"Did you know?"

Monday, March 30, 2009 at 9:44 PM Bookmark and Share
Some nice food for thought from Karl Fisch and Scott McLeod (with some help from the visual design company XPLANE). Also, have a look at some of the video authors' comments on the challenges and importance of technology education at their websites (linked above).

Educators should pay particularly close attention starting around 6:40!!!



Other information at ShiftHappens.

Not exactly certain of the origin of this next version, but it too is worth a look:

More from the Texas Board of Education

Sunday, March 29, 2009 at 5:41 PM Bookmark and Share
The State Board of Education Chair, Don McLeroy (who believes in intelligent design / creationism and takes issue with evolutionary theory) provides us a nice glimpse into what scientists and educators are up against in Texas: passionate adherence to amazingly incorrect ideas about evolution. The Texas Freedom Network has nice coverage and commentary from the board meetings, including this clip of McLeroy showing his lack of scientific understanding:



If you don't already recognize the numerous errors in his arguments in the clip, I'd encourage you to look into some of his claims. Corrections to his flawed arguments can probably be found on the web with minimal effort (e.g. using google or Wikipedia).

Links:

More from the Texas Freedom Network.

More on McLeroy's actions as part of the state board of education.

"McLeroy, Confused Again" Texas Citizens for Science, March 14 2009.

"McLeroy Shows His Ignorance of Evolution" ScienceBlogs, Ed Brayton.

Attack on evolution continues in Texas

Thursday, March 26, 2009 at 5:42 PM Bookmark and Share
Today, all eyes were on Texas where anti-evolution proponents nearly succeeded in their efforts to attack the teaching of scientific theories (namely, evolution) in public classrooms. Fortunately, the outcome went in favor of the pro-science and pro-education camp (though it was a very narrow win).

I highly recommend reading through some of the actual panel discussions, for example some highlights can be found on the blog Thoughts from Kansas, by Joshua Rosenau at Scienceblogs.com.

In a vote to restore subtle yet damaging anti-evolution language to the state's science curriculum rules (language that was recently pulled out of the rules by the board) the board voted in a 7-7 tie (7 Republican for the language, 3 Republican and 4 Democrats against), casting out the language (for now). For more details, see this piece by The Dallas Morning News.


The Peppered Moth (Biston betularia) - A classic example of observable microevolution, though often misused by young earth creationists in their claims that evolution doesn't lead to different "kinds" of organisms. The overwhelming body of evidence supporting the theory of evolution (it seems) will never satisfy young earth creationists. They only seek to support their beliefs and not to use science to understand natural processes like macroevolution.



Thankfully, many state and national scientists, science educators, and related organizations have been sharing their concerns and expertise with the board - pointing out where anti-evolution proponents are trying to pull a fast one and emphasizing the importance of a solid science curriculum free of political and religious tampering. Even some of the state's religious leaders are speaking out in defense of evolution.

Letters from various organizations can be found here.

The final vote on the curriculum will take place tomorrow (March 27, 2009).

More at these related links:

Baptist Press
National Center for Science Education
ScienceBlogs - Josh Rosenau
More from Josh Rosenau's coverage of the board meeting
Texas Observer (blog)
The Clergy Letter Project.
Science, Evolution and Creationism - a fantastic (and free!) electronic book by the National Academy of Sciences.

Black Market Wildlife: Who Cares!?

 at 12:19 AM Bookmark and Share
Hopefully you do, and if you don't - let me explain why you should.

First, here is a press release from the New York Department of Environmental Conservation on a recent progress to stop the illegal trading of native reptiles and amphibians from New York state and nearby areas.

So why is the illegal trade of wild animals such a big concern? Not surprisingly, there are lots of reasons.

Lets begin with the most obvious reason: to ensure the health and persistence of existing wild populations. The demand for many wildlife species for food, pets, and/or for traditional "medicines" has lead to the drastic reduction in wild populations worldwide. There are countless examples of this happening all over the world. For example take the story of the Spix's Macaw (Wikipedia | birdlife.org) which went extinct in the wild in 2000.

For other examples, you can read more here from NPR and here at america.gov. To make a long story short - we humans do a pretty good job of wiping out wildlife unless we practice some restraint!

So what's our secret to being such efficient exterminators? Going back to the recent arrests in New York state, it's worth mentioning that these collectors endanger wild populations on a number of levels. The obvious harm comes from the removal of individuals from sensitive populations, which can lead to significant and long-lasting population declines. This is what we usually think of as the main problem. Additionally, however, the destruction of local habitat can also have a lasting negative impact on wild populations: see the results of this study for an example. Unfortunately, this fits a general pattern: overharvesting wild populations while at the same time reducing high quality habitat seems to be a great recipe for decimating a species.

