30 May 2013

Eleven years of science blogging

Eleventh anniversaries are tricky. I mean, when you hit ten, it’s like watching the odometer on the car roll over and you go, “Look at all the zeroes!” It’s a whole new order of magnitude. But after that, that leading numeral “one” is just stuck there for year after year.

Today is the eleventh blogiversary of NeuroDojo. I’m very happy about that, and with the longevity of this project.

Thanks to:

  • Neil Gaiman for the original inspiration to start this.
  • Blogger for continued hosting and service; literally from the very beginning.
  • Flickr for being my best source of Creative Commons graphics.
  • You, even though you readers and commenters are slightly too numerous to single out.

Despite a post that reflected some weariness earlier this week, I see no end in sight for this blog. It’s still fun.

P.S.—It seems appropriate to include this “Blogging for the long haul” session I did with the mighty Sci at Science Online:

Watch live streaming video from scienceonline at livestream.com

Still not explaining the masks.

Related posts

Ten years of blogging
Science Online 2013: “Blogging for the long haul”
“Blogging for the long haul” session up!

Photo by imago on Flickr; used under a Creative Commons license.

29 May 2013

Which is harder: resurrecting a mammoth, or a scientific career?

Woo-suk Hwang’s career seemed to have flamed out a few years ago among charges of data fabrication.

Today, I read that he is still doing science. And that he is part of a deal to clone a mammoth.

This is surprising to me in several ways. First, that Hwang is still doing any sort of science at all caught me off guard. Second, it is a bit weird that of all the things Hwang’s name re-emerges in connection with, it would be something as fringe sounding as mammoth cloning.

I am also surprised that in the press release, Hwang’s ethical issues are notable only for their absence:

Last year, Grigoryev’s Northeastern Federal University signed a deal with cloning pioneer Hwang Woo-Suk of South Korea’s Sooam Biotech Research Foundation, who in 2005 created the world’s first cloned dog.

In contrast, Wired UK does not overlook this:

Also, while Northeastern University did sign a prominent agreement with South Korea's Sooam Biotech Research Foundation in 2011 to clone a mammoth using recovered mammoth bone marrow, there has been little news from the programme since. Many observers have been sceptical it can achieve its aims, especially as it's led by geneticist Hwang Woo-Suk -- the man who was exposed for faking research in 2006 when he claimed to have cloned human stem cells.

Nor does CNET:

North-Eastern Federal University has partnered with controversial South Korean cloning scientist Hwang Woo-Suk (who was found to have faked data involving a procedure to clone human embryonic stem cells) for a mammoth-cloning effort.

What should the reporting of this story be? Should Hwang’s past be mentioned? I have mixed feelings about this. On the one hand, I do believe that people can change. Hwang’s past may not be relevant to this project. Hwang did achieve many genuine successes, notably the first cloned dog, Snuppy. The scientific community has, in general, not given people found guilty of data fabrication second chances. And Hwang’s record is, well, note-worthy.

External links

Russian scientists make rare find of 'blood' in mammoth
Scientists poke frozen mammoth, liquid blood squirts out
Scientists uncover frozen mammoth, blood flows out
New mammoth comes with grains of salt
Nature’s special report on Woo-suk Hwang

Frankenstein and Galileo, revisited: are they the same story?

I’ve been following the story of Eric Weinstein with some interest, since his work was promoted in the Guardian last week (here and here). I was thinking about why it has attracted so much attention. I thought back to an earlier post of mine, in which I claimed there are two extremely popular science narratives that we tell over and over and over again. One is Frankenstein (science leads to tragedy) and one is Galileo (science triumphs!).

The initial Weinstein articles very much set the tone, raising the possibility that Weinstein might be one of these Galileo type figures: the plucky, lone outsider taking on the establishment. Jha writes (my emphasis):

He may have an impressive CV, but Weinstein is in no way part of the academic physics community. ...

David Kaplan, a particle theorist at Johns Hopkins University in Baltimore, has seen and discussed some of Weinstein's ideas with him. On the plus side, Kaplan says it is "phenomenal" that someone coming from outside academia could put together something so coherent. "There are many people who come from the outside with crazy theories, but they are not serious. Eric is serious."

In response, established jobbing scientists in academia stepped into their proscribed role as stuffed shirt party poopers (my emphasis).

That is not to say he doesn't have anything to contribute, but he will have to go through the proper channels. Physicists are inherently conservative. New claims, especially bold ones, face stiff resistance. That's for a good reason: faster-than-light neutrinos, anyone? ...

Grand claims like Weinstein's would – in the normal course of science – be accompanied by a technical paper explaining their foundations. We could then take a deep breath and puzzle over whether they're consistent with the vast knowledge of nature arising from centuries of experiment and observation.

