B. It is demonstrated that different combinations of shapes A and B for a polymer network in a given shape C can be obtained by adjusting specific parameters of the programming process.

Below is a series of photographs illustrating this triple-shape effect. On the left is a tube which could be used as a stent and on the right is fastener consisting of a plate with anchors. From top to bottom, you can see the shape evolution when the temperature increases to 40C (in B) and 60C (in C). (Credit: MIT/GKSS Research Center). This image has been extracted from the PNAS paper mentioned above.

Picture

In "Morphing Materials Take On New Shapes," Technology Review describes this process in plain English.

Lendlein says the key to the new structures was developing two types of polymers that have distinct melting points. At room temperature, the material holds its first shape. But when heated above a certain temperature, areas throughout the material soften, allowing it to change to an intermediate shape. At a yet higher transition temperature, the rest of the material softens, allowing the structure to take its final shape.

But what would be these

Here are some sources from 2 Journals one by Dr. Saba and others http://www.pnas.org/cgi/content/abstract/103/46/17 384 and this one that seems to support the view on Lyase increasing sensitivity to Cisplatin chemotherapy for Lung Cancer http://mcr.aacrjournals.org/cgi/content/abstract/3 /5/287

Wow. That link took an interesting scientific report and then added a stupendous amount of stupidity. Here's the original source: http://www.pnas.org/cgi/content/abstract/172510699 v1
Here's why scientists believe two ape chromosome pairs fused into one human chromosome pair (which your link claims is ridiculous without any explanation): http://www.gate.net/~rwms/hum_ape_chrom.html

"The common ancestry scenario presents two predictions. Since the chromosomes were apparently joined end to end, and the ends of chromosomes (called the telomere ) have a distinctive structure from the rest of the chromosome, there may be evidence of this structure in the middle of human chromosome 2 where the fusion apparently occurred. Also, since both of the chromosomes that hypothetically were fused had a centromere (the distinctive central part of the chromosome), we should see some evidence of two centromeres."

Read the rest of the document to see how these two predictions made by the theory of common ancestry turned out to be correct.

This topic is nothing new. University of Michigan, Stanford. Human Breast Cancer Prospective identification of tumorigenic breast cancer cells. Proc Natl Acad Sci U S A. 2003 Apr 1;100(7):3983-8. Epub 2003 Mar 10. Erratum in: Proc Natl Acad Sci U S A. 2003 May 27;100(11):6890 http://www.pnas.org/cgi/content/full/100/7/3983 Therapeutic implications of cancer stem cells. Curr Opin Genet Dev. 2004 Feb;14(1):43-7. Review

From the Proceedings of the National Academy of Sciences

http://www.pnas.org/cgi/content/abstract/060586510 3v1

FTFA:Journal reference: Proceedings of the National Academy of Sciences (vol 103, p 17979)

But going to the PNAS home page, the largest page number in the current issue (which is v.103) is 17063. Accessing the PNAS Early Edition page and searching for "pain" or "saliva" doesn't turn up anything which seems relevent. So where do I read the original article?

Maybe Newscientist should start using the DOI system so that we can easily resolve and find the original article.

FTFA:Journal reference: Proceedings of the National Academy of Sciences (vol 103, p 17979)

But going to the PNAS home page, the largest page number in the current issue (which is v.103) is 17063. Accessing the PNAS Early Edition page and searching for "pain" or "saliva" doesn't turn up anything which seems relevent. So where do I read the original article?

Maybe Newscientist should start using the DOI system so that we can easily resolve and find the original article.

FTFA:Journal reference: Proceedings of the National Academy of Sciences (vol 103, p 17979)

But going to the PNAS home page, the largest page number in the current issue (which is v.103) is 17063. Accessing the PNAS Early Edition page and searching for "pain" or "saliva" doesn't turn up anything which seems relevent. So where do I read the original article?

Maybe Newscientist should start using the DOI system so that we can easily resolve and find the original article.