Some people, perhaps you yourself, don't find this all that big of a problem - "so a few species go extinct - big deal!" Arguments against this sentiment can be found here and here, so I'll leave that issue alone for now. But even from this very extreme perspective, there is still more to be concerned about beyond species conservation alone!

Other big reasons to keep tabs on the trade of wildlife (reasons often overlooked in the public eye) are concerns about spreading disease and invasive species.

Wildlife can carry diseases that can be harmful to humans, livestock, and/or to the wildlife in other regions. Illegal trade in wildlife has a huge potential for the spread of costly diseases at a global scale - for example consider the recent worry about the global spread of bird flu, and the fact that SARS originated in bats or other wildlife before infecting humans. For more on wildlife and disease concerns, see this article and some of the other information from the U.S. Centers for Disease Control and Prevention (CDC).

Invasive species can also cause a great deal of environmental, agricultural and economic damage, for examples see the impact of invasive species and check out the relatively new (2005) government website for the NISIC. For more on the invasive species side of the illegal trade in wildlife, check out the (more comical) hippos in Columbia, or the information available here.

Killing the competition: Cormorants

Tuesday, March 17, 2009 at 2:11 PM Bookmark and Share
Today I came across a nice overview of the current problems surrounding Cormorants and the push to kill off large numbers to maintain or increase fishing yields. The article appeared as this months Natural History Magazine's featured article "To Kill a Cormorant" by Richard J. King.


If you haven't heard of this little conflict before, check out this New York Times article from 1998: The Slaughter of Cormorants in Angler Country. For a closer look at a Cormorant, click here, here, and especially here.

Why the conflict? The main causes are aesthetics and good ol' interspecific competition for resources - one of the big claims is that Double-crested Cormorants deplete populations of game fish. The validity of this claim is somewhat of a mixed bag: Cormorants indeed cause declines in commercial fish farms where fish are accessible and at high densities. In wild settings however, evidence is weak and their impact on fish populations seems to depend on the location and the fish species in question.

Competition for fish aside, Cormorants can also trash the small islands they decide to turn into breeding sites via a build-up of guano, which like most bird droppings is high in uric acid (the white stuff). This kills off vegetation, giving the combined result that these islands are as unpleasant to look at as it is to be downwind of them. As Richard King points out, historically those islands may have actually hosted Cormorants and their guano more so than the vegetation that took their place when Cormorant numbers dipped during the last couple of centuries. They can also compete for nest sites with various species of Herons and Egrets. This all adds up to a big public image problem - people don't like things that ruin scenic landscapes and push out more valued species.

So do Cormorants need to be controlled? Practically speaking, probably yes - but only in a few places, and hopefully with smarter controls than poorly regulated mass culling.

Are we going to avoid continuing on a "witch hunt" blaming these birds for our fisheries problems, or instead use good science to get at the root of this conflict? With the usual amount of patience and compromise, it seems a workable science based solution is quite possible.

In their Notice of Intent to Prepare a National Management Plan for Double-Crested Cormorants the US Fish and Wildlife Service (USFWS) mentions a court challenge against the USFWS for issuing permits to oil eggs in up to 10,500 Cormorant nests at two locations in the north east. Referring to that legal action, they go on to say that:
... the action highlights the need for scientific inquiry into the nature of the problems caused by double-crested Cormorants and an assessment of the utility of management actions most likely to resolve resulting conflicts.
By studying fish populations and the role Cormorants play in regulating them, along with the other problems caused by Cormorants, regulatory agencies can make effective and efficient management plans where necessary. Just as importantly, if not more so, the results of these studies will hopefully help the public to distinguish fact from fiction when it comes to Cormorants - good for the birds, and good for the people.

Related links:
  • The USFWS Double-crested Cormorant page. Includes their final Environmental Impact Statement, which is worth skimming.
  • EPA website search results.
  • Derby and Lovvorn, Canadian Journal of Acquatic Science, 1997. Some might take this as evidence against Cormorants - but based only on the abstract it appears to conclude little more than They ate a lot of the fish we put in the river. This, is what you'd expect: Cormorants eat fish. This may be a good study to look at stocking efficiency, but for our purposes the important question is what is the impact on the fish population?
  • That question is addressed, for example, in Engström, Ecography, 2009. The result? Despite large rates of consumption by Cormorants, there was no significant effect on the fish population.
  • To contrast, here is some commentary on a study showing Cormorants can impact some fish populations (Perch, in parts of Lake Huron).
  • Google scholar results for "cormorant fish".

More on vaccination and science literacy

Sunday, March 15, 2009 at 1:24 PM Bookmark and Share
I just ran across a post to the blog Sandwalk, that points out the role of journalists and scientists in helping the public make informed decisions when it comes to their health. Have a look at this video (embedded below) from this post by Dr. Ben Goldacre to his blog Bad Science.