Jennifer Oulette’s post also fits that mold. Oulette is a smart enough storyteller to recognize the importance of the way the story has been framed as a potential a Galileo-style triumph in giving this story “legs”:

Admittedly, it’s a very seductive narrative. Who doesn’t thrill to the idea of an obscure unknown genius toiling away in the shadows, snubbed by the stuffy, closed-minded academic establishment, who defies the odds and manages to achieve what all those brilliant scholars failed to do, thereby ensuring his or her scientific immortality?

The story is important. In thinking about Weinstein’s lecture being framed as a Galileo-style story, it occurred to me that Frankenstein and Galileo are not two stories; they are one story.

Pride goes before a fall.

Frankenstein and Galileo are both stories of pride going before a fall, and then getting knocked down a peg. The only difference is in who has the pride. In Frankenstein, it’s the scientist. In Galileo, it’s the establishment.

This is perhaps nor surprising, given the nature of science. Science is about determining the nature of reality. And reality always wins. A story that is truly about science will always have anyone who wants to live with their wishes, or deny the facts, or think they can trump the natural world losing in the end.

I am still looking for the shapes of other scientific stories. It seems to me that the most common one in reality makes an uninteresting one in narrative: “Work very hard for a long time, and maybe you can to make a few small dents in our ignorance.”

Additional: I made a few comments about this on Andrea Kuszewski’s post on G+.

Related posts

Frankenstein and Galileo

External links

Roll over Einstein: meet Weinstein
Eric Weinstein may have found the answer to physics' biggest problems
Weinstein's theory of everything is probably nothing
Dear Guardian: you’ve been played
An Outsider’s Theory of Everything
A tale of two Oxford talks
David Nutt and science’s Galileo complex

28 May 2013

Tides and doldrums in science communication

Sometimes, you feel tired. Or small. Or both.

Last week, I went after a claim about “immortal lobsters.”

No, lobsters are not immortal. Lobsters have shorter lives than humans. But there is a tiny little sliver of truth that gets mangled somehow into a bigger claim that “lobsters are immortal.”

I’ve spent quite a bit of time working on the post (which has been updated several times), tracking down references, making pictures, and editing Wikipedia. I was gratified by the response to my post. It was one of my most popular blog posts in a long time. But then, I was dishearted to see that my posts didn’t even have 1% of the reach of a silly lobster picture. And I probably shouldn’t have searched Twitter for “immortal lobsters” to see how many people were accepting this and retweeting this claim.

Last night, I realized I had it easy. At least I don’t have to put up with the stuff the real marine biologists have to deal with, like a cable television network promoting the idea that mermaids are real.

Seriously. What the hell.

Because it apparently needs saying... mermaids are not real.

You want to make a dent in the foolishness. But sometimes, you just wonder if you can. 

And then we scientists get told we are not doing enough.

What about the rest of you guys doing great work that not enough people know about? Who’s helping you communicate what you do?

Sigh. You mean besides blogging non-stop for eleven years as of this week?

Scicurious has a long response to that, which says a lot of things I would probably say. I guess I’ll just add here that I can’t compete with viral memes and entire television networks. Even if I wasn’t trying to teach students and do actual original research, too, how far could I go when the tide seems so relentless and so fast?

This is not to say that I am going to give up. This is a good fight. But sometimes, you wish there was a lull in the fight instead of a never-ending battle.

Additional, 29 May 2013: Apparently, this week’s “mermaids” show gave the network that aired it its biggest audience ever. Hope for humanity fading...

More additional, 29 May 2013: If my post is one of fatigue, Bug Girl's post bookends mine with wonderful enthusiasm. Hope for humanity rising...

External links

Why Science Needs Help Talking About Itself
Calling all Brave Travelers
Insect Carl Sagan and science communication

Related posts

All lobsters are mortal
I want to be Carl Sagan, but can’t

Tuesday Crustie: Be gentle

You may need to click to enlarge to see the fine print on this one...


23 May 2013

All lobsters are mortal

This appeared earlier today on the Facebook feed I Fucking Love Science:


Argh!


I remember seeing a shark documentary as a kid, hosted by Burgess Meredith, if I remember correctly. It made the same basic claim about great white sharks: too big to have predators, nobody had ever seen them die except by accident or by human hands, blah blah blah, therefore “some have suggested” they are immortal.

That I can remember the end of the show all these years later shows you what a terrific close the “immortal” idea makes. But it only sounds plausible because of our disconnect with that natural environment. It plays on our lack of knowledge about the natural world, and that we have a hard time tracking these sorts of things. It’s like asking most city dwellers, “Have you ever seen a baby pigeon?” “No, I haven’t. And you know what, I’ve never seen a dead pigeon, either! Oh my goodness, pigeons must be immortal!”

Sharks and lobsters have a few things in common, too, that makes the “immortality” claim easy to make. They live in the oceans, which means they are hard to track, and few people have first hand experience with them. They are long lived species, and it’s not easy to look at one and know how old it is. Wolff (1978) says of lobsters:

The scanty data presented above demonstrate the great difficulty in estimating the age of the very large lobsters.

