Moth Eyes

Navigating a demon-haunted world

Partial Lunar Eclipse – June 4, 2012

Partial lunar eclipse, June 4 2012
Partial Lunar Eclipse on June 4, 2012 at 9:55pm. Photo taken from Townsville.

June 4, 2012 at 10:28 pm Comments (0)

Unremyfy

Over at The Daily WTF, one of the authors, Remy Porter likes to add a certain amount of bonus content to the posts. Specifically – Remy’s articles always have a bunch of HTML comments with extra details or jokes, and clicking somewhere in the article produces unicorns.

Well, there’s no sense in letting unicorns go unclicked! That’s why I wrote unremyfy, a script to display the HTML comments inline and highlight where you need to go to get unicorns. What a useful script!

Install unremyfy

February 29, 2012 at 8:31 pm Comments (0)

Moving the skeptics.se caveat banner

One change requested on the Skeptics Stack Exchange is to make the “rapidly changing” caveat on questions like this one more prominent. I liked the idea, so I wrote a user script in the mean time to do it. It adds a border around the right and bottom of the post, leading to the notification.

This will work either in Firefox (with Greasemonkey installed), Chrome (with restart) or Opera. There are extensions for other browsers (GreaseKit for Safari, Trixie for IE), but I haven’t tested with them.

What it does:

  • Adds a border leading to notices (like bounties, current events and lack of references)
  • Makes all notices bold

Download now!

Updates:

  • 1.1: Removed moving to top, using border now
  • 1.0: Original version
February 27, 2012 at 7:57 pm Comments (0)

Photo #20 – Whitetip reef shark

White-tip reef shark
Whitetip reef shark (Triaenodon obesus), photographed in the north of the Great Barrier Reef, on Kalinda’s Far North Expedition.


February 14, 2012 at 12:53 am Comments (0)

What is a newspaper?

If I want to know what a politician is saying, I don’t really need a journalist. The politicians have websites, blogs, twitter feeds and email newsletters. They give speeches, many of which are shown on TV. If all we need to know is what politicians say, we can replace the entirety of journalism with some camera operators, a TiVo, and an RSS reader. If that’s the extent of journalism, it’s probably not a career with much of a future.

If journalism is to be useful, it really ought to do something that a TiVo can’t. A TiVo can’t add context, or check whether the source is lying. It seems to me that those sort of things would be good value propositions for a journalist.

Some good posts recent posts on this topic:

Dr. Free-Ride
If the paper of record views getting the facts right as a style choice, where the hell is the public supposed to get the facts?

Slacktivist
If your mother tells you she loves you and you turn around and repeat, “My mother loves me,” or even the slightly more careful, “My mother says she loves me,” then you’re not a reporter or a journalist. You’re not reporting, just repeating. That’s stenography or gossip, not journalism.

Checking it out is what makes a reporter and what makes a report.


January 14, 2012 at 1:02 am Comments (0)

Cold snaps curtail invasions

ResearchBlogging.orgClimate change not only causes shifts in the distributions of native species, but also allow invasive species to establish new populations. For example, many Caribbean species are taking advantages of warming temperatures, expanding polewards and invading into the south-eastern United States.

Green porcelian crabHaving established themselves, however, it’s not unknown for the invaders to come to pain. For example, in early 2010, the south-eastern United States experienced a particularly cold winter, which came to be known as “Snowmageddon”. After Snowmageddon, scientists found that the populations of several established invaders had crashed, in some cases been entirely wiped out.

Kaplan-Meyer survival curves for the experimental crabsCurious, Dr. João Canning-Clode and his colleagues collected a number of invasive green porcelain crabs (Petrolisthes armatus) to study. They had three groups: one control group would be held at what would be a fairly mild winter temperature at the collection site, one group would go through a cold snap similar to that experienced in January 2010, and one would experience a cold snap which was a couple of degrees even more extreme.

The results were striking. In the control group, 83% of the crabs survived the winter. In the Snowmageddon group, however, only 39% of the crabs survived – and the population that experienced an even colder snap was entirely wiped out. They also noted that cold temperatures caused the crabs to move around less – which, in the wild, would have probably caused them to be more vulnerable to predators and also make it harder for them to find their own food.

The researchers figure that the occasional cold snap may have the effect of stopping invasive species in their tracks – devastating, if not wiping out the populations. However, as the globe warms, extreme cold snaps have been getting less frequent, a trend which is expected to continue.

References

Canning-Clode, J., Fowler, A., Byers, J., Carlton, J., & Ruiz, G. (2011). ‘Caribbean Creep’ Chills Out: Climate Change and Marine Invasive Species PLoS ONE, 6 (12) DOI: 10.1371/journal.pone.0029657

DeGaetano, A., & Allen, R. (2002) Trends in Twentieth-Century Temperature Extremes across the United States. Journal of Climate, 15(22), 3188-3205.

Kodra, E., Steinhaeuser, K., & Ganguly, A. (2011) Persisting cold extremes under 21st-century warming scenarios. Geophysical Research Letters, 38(8).