Experiments, Mathematics and Theory in Ecology

Friday, March 13, 2009 at 9:50 PM Bookmark and Share
If you check wikipedia or dust off your favorite dictionary and look up the definition of "ecology" you will find something like the following:
Ecology: The branch of biology concerned with the relations between organisms and their environment.
As a branch of biology, and thus a science, you might think that ecologists have centuries old traditions (much like physicists and chemists) - doing controlled experiments in their laboratories or gardens and using the scientific method to test hypotheses and formulate scientific theories. Right?

Well, not quite. History tells us almost the opposite has been the case up until recently... very recently, come to think of it!

I had originally set out to write a single piece, but it got a bit long so I've split it into two parts: the first basically revisits the recent conversation (from the course I TA) that prompted all this, and the second is a bit of a followup heavily seasoned with a few tangents that are likely of interest.

Earlier this week in class, a friend of mine raised a question in class that caught me a little off guard. It made me realized something I had taken overlooked or granted during the past decade or two of my science education: only very, VERY recently did we begin to develop a real understanding of how organisms interact with (and respond to) the world around them. The same could probably be said of knowledge about the natural world!

But on to our example. In lecture this week (for the course "Theoretical Ecology"), we discussed some really nice work that included research done by Dr. Jef Huismann and others, currently at the Institute for Biodiversity and Ecosystem Dynamics at the University of Amsterdam.

During the hot summer months, a lake used for recreation near Amsterdam turns into a smelly, stagnant health hazard due to blooms of toxic cyanobacteria. Understandably, local parks officials wanted to find a way to continue recreational use of this increasingly smelly and toxic body of water without the drastic measures require to stop the actual problem of nutrient pollution (e.g. fertalizers) in the lake.

His group used very controlled laboratory experiments in conjunction with mathematical models of those experimental systems to understand how mixing patterns in water (e.g. due to temperature gradients) influence competition for light among different types of algae under controlled laboratory conditions (think little green beakers). These factors are known to shape the types and numbers of algae you see in small ponds and lakes, and presumably play a role in our lake. (For the philosophically inclined reader, this is using good ol' scientific reductionism being used to lay a conceptual foundation.)

Results from those small scale experiments were then combined with more complicated computer models of the hydrodynamics of an actual lake in order to understand how mixing could be used to control the algal community residing there. With that, they were able to use the models to see how different ways of artificially changing the hydrodynamics in the lake might provide a solution to the problem.

So what was the solution? Based on all the modeling and experimental work, it turned out that a little extra mixing in the right places would cause the good algae to replace the bad. With a few properly placed pumps to bubble the lake, it was returned to its more recreation-friendly state. (More details can be found in Jef's scientific papers, and also in Chapter 7 of the book Harmful Cyanobacteria - if you're interested.)

Along with the many other scientific details uncovered along the way, this is a really cool example of using experimental findings in conjunction with mathematical and/or computer models in order to do exemplary scientific work. The models extend our reasoning and deductive abilities and combined with nice experimental results, lead to a deeper understanding of how algal communities form in these sorts of ponds and lakes.

Much as mathematical models helped Newton understand and describe the laws of motion, Huismann and many other modern day ecologists use similar mathematical models to describe and make predictions about biological systems. But if the math is so similar, why weren't Newton's biologist friends (or at least their grandchildren) doing the same sorts of thing back in the 1700s?? What's so different now that we had to wait 200 years for in order to apply these techniques to biological systems the way Newton and his colleagues applied them to planetary motion?

After the instructor finished talking about Huismann's work (and some of its more technical details), a friend of mine raised his and asked essentially this question: Why didn't someone do this 50 years ago?? It seems so... rudimentary!

Naturally, we looked to the instructor anticipating his response, which was essentially this: Physicists have been using experiments and models to understand and describe natural processes since Galileo (around 1600) - Ecologists (and their biologist and other predecessors) have only been doing it since the early 1900s or later. It just took that long for folks to embrace the idea of doing experiments and using mathematics understand and describe the natural phenomena being observed.

This, admittedly, caught me a little off-guard. I'm sure my thoughts were something like "Wait, what? But, why!?" But in truth, it is an interesting question: why has it taken so long for some of the sciences to gain prominence in recent centuries and (more generally) throughout human history? What walls were broken down recently that unleashed the flood of scientific inquiry we see today?

Well, there are of course a number of ways to answer these questions - certainly many more than I am aware of. Still, I can point to a few of them. Check back for part II of this post in the next couple of days, where I'll try to address some of them.