What the article actually said was

1 gram of opiorphin per kilogram of body weight achieved the same painkilling effect as 3 grams of morphine

Also, I have to call shenanigans on your claim that 3 grams of morphine will stop one's breathing. Did you just pull that number out of your ass? Here's some real info from the MSDS for morphine sulfate, which says

Morphine sulfate anhydrous: Oral rat LD50: 461 mg/kg; oral mouse LD50: 600 mg/kg

In other news, I wonder why I haven't been hearing more about tetrodotoxin (from pufferfish) which is a highly effective pain killer in basically homeopathic doses. Maybe the small dose is the reason we haven't heard anything--hard to make a profit on microgram quantities of an easily obtained natural product.

They isolated a peptide which inhibits two enzymes that chew up enkephalins, the body's natural pain killers. Inhibiting these makes the naturally-released enkephalins hang around longer. The problem is that peptide drugs have a checkered history. See the article linked below.

http://www.pnas.org/cgi/content/abstract/060586510 3v1

Do they realize that they are implicitly suggesting that Europeans have bigger brains than Africans?

Where did they say that ? There's nothing like that in their declarations. It's not in the original paper either. All they say is that apparently, a certain allele of this gene 1) was introduced into our gene pool recently, even though it originated long ago and 2) was massively favoured by natural selection, to the point of being present in 70% of the modern population (though more so in Europe than in Africa).

However, for some reason, people spontaneously jump to the conclusion that it somehow favours "bigger brains" - as indicated by the ludicrous, sensationalistic headline of TFA. And of the /. headline. And your own comment.

Draw your own conclusions as to what it implies about the psyche of the average journalist/slashdotter...

I hate it when Slashdot reports some hyped-up university press release as news. If the editors don't want to figure out whether something is truly a breakthrough or an important discovery, they should just stick to reporting stories from the high-profile journals (Science, Nature, etc.).

If the journal article is available for download, the editors should include a link to it, in addition to the obligatory AP/Reuters version for morons. Here is the Neanderthal article from PNAS. See? Easy.

Rather than a crappy overview from CNN, here's the original article's abstract. In fact, it looks like it's in PNASes open access section, so you can all download the PDF for free.

They're basically studying a haplogroup of the microcephalin gene, and show that this gene probably entered the human lineage before 37KYA. The other haplogroups have coalescent times of circa 100KYA (which is around when Homo sapiens arose).

They then use some statistical magic to show that the early coalescence time for the D haplogroup was probably a result of introgression into the population - i.e. it came from another population. Note that they don't stress that it was Neanderthals, it could have been any archaic Homo lineage.

I'm not sure what to make of this yet, as far as I'm aware there's some very strong evidence AGAINST interbreeding between Neanderthals and Humans (e.g. Svante Paabo's work etc)

See this paper for a detailed treatment of how the family tree of the primates can be reconstructed by the retrovirus sequences in our genes.

Pretty much the only available response from the ID crowd is that God created false evidence to test our faith.

Colour analysis is interesting but it's well known that an artist's colour usage changes over time (a famous example being Claude Monet and his eye cataracts). Brush stroke patterns, on the other hand, seem to change less. There was an interesting paper in 2004 in the Proceedings of the National Academy of Sciences on using wavelet analysis of brush stroke marks to separate originals from imitations and to detect areas of paintings that had been reworked.

Of course these are all just tools that add evidence either way, not proof of originality or forgery. I suspect that using both colour and brush stroke analysis would do a better job than just one or the other.

Colour analysis is interesting but it's well known that an artist's colour usage changes over time (a famous example being Claude Monet and his eye cataracts). Brush stroke patterns, on the other hand, seem to change less. There was an interesting paper in 2004 in the Proceedings of the National Academy of Sciences on using wavelet analysis of brush stroke marks to separate originals from imitations and to detect areas of paintings that had been reworked.

Of course these are all just tools that add evidence either way, not proof of originality or forgery. I suspect that using both colour and brush stroke analysis would do a better job than just one or the other.