January 13, 2012 at 1:00 am Comments (0)

Tapeworms like it hot

ResearchBlogging.orgBird tapeworms (Schistocephalus solidus) have three distinct life stages. First, they infect copepods (tiny crustaceans), such as Cyclops strenuus abyssorum. The copepods are eaten by sticklebacks – in this case, the three-spined stickleback, Gasterosteus aculeatus. The sticklebacks are then eaten a bird, in which they breed and produce eggs with which to infect the next generation of copepods.

In order to be infectious to a bird, the tapeworm larvae must grow to a size of at least 50mg. That being said, the bigger the better – larger parasites are far more fertile, producing many times more eggs – which are also larger. Larger parasites also make their hosts less able to breed and more likely to be eaten by a bird.

Parasites infecting organisms which do not control their own body temperatures (such as most fish) are more likely to be directly affected by climate change – a parasite infecting a warm-blooded mammal, for example, can rely on a temperature-controlled living space. To test what impact temperature would have on how infective the tapeworms were, Macnab and Barber (2011) kept two populations at different, static temperatures, within their normal temperature range – 15°C and 20°C respectively – and fed half of each population infected copepods (the others got non-infected copepods).

Temperature, they found, did not affect the likelihood that a fish eating an infected copepod would be infected – in both cases, about half of the exposed fish were infected. However, they found that the tapeworm larvae grew much faster in the warm-water group. 8 weeks in, every tapeworm larvae in the warm-water group had reached the 50mg size necessary to infect a bird – whereas none of the larvae infecting the cooler group had. In fact, in the warmer population, the average size of the tapeworms was twice the size they needed to infect a bird. They estimate that this difference would allow each parasite to produce at least an order of magnitude more eggs than in the 15°C group – almost 200,000 eggs each as compared to 12,000.

Infected fish preferred warm waterThey also showed that once infected, the fish with infective worms preferred warmer water. A different population of infected and non-infected sticklebacks were introduced to an aquarium with cooler (~15°C) and warmer (~21°C) compartments, with an intermediate-temperature (~18°C) linking chamber. The fish were then allowed to settle in the intermediate chamber and watched for three hours.

The non-infected fish, as well as those with parasites too small to infect a bird, tended to stay in the intermediate chamber. However, fish with large, infective parasites preferred warmer waters, with a thermal preference over 1°C warmer than the other groups.

Although such a pattern might be perhaps be explained by an attempt on the part of the sticklebacks to increase the effectiveness of their immune system, the authors suggest that the tendency of fish bearing larger-but-noninfective parasites towards lower temperatures is more likely motivated by the tapeworms. Larger parasites would have increased energy demands, increasing the likelihood that the host would starve – and the parasites with it. When the parasites are large enough to infect a bird, however, all bets are off – the priority is to get large and to get eaten.

Previous studies on these species, such as Barber et. al. (2004), have found that, once a stickleback was infected by a sufficiently large parasite, the parasite would impair the fish’s abilities to flee predators. Fish infected by such parasites were less likely to make any evasive behaviour, less likely to reach cover, less likely to perform “staggered dashes” to prevent a predator from anticipating where they would move next and more likely to try and “evade” predation by simply slowly swimming away.

Fish that prefer warmer waters are probably going to end up at the surface and at the edges of lakes – right where they’d be more vulnerable to bird attacks. There is also potential for a positive feedback relationship – fish infected by larger parasites prefer warmer waters in which the parasites grow faster and the fish are more likely to be consumed by birds. It seems that one beneficiary of a warming climate is the tapeworms.

References

Macnab, V., & Barber, I. (2011). Some (worms) like it hot: fish parasites grow faster in warmer water, and alter host thermal preferences Global Change Biology DOI: 10.1111/j.1365-2486.2011.02595.x

Barber, I., Walker, P., & Svensson, P. (2004). Behavioural Responses to Simulated Avian Predation in Female Three Spined Sticklebacks: The Effect of Experimental Schistocephalus Solidus. Infections Behaviour, 141 (11), 1425-1440 DOI: 10.1163/1568539042948231 [PDF]

Other coverage

Some like it hot (if they’re riddled with parasites) – Not Exactly Rocket Science. Be sure to check out the comments, one of the authors has added information.

November 19, 2011 at 10:54 pm Comments (0)

Some videos whilst you wait

If only real deniers were capable of such introspection:

Hat-tip: Deltoid


Barry Bickmore on how he came to accept climate science:

Hat-tip: Class M

November 16, 2011 at 6:26 pm Comments (0)

Dr. Eugenie Scott on Evolution and Global Warming Denialism

Here’s a fantastic lecture from Dr. Eugenie Scott on the similarities of tactics and thinking between those who reject global warming and/or evolution:

HT: Greg Laden

September 28, 2011 at 9:13 pm Comments (0)

Photo #19 – Roboastra gracilis

Roboastra gracilis, a species of nudibranch
Roboastra gracilis, photographed in the waters off Pelorus Island, Queensland.

This photograph is a finalist in the Panda’s Thumb Photography Contest. If you’re interested in heading over there and voting for the best photograph – and I won’t blame you if you think it’s mine *hint hint* – then I won’t stop you.

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September 4, 2011 at 3:26 pm Comments (0)

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