Not Exactly Pocket Science - panic aboard the Titanic, the rise of polar bears and emasculated frogs

I'm trying something new. Right from the start, I've always tried to write fairly long and detailed write-ups of new papers but this means that on any given week, there are always more stories than time and my desktop gets littered with PDFs awaiting interpretation.

So, I'm going to start doing shorter write-ups of papers that don't make the cut, linking to more detailed treatments on other quality news sources. This is something that I hope science journalists will do more of. It stems from a Twitter conversation where I asked if I should (a) write up short versions of these stories, (b) ignore them, or (c) link to other pieces. People chose a combo of A and C. And if we're being honest, I was really pleased with "Not Exactly Pocket Science" and the name needed a feature to go with it!

These shorter pieces will still be written from primary papers rather than press releases or existing news stories. Give me feedback. Do these add to the NERS experience, or do short articles go against what you expect of this blog? And also let me know if you find better pieces on the same stories, or you don't like the ones I've linked to. Let's turn NEPS into a way of highlighting good journalism elsewhere on the web too.

Panic on a sinking ship - Titanic vs Lusitania

i-dfd2a7cc9e39f5ffd26a711d462ea91f-Titanic.jpgIn 1912, the Titanic famously sank after colliding with an iceberg. Three years later, the Lusitania also met the ocean floor thanks to torpedoes from a German U-boat. Both ships had similar proportions of crew and demographics of passengers. Neither had enough lifeboats and as a result, only about a third of the passengers on either vessel survived. Over a thousand people died in each tragedy. But Bruno Frey thinks that differences in the type of people who died tell us something about human behaviour under crisis situations. The key factor, he thinks, is time.

The Titanic sank in a leisurely 2 hours and 40 minutes, with plenty of time for social norms to influence who made it onto the lifeboats. The Lusitania went under in just 18 minutes, creating a situation where it was literally every man for himself. In both cases, the captains told crew to save "women and children first". But their orders were only deferred to on the Titanic, where women and children were indeed more likely to survive than other passengers. On the Lusitania, people aged 16-35 (their supposed physical prime) were around 10% more likely to survive than other age groups. Likewise, first-class passengers had higher odds of survival aboard the Titanic, when class issues had enough time to manifest themselves but they actually fared worse than the third-class passengers on the Lusitania.  

I usually enjoy attempts to view history through a scientific lens, but in this case, it's difficult to see how much you could really tell from two data points though. Grey's data are certainly consistent with the hypothesis that selfish behaviour is more likely to emerge in crises that unfold more quickly. But so many other factors could have influenced the outcomes - the structure of the ship, the fact that the Lusitania sank during war-time, the fact that they probably knew about the events aboard the Titanic, different perceptions of the odds of rescue, and so on. Indeed, Grey mentions all of these and says that, "There can be no absolute proof of the hypothesis that only time led to such behavioural differences. Ideally, more observations (comparable shipwrecks) are needed to better isolate the potential relevance of time."

More from Mark Henderson at the Times and Jeff Wise at the Extreme Fear blog

Reference: Frey, B., Savage, D., & Torgler, B. (2010). Interaction of natural survival instincts and internalized social norms exploring the Titanic and Lusitania disasters Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0911303107

Jawbone reveals the rise of the polar bear

i-06aec2d6078ea51bd9ec99cb4773c4d2-Polar-bear.jpgA lots of news coverage is devoted to discussing the fate of polar bears, but it's their origins that are now getting some attention. A new fossil jaw from Svalbard gave Charlotte Lindqvist the opportunity to trace the history of climate change's flagship species. Polar bears live and die on sea ice, their remains either sink without a trace or are scavenged, so every new fossil is an exciting find. The new jawbone is approximately 130,000 to 110,000 years old but Lindqvist managed to extract enough DNA from it to sequence the genome of its mitochondria - small power plants within every animal cell, each containing their own genome.

She also sequenced extra mitochondrial genomes from two living polar bears and four brown bears from different areas. A family tree built from these sequences revealed that the jawbone's owner was remarkably similar to the last common ancestor of brown and polar bears, sitting just at the point where the two lineages diverged. By analysing the carbon isotopes of the fossil's canines, Lindqvist deduced that this ancient bear ate sea-going mammals just like its modern cousins do.

Together, this single bone paints the portrait of an evolutionary success story. Within 10,000-30,000 years of their split from brown bears, the polar bears had adapted magnificently to their frosty kingdom and risen to the rank of top predator. Within the next 100,000 years, they had spread across the entire polar realm. As Lindqvist says, they're "an excellent example of "evolutionary opportunism". Whether they'll be swift enough to cope with the current changes to their habitat is another matter.