When you add in “they only die from external causes,” you have a huge out. Most animals, including humans, die from external causes, broadly construed. Sure, a predator is an external cause. A bacterial or viral infection is an external cause. What would not count as an “external cause”? The definition is so loose that you can make exceptions for almost every possible counter-example.

And, of course, it links out, not to an actual scientific paper, which would be the sort of action you might expect from a group that proclaims to love science, but to a radio interview.

This is not a slap against the participants in the interview. Jelle Atema is a good scientist with real bona fides. But this radio interview is a long way from the sort of careful science you would need to do to show lobsters are “functionally immortal.”

There is some interesting science to this. Many decapod crustaceans have indeterminate growth (mentioned by Vogt 2008, 2010, who cites others). This means that they keep growing throughout their life, and do not have a set upper limit for size. It’s not just lobsters that do this, as far as I know; crayfish do, too. Lobsters are probably in this meme because they get so much larger than crayfish. It’s easier to people to believe a big animal like a lobster could be so much older than a small animal like a crayfish.

There is about one paper that I have been able to find on lobster longevity by Klapper and colleagues (1998). The introduction says:

Lobsters grow continuously throughout their lifespan, only decreasing growth rates with age. Furthermore, and again in contrast to humans, they are able to regenerate whole limbs even at a high age.

This cites a book chapter by Govind, on... muscle innervation?! The chapter talks a little bit about sarcomeres being added throughout life, but that’s about it. It’s not a chapter on aging and senescence.

More provocatively, the abstract of the Klapper and colleagues says (my emphasis):

Lobsters (Homarus americanus) grow throughout their life and the occurrence of senescence is slow.

But there is no citation for the “slow senescence” claim. And there is no original empirical data supporting that in the Klapper paper (e.g., longevity and activity and health and mortality data). The paper shows that adult lobsters still make an enzyme called telomerase, but it does not show that lobsters are long lived because of it.

How old does this “functionally immortal” lobster get? If lobsters really were “functionally immortal,” why would you not expect them to live for centuries?

Wolff (1978) wrote:

I also believe that Herrick gets pretty close to the truth in his poetic conclusion (1911: 199): “Giants weighing from 25 to 35 pounds [11.5-16 kg] have possibly weathered the storms of life half a century or more”.

More recently, Sheehy and colleagues wrote (1999; my emphasis):

The exceptional ages attained by some of the largest lobsters (males: average 31 years, maximum 42 ± 5 years; females: average 54 years, maximum 72 ± 9 years) are explained by ageing theory, indicate natural mortality rates, M, of 0.15 and 0.08 for males and females, respectively, and point to the existence of an offshore refuge.

Bodnar (2009) has a table that puts the oldest lobster on record in the 50-100 range; a bit more liberal than Wolff or Sheehy and company. Bodnar cites Finch (1990), which again does not seem to have much more than a table with an estimated maximum lifespan, connected to another reference I haven’t been able to track down. Nobody seems to define what “slow senescence” is, or how it has been measured in lobsters.

And to make things more complicated, “lobster” covers a lot of not very closely related species, and they have different maximum lifespans. Caribbean spiny lobsters (Panulirus argus) probably live around 20 years, maximum (Maxwell et al. 2007).

Regardless, a “functionally immortal” animal that has a shorter recorded maximum lifespan than a human? Colour me unimpressed.

For such a bold claim, it has been disappointingly hard to track down the real science. It’s also disappointing to see such a credulous claim come from a source that contends it fucking loves science. I think it is fair to call this one:


Sadly, I suspect this myth might have a longer lifespan than many lobsters.

Additional, 24 May 2013: Fighting fire with fire. Fire, and frickin’ awesome big crustaceans.


Additional, 26 May 2013: Welcome Redditors who found this post though this thread.

I also found this meme, made three days ago, apparently in response to the I Fucking Love Science post.


I got criticized a bit on I Fucking Love Science for promoting this post by characterizing the original IFLS picture as saying lobsters “live forever,” when the original picture said, “functionally immortal.” This meme shows that people are not picking up on the nuance. “Functionally immortal” became “biologically immortal,” which, I think, shows people are just going to remember “immortal.”

So, at this point, the original picture on I Fucking Love Science was probably seen by a few million people (over five million have liked it, and over four million are talking about it, says Facebook). The meme above has 689,321 views to far. This post has about 5,000 views so far.

I am going to have to put up with people asking me about immortal lobsters for years, aren’t I?

Additional, 27 May 2013: More evidence that people are seeing lobsters as pretty much straight-up immortal:

Is it true Lobsters can’t die from old age, are they immortal apart from sickness and injury?