So on top of worrying about global warming, it seems we should also worry about the physics that govern the orbit of Earth around the sun.

DNA isn't an especially robust molecule. It probably didn't survive that long. It is prone to a variety of reactions that will degrade it over time relatively quickly. Though it was originally thought to survive much longer, DNA older than a million years is now considered pretty dubious, and is likely contamination from other sources, such as soil microbes, or it is degraded fragments with no meaningful signal left in them (e.g., older DNA extracted from fossils tens of millions of years old contains roughly equal left and right amino acids, whereas living tissues contain all left ones, implying the DNA has been severely degraded). Previous discoveries from fossils tens of millions of years old (e.g., from old amber) have proven unreproducible. There's a good review in this PDF format paper by Hofreiter et al., 2001.

By contrast, some organic molecules, such as collagen, are much more durable than DNA, and could plausibly survive much longer in the right conditions, such as if embedded in the minerals that form bone. This general fact has been known for a long time (those papers are from the 1960s and are both PDFs), though how old such remains might ultimately be found is still uncertain. Also, even if the organic molecules were severely degraded, it doesn't mean they vanish completely -- some degraded C-bearing organic residue might remain as long as it wasn't dissolved away, and it could still preserve the shape of the original tissues, even if it wasn't compositionally the same anymore.

Some organic molecules are extraordinarily durable and occur as fossils routinely. The sporopollenin that forms the cell wall of spores and pollen is like the "plastic garbage bag" of organic materials. It can survive multiple passages through the digestive system of animals, and still be intact. Fossil pollen and spores are often recovered from sedimentary rocks essentially unchanged, except for a bit of thermal alteration, and geologists use potent acids like concentrated HCl and HF to dissolve the minerals away, but the pollen and spores are untouched!

Finally, even if the organic molecules themselves get destroyed (e.g., it isn't, say, collagen anymore), minerals could precipitate in contact with the soft tissues and preserve their shape at microscopic scale. The soft tissue isn't actully there, but the structure is. Such preservation is rare, but is known for other types of soft tissues in an older dinosaur (the linked example of the dinosaur Scipionyx does show soft-tissue structures, such as intestines, but they are all mineralized).

The American Thinker has the link to what I believe is the actual report being discussed. It's always nice to be able to get to the actual source material, instead of reading what someone else is telling you it contains.

That's because this time Piquepaille hasn't written anything stupid. Thank goodness, he seems to have learned the lesson and now he has relied on work published in a refereed journal (full article at PNAS), and not some stupid press release with a bunch of buzzwords.

So, guys, where are the Popeye jokes? C'mon, you're too slow!

The bed bug, Cimex lectularius, has a unique mode of copulation termed "traumatic" insemination [Carayon, J. (1966) in Monograph of the Cimicidae, ed. Usinger, R. (Entomol. Soc. Am., Philadelphia), pp. 81-167] during which the male pierces the female's abdominal wall with his external genitalia and inseminates into her body cavity [Carayon, J. (1966) in Monograph of the Cimicidae, ed. Usinger, R. (Entomol. Soc. Am., Philadelphia), pp. 81-167]. Under controlled natural conditions, traumatic insemination was frequent and temporally restricted. We show for the first time, to our knowledge, that traumatic insemination results in (i) last-male sperm precedence, (ii) suboptimal remating frequencies for the maintenance of female fertility, and (iii) reduced longevity and reproductive success in females. Experimental females did not receive indirect benefits from multiple mating. We conclude that traumatic insemination is probably a coercive male copulatory strategy that results in a sexual conflict of interests.

Can you cite some references as regards this? There's certainly an assumption in the community that dolphins are intelligent animals, but I couldn't find anything documenting this other than anecdotal stories ... Please understand, I'm not saying that they're not intelligent, just healthily sceptical.