More from Brandon Keim at Wired

Reference: Lindqvist, C., Schuster, S., Sun, Y., Talbot, S., Qi, J., Ratan, A., Tomsho, L., Kasson, L., Zeyl, E., Aars, J., Miller, W., Ingolfsson, O., Bachmann, L., & Wiig, O. (2010). Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0914266107

Common pesticide turns Kermits into Kermitas

i-3ed8e9c124b7cedcc85398f402af9717-Kermit.jpgTheir testicle shrinks, their testosterone depletes, their sperm count falls, and they stop trying to have sex. Becoming emasculated and impotent isn't a pretty fate for a male frog, but thanks to a pesticide called atrazine, it could be a common one. Atrazine is an "endocrine disruptor", a substance that mimics the effects of sex hormones in the body. Tyrone Hayes has found that it can chemically castrate male African clawed frogs.

Around 10% of the animals actually became fully functional females despite being genetically male. They could even mate with other males to produce viable eggs (albeit ones that only hatched into genetic males). In others, the changes were less drastic but they were still feminised enough to seriously affect their odds of mating successfully. This isn't the first time that atrazine has been linked to feminised frogs and according to previous studies, it affects other groups of animals, from salmon to crocodiles, in the same way. In these species, atrazine switches on the manufacture of aromatase, an enzyme that, in turn, stimulates the production of oestrogen. This flood of hormone may also be behind the feminised Kermits.

Frogs and other amphibians are particularly vulnerable to chemicals like atrazine because of their absorbent skins. Indeed, Hayes emasculated his frogs with just 2 parts per billion of atrazine, a dose that animals would frequently encounter in contaminated areas, and well within levels occasionally found in rainfall. Because of the environmental risks, atrazine was banned in the EU in 2004, but the US still sprays 80 million pounds of this persistent chemical every year. Obviously, this study didn't assess the impact that the chemical could have on frog populations but there's every reason to suspect it as a "contributor to global amphibian declines".

More from Janet Raloff at Science News

More on amphibian conservation:

Reference: Lindqvist, C., Schuster, S., Sun, Y., Talbot, S., Qi, J., Ratan, A., Tomsho, L., Kasson, L., Zeyl, E., Aars, J., Miller, W., Ingolfsson, O., Bachmann, L., & Wiig, O. (2010). Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0914266107

i-77217d2c5311c2be408065c3c076b83e-Twitter.jpg i-988017b08cce458f49765389f9af0675-Facebook.jpg i-6f3b46114afd5e1e9660f1f502bf6836-Feed.jpg i-deec675bab6f2b978e687ca6294b41a5-Book.jpg


More like this

The genome of the extinct woolley mammoth (Mammuthus primigenius) has been sequenced, and reported in Nature. This confirms that elephant genomes are large, like the elephants themselves. It confirms previously proposed relationships amongst the elephants (see phylogeny below) and refines the…
Today (4/25) is national DNA day.  Digital World Biology™ is celebrating by sharing some of our favorite structures of DNA. We created these photos with Molecule World™ a new iPad app for viewing molecular structures. As we are taught in school, the double stranded DNA molecule is a right-handed…
Some people who come to Tet Zoo seem to absolutely despise all those annoying teasers, preemptives and references to things that are yet to come. Others regard these as one of Tet Zoo's key points of awesomeness. Whatever, I am pleased to say that I congratulate you all on your patience and…
It's been interesting to watch as microbiology's own cold fusion debate has been raging. It began with an extraordinary claim about bacteria using arsenate as a replacement when phosphate concentrations are low (1).  It progressed when at least two scientist / bloggers ( here, and here) (not…

definitely adds to the NERS experience. you rock, ed!

Three posts for the price of one. (That's a pretty low price).
Works for me.
My very first comment, I've just immersed myself in the blog-o-sphere a couple of months or so ago and have been a bit shy about contributing. Looks like my first comment will just amount to vague agreement.
In any case, love your work, and I think pocket science is great idea.

By not_hippy (not verified) on 02 Mar 2010 #permalink

It works for me. Off to a good start.

Now, how do we get the science blogosphere to ratchet up the pressure on the US to ban atrazine?

It's difficult to write concisely on scientific and technical topics, and doubly so to make it accessible to the lay person as you do here. More variety on the plate makes for a well balanced meal.

Could atrazine feminised frogs give rise to a geneticly male sexually reproductive population?

I love the new format idea and am also very intrigued by the Titanic story. I have two major problems with Frey's theory: a)there are better ways to explore the human fear response than sifting through historical data b) saving yourself from mortal danger isn't necessarily selfish, or the product of panic. We have to bear in mind what information and what courses of action are available to the people in danger. I explain more on my blog.

Thanks for the comments everyone.

Chezjake - Clicking on the link in Tyrone's name is a good start. And 10% of the frogs are indeed capable of raising a viable new generation. BUT frog males have two Z chromosomes, and if a male mates with a feminised male, all of their offspring will be ZZ males too. So if this carries on, you'd expect the sex ratio to slowly bias towards males, and the paper says that modelling studies have predicted that this could indeed lead to species extinction.

Jeff - I'm not entirely convinced by the study either. In part, I want to use NEPS to highlight studies that are intriguing but that I have issues with and want to discuss. I've linked to your post above.