I also finally turned to what may have been the source of the claim. Wikipedia. A section on biological immortality contained (until I edited):

Some scientists have claimed that (lobsters) could effectively live indefinitely, barring injury, disease, or capture.

The good bit was that it had a reference. To a journal article. With a relevant looking title:

Guerin JC. 2004. Emerging area of aging research: long-lived animals with “negligible senescence”. Annals of the New York Academy of Sciences 1019(1): 518-520. http://dx.doi.org/10.1196/annals.1297.096

Aha! Maybe this would be the source of the claim that lobsters are slow to undergo senescence! Maybe there is actual data!

I got it, and searched for “lobster.” It was fast; there are only two pages in the paper besides the references. It cites Finch (1990), again, with the reference that I haven’t yet been able to track down. Guerin notes that Finch listed several animals that might have negligible senescence, “including rockfish, sturgeon, turtles, bivalves, and possibly lobsters.” My emphasis: possibly.

That’s all. That’s weak stuff compared to “some scientist claim” lobsters could live indefinitely. Instead, lobsters might have little senescence. Maybe.

It seems that the source of all these “immortal lobsters” factoids are whatever research Finch is citing. I’ll continue to try to track it down, and report back on what I find.

Additional, 3 June 2013: The Surprising Science blog also tackles this story. That post is not just a repeat of information here (though this post does make a cameo). There are excellent comments from several other lobster biologists. For instance:

According to Carl Wilson, lead lobster biologist with the Maine Department of Marine Resources, between 10 and 15 percent of lobsters die naturally each year as they shed their exoskeletons because the exertion proves to be too much. Each molting process requires more and more energy than the one before it as lobsters grow in size.

Finally, older crustaceans stop shedding their exoskeletons altogether—a clue that they’re near the end of their lifespans. They run out of metabolic energy to molt, and their worn-and-torn shells contract bacterial infections that weaken them. Shell disease, in which bacteria seeps into lobster shells and forms scar tissue, adheres the crustaceans’ bodies to their shells. The lobster, attempting to molt, gets stuck and dies. The disease also makes lobsters susceptible to other ailments, and in extreme cases, the entire shell can rot, killing the animal inside.

Additional, 30 June 2013: Discovered this version of the meme circulating on Google Plus:


As someone pointed out in the response thread, it’s ironic that a picture of a cooked lobster is used to support the idea of their longevity.

Additional, 4 August 2013: David Shiffman informs me that this claim has resurfaced again on Discovery Channel’s Shark Week programming. Argh... I’ll take this moment to plug the Science... Sort Of podcast, where I will be discussing the “immortal lobsters” claim soon (episode 178, I think).

Additional, 9 August 2013: The Science... Sort Of podcast is now available!

Additional, 25 August 2013: Buzzfeed perpetuates the lobster myth with a video “6 almost immortal animals” (spotted by David Shiffman). Of lobsters, it claims:

They don’t age. They just continue to grow until they are killed. Yum.

Additional, 13 November 2013: Buzzfeed repeats this myth yet again, linking out to the National Public Radio story, via Quora.

Additional, 25 March 2014: A database on ageing includes a list of organisms with “negligible senescence.” It lists eight species, and none of them are lobster species.

Additional, 7 February 2017: The Science Show has an interview with Daniel Bucher from Southern Cross University in a segment about how old that lobster is on your plate. The lobster in question here are spiny lobsters, not clawed lobsters. Neither host Robin Williams nor Bucher address the “immortal lobsters” meme directly, but it directly addresses the issue of age.

Robyn Williams: How old do they grow too?

Daniel Bucher: Well, our oldest one that we could count, you’re testing my memory here, is about 35 years. But there’s also some larger ones, some individuals, depending on what stage of the moult cycle they are at, are hard or easier to read. And we had some of the biggest ones ever caught and unfortunately they were ones that were hard to read. And so I couldn’t tell you how old our biggest one was, I can tell you that our oldest one was certainly more than 35 years old.

This is in line with the estimates for other species in the main post above: big lobsters live about 30 to 50 years. Unfortunately, the technical work hasn’t been published yet. But this is a promising lead in getting a better handle on the age of crustaceans.

References

Bodnar AG. 2009. Marine invertebrates as models for aging research. Experimental Gerontology 44(8): 477-484. DOI:

Govind CK. 1995. Muscles and their innervation. In: Factor, J.R. (Ed.), Biology of the Lobster Homarus americanus, pp. 291–312, Academic Press, San Diego, CA.

