Blinded by Science blog 9: How are Monarch Butterflies faring as a species?

Today’s blog post deals with a topic near and dear to all our hearts . . . bugs.  I know it is a topic that should lend itself to calm and quality discussion.

Or not.

Fine, we’ll focus on a cute, non-threatening insect.

You are not any of those three things.

I was talking about monarch butterflies.  Those pretty critters we all learned about in school.

See . . . it is cute, non-threatening and an insect.

Monarch butterflies are one of the most recognizable insects in North America with a very distinct orange and black pattern.  The butterfly has a four stage life-cycle: egg, larva, pupa, and adult.  Monarchs are a migratory species of butterfly, traveling in the fall from southern Canada and the northern United States to Mexico, a trip that is roughly 1,200 to 2,800 miles.  But over the last 20 years, monarch populations have decreased by about 90 percent.  And this leads us to today’s question.

Steve P. asks, “I know Monarch Butterfly populations have taken a big hit in the last few years.  What is the latest update?  What are the theories/reasons behind their decline?  Is there any hope that a sustainable population can be maintained?”

The biggest reason for the decline in Monarch population is habitat destruction in both Mexico and the United States.  In Mexico, to combat deforestation, the government in 1980 designated 56,000 hectacres of land as a wildlife refuge.  This refuge has since been called the Monarch Butterfly Biosphere Reserve and is now a UNESCO World Heritage Site.  Unfortunately illegal logging is still a problem.  Additionally, the land is also the home of multiple indigenous populations (most of whom are very poor) who, to make a living, use the forests in ways that harm the butterflies’ habitat (agriculture or logging).  As such, conservationists have begun working with these groups to incentivize them to take care of the Monarchs’ habitat.

In the United States, habitat destruction was a byproduct of new agricultural practices.  With the advent of genetically modified crops, specifically those that were engineered to be resistant to glyphosphate, the concomitant increase in pesticide use killed off native milkweed (the plant Monarchs lay their eggs on and the caterpillars feed on).  Without these plants, the Monarch butterfly populations dropped.

In a twist, recent efforts to plant milkweed to save monarchs appears to have backfired*.  As the article illustrates, people attempted to help by planting milkweed in their gardens at home.  Unfortunately, they planted the wrong species.  They planted a tropical species of milkweed, which in theory should not have mattered, but it did.  This species of milkweed did not die off in the winter months in the south like the native species would.  This caused two problems.  First, because it did not die off, Monarchs had no reason to continue their migration to the south and they ended up spending the winter in areas that they did not normally stay (though I could not find any information on whether this is a problem in and of itself).  However, it does directly lead to the second problem, parasites.  Milkweed hosts a parasite (Ophryocystis elektroscirrha) that is very debilitating to Monarchs, sapping them of energy to the point that they are unlikely to be able to make the full migration, dying along the way.

Normally, migration would “weed out” the infected butterflies so they do not pass the parasite on to their progeny.  Additionally, infected milkweed would die off during the winter months so when Monarchs return, they have a chance to use uninfected milkweed.  But because the tropical milkweed species doesn’t die off in the winter, Monarchs are staying put and getting infected with the parasite which is devastating to the already low Monarch population.

So what can be done to help?  The article points out that those who planted the tropical milkweed could remove it and plant a native species instead.  Or, if the native species is difficult to obtain, at least cut back the tropical plant every couple of weeks during the winter to encourage Monarchs to continue their migration south.  Also, the U.S. Fish & Wildlife Service is currently reviewing whether to list the Monarch butterfly under the Endangered Species Act.

So Steve P., there is definitely hope that a sustainable population can be maintained, which is good news for all the Lepidopterists out there (or anyone that likes to see the Monarchs migrate).

naturepl.com / Ingo Arndt / WWF-Canon

*The actual article is here but it is behind a paywall.

Blinded by Science blog 8: Why does the sun move?

Well folks, it was an incredibly stressful month of June and I was unable to complete a blog entry during that time.  For my readers (all 3 or 4 of you), I can only offer my apologies and tell you that it will never happen again.

REUTERS/Aaron Josefczyk

That’s how apologies work, right?

Anyway, in an effort to distract you all from the gaping hole that my lack of updating has caused in your lives, here is another question from my cute godson, G.  He asks, “Why does the sun move?”