Keep that feedback coming people. It's tres useful.

I like the new NEPS. A mix of the more in depth articles with short posts is I think a good idea.

While I can certainly see people having problems with Frey's article, I see value in these types of articles. I view them as less "I can demonstrate x" and more, "Hey guys, there might be something here that bears further study."

I like this approach.

Good stuff. Works for me.

By Physicalist (not verified) on 02 Mar 2010 #permalink

I'm a big fan of the new format!

Love this format. I only have to chase the kids off once while I read rather than 3 times so I can think through all the info.

Now, I hope the scientists don't jump on me for being ignorant, but are polar bears now so genetically distant from brown bears that they could not adapt back the other way (i.e. go darker?)

I hate revealing my ignorance, but humility is the first step to knowledge.

I'm rather new here, so I don't feel like I can comment on this new format. Let me just say that I enjoy your blog, and I'm sure I'll continue to enjoy it, whatever you decide about this.

You really do a great job here!


i'm no scientist, but i think a quick answer to your question would be that, given the rapidity of climate change (the industrial revolution only began around 200 years ago), and the fact that the brown bear currently occupies much of the ice-free land of the north, it is unlikely that polar bears could re-adapt to the terrestrial niche (outside of, say, contributing to a hybrid population in the zone both species now inhabit).

By the way, someone on Twitter suggested that I publish NEPS items as individual posts rather than multiple stories per post.


My hand is up for the same format as above, i.e. multiple pocket science stories per post. Does the addition of 'pocket science' posts mean a reduction of 'rocket science' posts?

By not_hippy (not verified) on 02 Mar 2010 #permalink

I like both the long and short ones. The first by giving more information about 1 item in a real story, the second by bigger itemdiversity. Though to my surprise, in these short ones I don't have the feeling missing something. Depending on the paper / subject, perhaps you could make some kind of mix of long and short posts?
For the reading, it doesn't make much difference to me if you put more stories in one post. But separate posts would be clearer to me in headlines and comments.

NEPS is very cool! I enjoy the long posts as well, but for a lot of stuff I would just like to get the jist of it, and this is the perfect format. It would be great if you'd keep it! I also like having multiple short reports in one post. Otherwise it would seem like diluting value: like putting less in a pack for the same price (crude analogy I know...)

Not_hippy - no no no no no no! ;-) NEPS is a supplement to NERS. if I ever get the sense that the quality and the quantity of the longer posts is suffering, NEPS goes.

Toos - actually if I do my job right, you should be able to read the first few paragrahs of any NERS post and get the gist, although I try and have more of a narrative than a traditional news piece and I leave good stuff for the end to reward people who actually RTFA ;-)

Uschi - that was my thought too

Oh and southlakesmom, basically, what Brooks said. V.different for the bears to adapt to, and spread through, a NEW "fresh" habitat than to move back to an "old" one where there's already a successful competitor.

Pls never be afraid to ask questions here. Plenty of people reveal their ignorance
in blog comments without realising it so asking a constructive question is always welcomed

SouthlakesMom, I was always taught that there is no such thing as a stupid question only stupid answers.

The previous commenters are correct, it would be much more difficult (& take too long) for polar bears to use evolution to counteract the loss of their habitat. There is however evidence that as their habitat shrinks & they are moving into areas now occupied by grizzlies which can result in interbreeding. There are reports of hybrids called grolar bears or pizzlies (depending on which breed is the father).

I'd prefer each NEPS article as a separate post, so that each one will have its own headline in Google Reader and they're separately sharable.

By Brian Slesinsky (not verified) on 03 Mar 2010 #permalink

Well worth the NEPS, maybe a 2:1 long post/short post ratio, if they're all three like this. As far as the splitting, I personally prefer them all together, but it wouldn't be much of an inconvenience to split them; sounds like it might be considerably more helpful for the RSS feed folks than it is harmful to me. Still, I agree with the dilution possibility, it's just instinctively nice to have the majority of the articles be the in-depth work that I keep coming back for. If you've got a high ratio of rss feed readers to page viewers, though, might be worth it!

Thanks all; I think I really was wondering whether two separate questions, i.e. adapting as a species as well as interbreeding with other kinds of bears. Hexkid, that is absolutely fascinating -- I wonder what the downstream result of that will be. I'll be watching for stories on grolars and pizzlies!

You realize that the Titanic was an ice-elated event, right - so it's definitely going to snow the numbers....

I like the format of 3 short stories in one. It means you settle down and read the whole post, but get 3 stories.

With the boat sinking stories, it seems that either more data will be fairly readily available (i.e. there is death demographics for other ships that have sunk), or there isn't and there won't be any time soon. If there is the data, I don't know why he hasn't found it, if there isn't the data there is no point saying "we need more data".

I like it! I think keeping NEPS in this format (several quick posts in one entry) is better than spreading them out to several entries.