Klapper W, K├╝hne K, Singh KK, Heidorn K, Parwaresch R, Krupp G. 1998. Longevity of lobsters is linked to ubiquitous telomerase expression. FEBS Letters 439(1-2): 143-146. DOI:

Maxwell KE, Matthews TR, Sheehy MRJ, Bertelsen RD, Derby CD. 2007. Neurolipofuscin is a measure of age in Panulirus argus, the Caribbean spiny lobster, in Florida. The Biological Bulletin 213(1): 55-66. http://www.biolbull.org/content/213/1/55.short

Sheehy MRJ, Bannister RCA, Wickins JF, Shelton PMJ. 1999. New perspectives on the growth and longevity of the European lobster (Homarus gammarus). Canadian Journal of Fisheries and Aquatic Sciences 56: 1904-1915. DOI: 10.1139/f99-116

Vogt G. 2008. How to minimize formation and growth of tumours: Potential benefits of decapod crustaceans for cancer research. International Journal of Cancer 123: 2727-2734. DOI: 10.1002/ijc.23947

Vogt G. 2008. The marbled crayfish: a new model organism for research on development, epigenetics and evolutionary biology. Journal of Zoology 276: 1-13. DOI: 10.1111/j.1469-7998.2008.00473.x

Vogt G. 2010. Suitability of the clonal marbled crayfish for biogerontological research: A review and perspective, with remarks on some further crustaceans. Biogerontology 11: 643-669. DOI: 10.1007/s10522-010-9291-6

Wolff T. 1978. Maximum size of lobsters (Homarus) (Decapoda, Nephropidae). Crustaceana 34: 1-14. DOI: 10.1163/156854078X00510 http://www.jstor.org/stable/20103244

Hat tip to Chris Vitek for “Someone is wrong” picture.

University of Texas Brownsville struggles while waiting for merger into new Texas university

In discussing the plans for a new research university in South Texas, I have told a lot of people that my institution is not the one that will benefit the most. I told them about how the other institutions in the lower Rio Grande Valley have been struggling. A new article in the Texas Observer documents more officially what I had only heard informally.

It is uglier than I had heard. Not surprising when you get rid of a fifth of your faculty, including many with tenure.

Early in March 2012, UT-Brownsville formed review committees to determine which faculty would stay with the school, and which would be let go. The committees ranked faculty based on advanced degrees or tenure status. Teachers at the bottom of the list got cut. The goal was to create an objective rubric for the type of faculty each department wanted to keep—but some departments were so small, it was obvious who would lose their jobs. Fuss-Sommer, whose layoff came in that second round, calls it “a perfect opportunity to get rid of people you don’t like.” ...

The layoffs began in late March 2012, with 30 adjunct professors who taught trade courses like air conditioning or car maintenance. At the end of April, Fuss-Sommer and 104 other faculty members—nearly a fifth of the school’s 518 total faculty—were also let go. Of those laid off, 53 were tenured. ...

“There’s no consistency to it,” Ramirez says. “Some people are staying without Ph.D.s and other people aren’t. … It really looks like cronyism to me, where they’re just picking all of the people that they want or they don’t want.”

Ramirez calls it a “really baroque system” developed by UT-Brownsville Provost Alan Artibise to “shield what he’s really doing, which is firing tenured professors.”

I truly hope the merger into a new university stabilizes things.

External links

In Brownsville, Two Colleges Split and a Community Suffers

Picture by final_station on ; used under a Creative Commons license.

22 May 2013

Down in the underground, scuds lose eyes but keep genes

When animals live caves full time, their descendents often lose their eyes. It has happened over and over and over and over again, in all different kinds of animals. But how this happens is not obvious. Stephen Jay Gould wrote that some people would use cave fish as an argument that “Lamarck must have been on to something” with his idea that acquired characteristics can be inherited. Well, no, that’s not that case, but it is a good example of how tricky thinking about losses can be.

The latest paper to try to sort out eye loss uses small amphipod crustaceans (Gammarus minus). An advantage of working with this particular species is that some populations live out in the sunshine with us, but several populations have gone down in the underground. In this case, Carlini and colleagues have three separate populations that went into caves, and they have their closest relatives, which are not cave dwellers. Each pair of populations acts as a natural experiment.

The eyes do change with the habitat, as expected. The amphipods that live “above” in springs have eyes with about 40 facets (ommatidia), while the cave dwellers’ eyes have about 5 ommatidia.

Using genetic tests, the team found that the genes for making visual pigments, the opsins, were still intact. They had not turned into non-working genes (“pseudogenes”). The genes for the opsins were extremely similar, and in no way as different as the eyes of these little guys were.

What they did find was that the expression of these genes was dialed way down compared to their surface dwelling relatives:


Carlini and colleagues note that this could be related to the overall reduction of the eye, but they attempted to control for this by scaling expression to the size of the eyes.

Carlini and colleagues suggest that the opsin genes are under some sort of pressure to stay “intact” in this species (contrary to suggestion here that there is an advantage to blindness in caves). But the team doesn’t have a suggestion for what the opsin genes might be needed for, although they suggest it might be a non-visual function.

This doesn’t solve the matter of how the animals are reducing the amount of opsins they make. Presumably there is some mutation in a regulatory gene, perhaps even a gene one specific to the visual system.