Jeez, I cannot seem to get him off of this astronomy kick.  Is it too much to ask for some biology questions, things like, “Why are plants’ leaves green” or “Where do babies come from”?  Uhh . . . okay, you know what?  Let’s stick with astronomy for the time being, otherwise his mom might have a few “choice” words for me.

Well G, to answer your question, the sun does not actually move*.  It is actually the Earth that moves while the sun stays still.  When you asked why the sun doesn’t always shine, I told you that the Earth is really big and spins in space.  This means that the sun will shine on different places on Earth throughout the day.  If you remember, I had you perform a little activity to demonstrate.  Your mom stood behind you in a dark room and shined a flashlight at you.  As you stood in one spot and slowly turned to the left, the flashlight came into view (1).  As you continued to turn, you could soon see the entire flashlight (2).  And finally you would start to see less and less of the flashlight (3).

So because the Earth spins around in space, it seems that the sun is moving through the sky, but really the sun stays still.

*For those of you that aren’t three years old, my statement is not entirely true.

Hopefully this isn’t too obscure of a reference.

The sun does actually move.  It (and the entire solar system) revolves around the center of the Milky Way galaxy.  If an Earth year is the time the Earth takes to make one trip around the sun (365ish days), then a galactic year or cosmic year or whatever you want to call it takes roughly 230 million years.  Think of how few birthdays you would celebrate.

Blinded by Science blog 7: Do you really save any electricity and money by unplugging household devices when they are not in use?

Good day fellow humans.  It is I, your host, back for another tony edition of Blinded by Science.  And yes, you read that right, back for another TONY edition.  My name is actually an adjective meaning high-toned or stylish!  And as we all know, our names are permanent reminders used to fully describe who and what we are.

Who shall I be today?

Or not . . .

Anyway, today I will be answering a question from Steve P.  He asks, “Do you really save any electricity and money by unplugging household devices when they are not in use?”  Well Steve, this question reminds me of another question I have answered.  It turns out I was used as part of an ongoing marital argument when I answered that previous question so I hope that this is not the case now.  And if it is, I expect pay commiserate with the risk I am taking by getting involved.  I accept personal checks, cash, gift cards to delicious restaurants, and chocolate.

So now, let us get into today’s question.  Steve, the answer to your question is yes, unplugging electronics when they are not in use will save electricity and therefore money.  Though there is a caveat (when in life isn’t there?).  This only holds true for certain types of household devices – those that use standby power.  But what is standby power?  It is “electricity used by appliances and equipment while they are switched off or not performing their primary function.”  In other words, it is electricity that devices use when they are not in use.  Simple example, the little LED light on the front of the television that glows red when the TV is turned off (it changes color when you use the remote to turn the TV on).  It takes electricity for the light to be on, even though you have turned the TV off.  As another example, look at your microwave.  Even when the microwave is not in use, it uses electricity to keep the clock running.

The amount of electricity these appliances use is usually rather low.  According to studies done by Lawrence Berkeley National Laboratory, the majority of devices with standby power tested use less than 10 watts of electricity.  But having multiple devices in your home that use standby power can add up.

Let’s assume that the average device with standby power consumes 5 watts of electricity.  To convert that number into kilowatt hours (unit of energy consumption utilized by electric companies to determine cost) we must first multiply it by the number of hours that the device is on.  In one year there are roughly 8760 hours (24 x 365) that this device is drawing power.  So 5 x 8760 equals 43800 watt hours or 43.8 kilowatt hours.  The average price of residential electricity in the United States in March of 2015 is 12.35 cents per kilowatt hour.  So the average device with standby power costs a homeowner roughly $5.41 per year (43.8 kilowatt hours per year x 12.35 cents per kilowatt hour equals 540.93 cents per year).  That’s not too bad.  Unplugging this device permanently would basically allow you to have one more fast food dinner a year.  If the average house has forty of these devices, the cost then becomes roughly $216.37.  So unplugging these devices would save you quite a bit of money over the year which could be spent on other necessities.

Or a number of extra fast food meals

With that said, this only applies to devices that use standby power.  Electricity does not flow when an electrical circuit is not completed (think about how cars don’t move during a traffic jam because both lanes of a highway are blocked) so other devices, like lamps, that aren’t drawing electricity when turned off don’t need to be unplugged.  Also, you shouldn’t unplug all devices that use standby power either.  Refrigerators use standby power so they can continuously monitor the internal temperature and switch on when it gets to a certain point.  Unplugging a refrigerator would be a bad idea.