So if intelligence was directly related to brain size then such claims ought to stand. And I guess that's the whole point of Manger's article - dolphins might be highly socially organised animals, but their level of intellect is not as great as their brain size alone would suggest. (And from the abstract, one of the reasons for that surrounds the different cellular composition of the dolphin brain, which is especially interesting considering the Marino, et al, 2000 paper cited above)

No they wouldn't! It's just a barrier - its purpose is irrelevant.

The issue is how an animal deals with that barrier (*). But your point about not being able to detect the net (either by echo location or sight) seems valid enough (although after swimming into it enough times you'd reckon they'd work it out - again, it's a question of the ability of the animal to reason rather than just interact with their environment ...)

(*) A dolphin - if aware at all - should be well aware of the fact that the sea surface is not the end of its spatial confines. Trap a human in a room with a pool of water, completely enclosed to the water boundary, and it's highly likely that the human will dive under the water in order to see if the walls continue, or if there is a hidden way out.

Every human on Earth can trace our ancestries to someone who lived as recently as the Abraham Lincoln administration. Unless they spent some generations on another planet, or were recently created by an upstart god who got funding for Creation 2.0.

Really, what an insipid take on human descent. The writers might find plenty of inspiration in thinking that every warring religious faction is made of mere cousins. But the real agenda here is to say that our "common ancestors" were Adam and Eve, cryptoreligious "science" that insists the world was created around 6-7000 years ago. Statistical oversimplifications claiming "mathematical certainty" are easy meat for half-bright reporters. But when they don't bother to explain how isolated populations like deep Amazonian tribes factor into the "probability model", it's clear they're looking for data to fit their foregone conclusion. People who first encountered Europeans in the past few dozen years, whose ancestors migrated from Asia probably 30,000 years ago, are the obvious distant relatives to explain, not Palestinians and Jews who have already been experimentally demonstrated.

(from the article I linked: "Contact mechanical models suggest that self-cleaning occurs by an energetic disequilibrium between the adhesive forces attracting a dirt particle to the substrate and those attracting the same particle to one or more spatulae. We propose that the property of self-cleaning is intrinsic to the setal nanostructure and therefore should be replicable in synthetic adhesive materials in the future.")

Cell membranes may well have formed independently of other elements of protolife. For example, fatty acid molecules can can spontaneously self-assemble into vesicles and tranport protons into their interiors, providing a pH gradient that could serve as an energy source for other processes

ven i remember witnesses saying things like car-bombs, truck bombs, and even missles. Which witness do we actually trust? The ones the government backs up?

Thanks! I've dug out the direct link:

http://www.pnas.org/cgi/content/abstract/060238210 3v1

Here's the first paper:

http://www.pubmedcentral.gov/articlerender.fcgi?ar tid=164507

and a nice website from the research group with lots of background:

http://www1.wfubmc.edu/pathresearch/srmouse/part1. htm

Wouldn't the reverse of cell division simply be cell multiplication? That doesn't sound so hard.

Here is a link to the original paper on which the article is based:

http://www.pnas.org/cgi/search?pubdate_year=&volum e=&firstpage=&DOI=&author1=halloy&author2=&title=& andorexacttitle=and&titleabstract=&andorexacttitle abs=and&fulltext=&andorexactfulltext=and&fmonth=Ma r&fyear=2006&tmonth=Apr&tyear=2006&fdatedef=1+Janu ary+1915&tdatedef=4+April+2006&tocsectionid=all&RE SULTFORMAT=1&hits=10&hitsbrief=25&sortspec=relevan ce&sortspecbrief=relevance&sendit=Search

Does anyone with a subscription to the National Academy of Sciences care to
post the complete text?

I do that too - after going through a junction, look back and see which direction to take (two adjacent T-junctions with staircases are probably the hardest).

I've also noticed that when taking a new route for the first time, such as finding a room in a campus build never visited before, the outgoing path always seems twice as long as the return path.

There was an article about how London taxi drivers had larger hippocampi regions>/a> when compared to non-taxi drivers.