They should keep an eye out for that.


Reference

Carlini DB, Satish S, Fong DW. 2013. Parallel reduction in expression, but no loss of functional constraint, in two opsin paralogs within cave populations of Gammarus minus (Crustacea: Amphipoda). BMC Evolutionary Biology 13(1): 89. DOI:

Related posts

“What big eyes you have!”
Turning light and going blind: A tale of caves and genes
Once more into the cave
Better off blind

Picture from here.

21 May 2013

Tuesday Crustie: Burtonesque

Quick! What does this make you think of?


David Legg looked at these, and immediately thought of this:


And thus the stage was set for the fossil to be named Kooteninchela deppi, named for actor Johnny Depp. Here is a reconstruction:


(Okay, yes, strictly speaking this is an arthropod and not necessarily a crustacean, but the press is reporting it as a lobster, so I’m going to let it ride.)

Reference

Legg D. 2013. Multi-segmented arthropods from the Middle Cambrian of British Columbia (Canada). Journal of Paleontology 87(3): 493-501. http://www.psjournals.org/doi/abs/10.1666/12-112.1

Fossil from here; reconstruction from here.

20 May 2013

Baby geniuses: young guppies show number skills

I have vague memories of the first time I counted to a hundred. It felt like one of those landmarks like tying your shoes for yourself the first time, or riding the bicycle more than a few feet without the training wheels or dad holding you up.

Of course, I don't come anywhere near Adam Spencer:

Once when I was about 7, I counted to 10,000 just to check the numbers didn't run out before then #NerdConfessions

Counting large numbers is not something that comes easily for us humans. A new paper claims this little guy, a baby guppy, may be a superior number cruncher as soon as it pops out of mama’s belly:




A couple of years ago, I reported on a paper that looked at the development of “counting” ability in guppies. In that paper, they claimed that it took about 40 days for guppies to develop the sort of ability to distinguish numbers that they had as adults. Now, the same team is back, testing very young guppies again, but this time using new methods.

The team asked these tiny guppies if they recognized numbers of things by showing animals dots while they have them food. Here are the three stimuli the team used.



Both A and B differ in the number of spots, but A also differs in the average sizes of those spots (which the authors call a “continuous variable). C differs in size, but not in the number. This is try to control for the fact that when you change number of things, you also change many other factors, like amount of area reflecting light, etc.

The authors then measured the amount of time the guppies spent near each set of dots as an indication of “preference”, on the assumption that the guppies are more likely to spend time near the dots where they got food if they learned certain dots meant food. If animals don’t learn where the food is, they may well not be able to tell the stimuli apart.

The authors place these pairs of dots at the end of the tank while fish are feeding when they were four and five days old. As a control, they either feed the fish food or just in a little water without food. On day six, they placed the babies in the tank to see which set of dots they gravitate to. On day seven, they repeat this, but flip the positions of the dots.

The fish were significantly more likely to be around the set of dots that promised food when they differed by number (A and B, above), but not when the dots varied in size. That said, the guppies were not great at this. The guppies got it right only 60% of the time, which is only a slight improvement on a coin toss.

However, the authors themselves admit that this paper is hard to compare with their previous one because the stimuli are so different. The previous paper used other live fish as the stimulus, not just static dots. They also note that this test is slightly different from other training tests, which generally ask the animal to do something even more specific than “hang out at one end of an aquarium.”

It is an interesting suggestion, though, that animals so small and so young can cope with differences in number. But I still think I’ll beat them at counting to a hundred.

Reference

Piffer L, Miletto Petrazzini ME, Agrillo C. 2013. Large number discrimination in newborn fish. PLOS ONE 8(4): e62466 DOI:

Related posts

One fish, two fish... can fish count?

Picture by Shaojung on Flickr; used under a Creative Commons license.

17 May 2013

New university one step closer

The bill proposal the creation of a new university in South Texas (including a medical school) passed unanimously in the House of Representatives a few moments ago. The only legislative step needed now is for Governor Rick Perry to sign the bill into law, which he said he would do.

This means my university will be changing and merging with other institutions and more stuff will expected from us.

Now what? In the words of Amy Pond... “Okay kid.... this is where it gets complicated.” 

There will soon be a zillion nitty gritty details to work out, which have so far been in short supply. 

Colour costs crickets

You probably don’t feel tired when you get a tan.

You probably think your friends feel more or less fatigued depending on whether they are dark skinned or fair skinned (like myself).

We know that differences in colour are important lots of other species besides humans. They can play a big part in an animal’s ability to blend into the surrounding environment, for instance. What might be less appreciated is that being a certain colour might take energy. After all, many colours in animals are caused by pigments: specific molecules that animals have to make in their bodies. Some of those molecules could well depend on molecules that the animal has to get somehow, or make through a physiological process.