Nothing wrong here.  Just wipe it a bit and everything will be as good as new.  And delicious.

Well, I hope I’ve been able to help.  Tune in next time when I answer another of your burning science questions!

Blinded by Science blog 6: How can I trust that the information I am exposed to or gathering is accurate?

Welcome once again to another installment of Blinded by Science.  Today’s entry will have me answering two questions at once, not because of some silly notion of trying to work harder, but because the questions are so similar and therefore I’m hitting two birds with one stone (work smarter not harder).  Alicia E. asks, “Why can’t you believe everything you read on the Internet?  AKA What is peer-reviewed research and why is it important?  Please intersperse links to hilarious quacks peddling their conspiracy theories as science.”  In addition, Matthew L. asks, “There are so many ways to get information now a days, what is the best source and how do you know you’re getting the “correct” answers?  If I want to find an answer should I use Wikipedia, webMD, Google scholar or pubmed?  What makes them different anyways?”

Wow.  There are quite a few parts to each of those questions, but both basically boil down to “How can I trust that the information I am exposed to or gathering is accurate?”  This entry is especially important for me because I bet that I will soon be answering questions that deal with “controversial” topics and it will be nice to be able to refer to this post when questioned on my responses to those questions.  For this same reason, I’m going to try and keep this post as more “theoretical” and therefore not go into any specifics of “quacks peddling their conspiracy theories as science.”  As I said, not only will I will most likely end up mentioning these quacks in subsequent posts; I don’t want to give them any more traffic by linking to them if I can help it.  Heck, I’ll even try and keep this post serious.

So let’s get down to it.  How can you trust information presented to you?  While I will freely admit to being biased in this regard (it is important to keep in mind that being biased does not automatically mean I am wrong and it is always good to recognize when you are biased), if the information was generated through science, or cites scientific studies, you can feel good about it.

 

Okay, the seriousness didn’t last long.

Now before I get accosted by everyone, realize that my statement comes with an important caveat that I will be discussing a little further on, but for right now, please grant me a little leeway.

According to Dictionary.com, science is “systematic knowledge of the physical or material world gained through observation and experimentation.”  Science aims to answer questions about the physical universe and therefore increase our knowledge of it, usually via experiments.  I’m sure you all remember elementary/middle/high school science classes where you had to generate a hypothesis and then test it.  Well that is the most basic form of science and its most important aspect.  Anyone on the street can walk up to you and say that eating chocolate will cause your intestines to explode and kill you.

 

Would still be worth it.

But would you really take what they said at face value?  No.  And neither does science.  The claim that chocolate consumption causes death by intestinal explosion (hypothesis) would be tested.  Assuming the ethics of human experimentation wouldn’t have a problem with it, an easy test would be to give some people chocolate and see if more explosion deaths occur than in people to whom no chocolate was given.

But this brings me to the important caveat to my earlier statement.  Science does not work particularly fast, so it may take awhile to get at the answer.  One of the most important concepts in science is reproducibility, which is the idea that an experiment’s results, if done in the same way, can be reproduced by someone else.  It is part of the self-correcting nature of science, so if results cannot be duplicated then the results are called into question.  Additionally, the amount of subjects in the experiment is important due to concepts of probability (having more subjects involved helps to ensure that any results you are generating are due to your experiment and not merely based on chance).

Using the chocolate example from above, let us imagine a world in which you ran the experiment.  You enroll one volunteer and feed him/her a piece of chocolate.  Immediately, this person’s intestines explode.  Based on your experimental design (one person one piece of chocolate) you conclude that yes, chocolate does cause your intestines to explode.

You write up your results as a scientific paper and get it published (we will come back to this point later).  Others read the paper and wish to confirm your results.  They enroll one hundred people (Because let’s be honest, who wouldn’t join a study that was handing out free chocolate.  Also of note, it seems human subjects research laws are apparently ridiculously lax wherever these experiments are taking place).  This study also controls for other variables (like making sure no one ingests nitroglycerin during the study or eats chocolate made at a gunpowder factory).  All one hundred subjects eat the chocolate and are explosion free.  Now that there is disagreement in the literature, more experiments are done to try and confirm which side is correct.  All of these experiments, no explosions.  The consensus in the field becomes that chocolate is safe to eat.

Thank god!