Why some love - or hate - Coriander

Wednesday, March 11, 2009 at 1:05 AM Bookmark and Share
Opinions are quite varied on whether adding fresh coriander (aka cilantro) to a recipe makes or breaks the dish. Some folks simply love the stuff while others find the herb quite repulsive - often noting a metallic, soapy or otherwise unpleasant flavor (other descriptions of the repulsive taste and/or smell can be found here) a description that seems quite different from how fans describe it. So why the disparity??

Thanks to work by a few diligent and inquisitive scientists, we do know a few things about this love-hate relationship with one of my favorite herbs. Some these discoveries have been stumbled upon while working on more important issues while others come more focused and direct studies of the plant.

Coriander (aka cilantro or Chinese parsely) is the common name of the plant Coriandrum sativum, a member of the carrot family Apiaceae or Umbelliferae. The young leaves are the herb called cilantro, while the older leaves and seeds are called coriander - although the herb is commonly referred to by both names. For some interesting Coriandrum chemistry, check out the chapter on the chemical properties of the herb starting on page 190 of Chemistry of Spices, available through Google Book Search. Unfortunately the book doesn't have much info on why some find the herb so revolting...

So why the divide? According to work by folks like Charles Wysocki from the Monell Chemical Senses Center it seems there are very likely some genetic factors that contribute to the preference. This based on preliminary work comparing pairs of twins with non-twins - if its heritable, pairs of identical twins will share a preference more so than fraternal twins, with the lowest proportion of shared preferences seen between non-twin siblings.

Initially some believed the cilantrophiles among us were unable to taste or smell some particularly offensive chemical found in the plant. This is a reasonable hypothesis, and is in line with similar phenomena such as the more common example involving asparagus (although I recently learned that producing and being able to smell the offending byproduct in this case are two separate issues).

With cilantro, it turns out this notion is a bit off. There does seem to be a difference in smelling (and tasting) ability among the cilantro lovers and haters among us, but according to this essay by Josh Kurz on the NPR website, the smell some folks are missing out on is not a foul one, but that pungent lemony smell so adored by cilantro lovers. If you are among those who hate cilantro, you really might not know what you're missing!

Given the descriptions I have heard and read, there may indeed be some other more unpleasant smells that are only detectable by the unfortunate few. This could simply be because the compounds that smell so good to some are themselves the culprits, being pleasant to some and repulsive to others. The GC anecdote in Josh Kurz's article suggests otherwise, however. So the two smells/tastes are indeed caused by two different chemicals. Unfortunately the essay doesn't mention whether or not researchers Wysocki and Preti were also able to smell the unpleasant compounds.

Interestingly, this information doesn't show up on ihatecilantro.com!

So will the world be a better place for knowing all this? Probably not, but I can already imagine someone slaving away for Monsanto trying to get rid of the repulsive compounds - after all, there is a big difference between "tastes bad" and "tasteless"!

Obama to Ease Limitations on Stem Cell Research

Sunday, March 8, 2009 at 11:11 PM Bookmark and Share
Tomorrow, President Obama plans to remove some of the limitations on stem cell research that were put in place by former president Bush. No doubt there will be a lot of news about it this week - but why all the fuss?!?

Let me begin by pointing out that there are many ethical (and unethical) ways to obtain and do medical research using human stem cells. Fortunately, we have people trained to wrestle with these issues (i.e. people in the fields of medical ethics and bioethics), lots of government and public oversight of this area of research, and a plethora of "watch dog" groups making sure no lines are crossed.

Unfortunately, for those who look only to their faith when it comes to questions of morality, we don't have a few thousand years of people asking the question "Is it good or bad to kill a recently fertilized oocyte?" So we look instead to the answer to the next best question: "Is it good or bad to kill human life?" This has a more clear answer, although this where the trouble starts - people have a lot of different of ideas about what "human life" means in this context.

I'll post more on this subject this week as events unfold, so for now I'll stick to my original question: why all the fuss?!

First, the general public seems to have a poor understanding of the exact nature of these limitations. I can only hope that the media, cultural and religious leaders, the scientific community, the bioethics community and the White House will do a good job of clarifying some of these details for the public.

Second, some individuals and other entities (e.g. certain extremist religious and political figures) use such controversies to try and sway the public in favor of their agendas. This has the unfortunate effect of making it to their benefit to misinform and mislead the public to those ends. Look for it this week - I'm sure there will be plenty of examples!

For more information, see the links at the bottom of this new story and my posts later this week.

Political (errr..... visual?) Instincts

Tuesday, March 3, 2009 at 7:34 PM Bookmark and Share
Here's a little news short from ScienceNOW on some recent work showing how children are just as swayed by looks as adults when it comes to choosing candidates for political office.

I thought it might lighten the mood a bit after all those vaccination posts!