Melanin is just such a chemical. Melanin is a dark chemical in lost of insects, but one of the main compounds insects need to make it only comes in food. If you don’t get enough food, you can’t make enough melanin. A new paper by Roff and Fairbairn take this a step further, and asks if melanin might actually be costly for animals to make, with an eye towards evolutionary situations. For instance, how big a benefit in dark colour would there have to be for you to spend the energy to make more dark stuff?

They test this in a clever way. Rather than looking at different colour types of one species, they look at changes in colour of a single species, a sand cricket (Gryllus firmus; above right). When these crickets shed their skeleton, they are very lightly coloured (right): there is no melanin in their new skeleton for a while until it hardens up.

They reasoned that if making all this melanin was costly to the cricket, then crickets with less melanin should have more of some other feature, like the gonads. And that’s what they found. The bigger the gonads in cricket, the less melanin they had. This degree of melanization was highly heritable, too (a score of 0.61, where 0 is not influenced by genes, and 1 is completely determined by genes).

This in no way suggests that this means you shouldn’t tan. Yet.

Reference

Roff DA. & Fairbairn DJ. 2013. The costs of being dark: the genetic basis of melanism and its association with fitness-related traits in the sand cricket. Journal of Evolutionary Biology: in press. DOI:

Moth picture from here; cricket picture from here; cricket molt from here.

16 May 2013

Sudden realization

I genuinely had this thought walking home last night...

Comments for first half of May 2013

The Singular Scientist examines oft-given public speaking advice to calm nerves before a presentation.

Small Pond Science is looking for summer reading. If you’re an educator, I like Design for How People Learn.

I really liked Doctor Becca’s reflections on being mid-way through the tenure process, especially the bit about fame. Also excellent is Small Pond Science’s reaction to that.

Love Girls Are Geeks advice on how to talk with a scientist.

15 May 2013

“Offshore” journals

Jeffrey Beall is doing much to draw attention to issues surrounding the validity of new journals. He is in the news today because a publisher is threatening to sue him for one billion (yes, billion with a b) dollars.

But I wanted to comment about a post from April about Hindawi Publishing. Beall ends:

Is this the future of scholarly publishing, dumbed down and offshore?

The “offshore” comment has a slightly snobbish overtone. It implies that, “Of course, some places simply can’t produce good scholarship.” I am sensitive to this, since I realized my own posts made similar jabs at the national origin of many journals. I realized that was a little unfair.

I agree that researchers some countries do face bigger challenges in producing top-quality scholarship. It could be due to lack of infrastructure, distorted publishing incentives, or an overly cliquish academic culture. But such challenges need to be examined and spelled out, not made in an offhand way.

External links

Hindawi’s Profit Margin is Higher than Elsevier’s
Publisher Threatens to Sue Blogger for $1-Billion

Related posts

As Nigeria is to banking, India is to science publishing
Science Online 2013 appetizer: Open access or vanity press?
The center of knowledge

14 May 2013

Tuesday Crustie: Butter me up


The eagle-eyed among you may be able to determine an establishment where you could get a pair of these for yourself, or for a special crustacean loving man in your life.

Tuesday Crustie: Macro



The photographer identifies this as Orconectes, though not which species.

Photo by Bee Nouveau on Flickr; used under a Creative Commons license.

13 May 2013

Continuing education

“I just want to continue my education.”

I’ve heard this from a few prospective grad students. I understand why they would say they want to continue their education when they’re asked why they want to go to grad school. I imagine for their entire lives, they have probably been encouraged to stay in school. For their entire lives, they have probably been told degrees are a pathway to greater professional success. For their entire lives, education has been an unalloyed good.

But “continuing education” is not a good reason to go to grad school. At the end of a bachelor’s degree, honestly, you should have a pretty darn good idea about how to continue educating yourself. That’s the point of a liberal arts degree. Grad school is a specific education with a specific purpose. Do it if you need the degree for a specific career, or if you love the subject.

I have yet to hear someone who says, “I just want to continue my education” give a good answer if they get asked, “Why?” They often have no plan, and little understanding of what grad school entails.

09 May 2013

Scientific writing seminar

This is a talk I gave to undergraduate research students at the STEM Center earlier today. Come for the tips, stay for the bad jokes!


Additional, 11 May 2013: Now you can follow along with the slides on Slideshare!

08 May 2013

Getaway

A CBS station in Dallas reports of a new invasive species in my state. Now, I work with potentially invasive species, so I don’t want to make light of the biological damage that could be done here, but... this is the invasive species:



The report calls it a giant African land snail, which could be any of several species.

The story concludes:

Unfortunately the snail discovered in the Houston homeowner’s backyard woman’s backyard got away before it could be caught.

Got away? A snail got away. A snail... got away? A snail?!

How does a snail get away? You had one job!

Are you sure this isn’t a publicity stunt for this summer movie?