But what about the original study, the one that had someone explode after eating chocolate?  It had some obvious experimental design problems that might explain the result being different from every other experiment.  The biggest problem was only having one subject in the study.  When you don’t have enough subjects in a study, the results you observe may just be due to random chance and not have anything to do with what you are studying.  This is why so many scientific papers utilize statistical tests to determine if their observations are real or just due to chance.  This is where the term “significant” as it applies to science comes from because it means something slightly different than its “real-life” definition (contrast definition 1 with definition 3).  Results are considered significant if, and only if, they pass statistical muster and are therefore determined to not be due to random chance.  Again, this does not mean the results are large or important.  But then, how do we know if studies published are designed appropriately?  Science has a system in which other scientists review your work before it can be published, checking for design or interpretation flaws.  This “peer-review” system works rather well and certainly catches a lot of the most egregious problems (sorry, egregious is such a fun word to use that I had to use it).  But it isn’t perfect, which is why reproducibility is such an important part of science as well.  Reproducibility helps to catch scientific fraud or methodological mistakes because if results are not able to be repeated, the community takes a harder look at the methodology utilized.

But what the heck does this all mean for the original questions of this post?  It means science is really good at catching its own mistakes and is self-correcting, though sometimes this process can take a long time (it takes time for further studies to be published or for better technology to be developed that allows for better experimental design).  As such, on the internet and in life, you should just trust me for your informational needs.

I am not a crook.

Seriously though, where the internet is concerned, information you find on sites like PubMed.gov and Google scholar are usually very trustworthy.  They only contain articles that have been peer-reviewed and published in academic journals.  But they are databases of articles so it can be hard to find the specific information you want.  Sites like Wikipedia make it easier to find the information that you want and are usually very trustworthy when it comes to facts (especially because they have to cite their sources), because it is possible for pretty much anyone to edit the content, you need to be more skeptical of interpretations based on these facts or opinions expressed as facts.

So what should you be most skeptical of when it comes to the information presented to you?

1) Articles that cite only one study and give it outlandish claims (especially if this is a recent study):  News articles do this all the time.  They blow a study’s conclusions way out of proportion.  As an example, imagine a paper that observed cancer cells had a defect in glucose metabolism that made them unable to survive without an adequate supply.  In the discussion, the researchers mention that perhaps decreasing dietary glucose could help treat cancer patients.  News sites, in an effort to generate hits, would create headlines like “Study says sugar causes cancer!” or “Study says low-glucose diet cures cancer!”  That’s why it is always better to actually read the source if you can.  Plus, as I said above, until a study’s results have been reproduced, also treat them with a grain of salt.

2)  Anecdotal evidence (personal stories):  I’ve seen this online constantly where a website or poster in the comments section (by the way, reading comments sections is possibly the quickest way to lose all faith in humanity whatsoever and yet, despite knowing this, you are never able to stop) posts a personal story either about themselves, their immediate family members, or friends (anti-vaccine being the most common I’ve come across, but many others refer to anecdotal evidence as well).

But anecdotal evidence is ABSOLUTELY TERRIBLE for coming to any sort of conclusion about anything*.  There are no statistics involved and no control of possible confounding variables.  Random chance happens.  Just because your significant other broke out in acne all over his/her body two hours after eating peanut butter ice cream does not mean ice cream causes acne.  That was an awful thing to have happen, but it would be irresponsible (at best) to immediately blame it on the ice cream.  It could have just been a freak occurrence or it could have been the new body soap he/she used in the shower that morning.  The point is, until the situation is systematically studied, you just can’t know for sure what the cause was and that is why you have to be extremely skeptical about anecdotal stories.

I’d like to end this post with a little warning to everyone that looks up information online, reads the newspaper, or watches the news on TV:  Beware of confirmation bias.  Confirmation bias is the unconscious tendency to believe information which agrees with or reinforces your previously held ideas and to reject that information that disagrees.  Someone who already thinks ice cream is bad for you would be much more likely to take the story of ice cream causing acne as truth and less likely to believe someone who argues that ice cream couldn’t cause acne, even if that second person had evidence.  So always be on guard when presented with new information so you can evaluate it fairly and please keep in mind any biases you might have (because we all have them) so as to not disregard good information just because it calls into question a belief you already had.

*Anecdotal evidence can provide rationale for scientific studies on the subject, but taken alone, this type of evidence means nothing.