“Can you hear me now?” The new record holder for hearing

This is our new winner, ladies and gentlemen.


This unassuming moth is a greater wax moth (Galleria mellonella). Don’t let its drab appearance fool you, friends. This is a record-setting animal, with one of the most extreme sensory systems yet found. Its speciality? Hearing.

When you listen to anything, there are two main properties inherent in the sound: loudness and tone. The volume is determined by the size of sound waves; the tone is set by the frequency of sound waves. Humans hear tones where the sound waves vibrate back and forth at several thousand times a second. Something that moves back and forth once a second has a frequency of one Hertz (Hz); a thousand times a second is one kiloHertz (kHz).

People differ in how well they hear sounds at the high end. In particular, you lose the high frequency sounds as you get older. You can test how high you can hear at this website. Note that it stops at 22 kHz, because very few people can hear that high.

Animals, of course, have different limitations than humans. Cartoons often reference a dog whistle, with a pitch that humans can’t hear, but dogs can.


(Note: “Dog whistle” is not to be confused with “wolf whistle.” Know the difference!)


Moir and colleagues did two experiments to show the wax moth’s superior high-end hearing. First, they used a technique to show whether the ear drum (tympanum) was vibrating. If you can’t vibrate something at at the same frequency as the sound, you can’t detect the tone of the sound. They found the ear drum was able to keep up with every frequency they tested.

The critical experiment, though, is the neurophysiology. It doesn’t matter what the ear drum does if the neurons don’t convert anything into a signal. The wax moth has an ear with a grand total of four neurons devoted to picking up sound. Thus, analyzing the signals is fairly straighforward.

They found the moth’s ear could pick up sounds all the way up to 300 kHz. That’s twice as high as the previous record holder:


Sorry, Lymantria dispar. You had a good run.

The wax moth doesn’t hear equally well across the range. It is particularly good at picking up sounds in the 60 kHz range. For the wax moths to hear the end frequency sounds, they have to be much louder. At 60 kHz, the wax moths can pick up sounds of a volume about 50 decibels of sound pressure level (dB SPL); at 300 kHz, the sound has to be more like 90 dB SPL. That’s a loud sound. And at the very high end (280-300 kHz), some of the moths don’t respond at all to even loud sounds, suggesting this is near the upper limit of their hearing.

Why does the wax moth need such amazing hearing? The general explanation for why insects can hear at these high frequencies is because of these:


Bats hunt insects using high frequency sounds, and many insects have evolved ears that can hear the sounds bats make. This does not seem to be coincidence. The bats are thought to be exerting extreme selection pressure on insects, so hearing predators approaching is an adaptive advantage.

In this case, there is just one little puzzle. No bat makes a sound that hits 300 kHz. Why does the greater wax moth ear reach way up that high in the frequency spectrum? The authors suggest that this highly responsive ear allows the moth to react faster to sounds. After all, if your ear can vibrate at 300,000 times a second, and it takes 300 vibrations for the ear to pick up the sound, you could pick up the sound in a thousandth of a second, compared to about a hundredth of a second for an ear vibrating at 20 kHz, like our crappy human ears.

Reference

Moir HM, Jackson JC, Windmill JFC. 2013. Extremely high frequency sensitivity in a 'simple' ear. Biology Letters 9(4): 20130241-20130241. DOI:

Related posts

Good night, Dr. Griffin, where ever you are...
Crickets fly away from bats, but do they run away, too?
Do bright bugs banish bothersome bats?
Let your neurons relax, the predators are gone!

Photo by dhobern on Flickr; used under a Creative Commons license.

07 May 2013

Dynamation no more

I am seeing reports that Ray Harryhausen has died.

If you don't know him, he made screen magic. He did it moving miniatures frame by frame, having only his memory to remember what he’d moved. His work was amazing. And you can trace a straight line from him to so many of today’s science fiction and fantasy films.

If you have never seen one of his movies, watch one this week. Open your eyes and rediscover the wonder of things that can’t possibly be real moving on the screen for you to see.


External links

Ray Harryhausen website

Tuesday Crustie: Micrarium


These copepods are preserved specimens on display in a museum. Now, you might think, “Those are small, so how would you display them?” Like this:


It’s an amazing display at the University College London. They dubbed it the “micrarium,” which is an excellent word. Lovely idea and lovely display.


See more of the display here.

Photos by UCL News on Flickr; used under a Creative Commons license.

01 May 2013

Comments for second half of April 2013

Dynamic Ecology asks how you decide what to publish next.

Reaction Norm asks if grad students should pay for their own degrees.

I have occasionally been known to wear kilts. Scicurious examines a paper proposing an hypothesis on the reproductive effects of wearing kilts.

My IMDb test for scientific jargon makes a cameo in Alex Brown’s post about jargon. Features an ace anecdote that can be used for talking about writing science: “Why do kidneys need cells?”