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The Butterfly Effect

Chaos exampleThe other day in the car my children asked me to explain the difference between Chaos Theory and the Butterfly Effect. Questions like this are not uncommon in my family. I thought about it for a moment and realized I did not know the answer, a circumstance that I do not enjoy. So children and readers, here is the answer.

For a system to exhibit “chaos” as defined by physicists, four elements must be present. First let me list them. Then, to best of my ability, I will attempt to explain their significance. However, I must warn you that as we proceed down the list my explanations will become increasingly inept.

  1. The system must be deterministic.
  2. The behavior of the system must be very sensitive to initial conditions.
  3. The system must be topologically mixing.
  4. The system must have periodic orbits which are dense.

 

The first element tells us that once the initial conditions of a system are determined, the behavior of the system is also determined. Therefore, if we can reproduce the exact initial conditions, we will get the same outcome every time. This introduces you to a key point about chaotic systems, their behavior is not random.

The most dramatic aspect of chaotic systems is element number two, that small changes in initial conditions can result in big changes in the outcome. The picture at the top of the page shows a simple example of this. Let’s say that you try to place the purple ball right on the very peak of the rainbow colored shape. A very small change in the initial position of the ball can result in it rolling down an entirely different side of the hill. However, if you were successful in placing the ball in exactly the same spot each time, it would always roll down the same path, which is what makes this system deterministic rather than random. What gives chaotic systems the illusion of randomness is that recreating initial conditions exactly is very difficult. You may think that you are putting the purple ball in the same place each time, but actually you are not.

Once we get to element three my understanding starts to get a little murky. I don’t really understand the significance of the word “topologically” in this one. In layman’s terms, a chaotic system must be mixed. Examples include air and water molecules in a weather system, or the movement of food dye in a glass of water.

To understand element four, you need to understand the mathematics of field theory and phase space. Sadly (or perhaps happily) I don’t, so we’ll need to agree to remain entirely in the dark on this one. Any mathematicians or physicists reading this who want to help out, please use the comment space below.

The father of Chaos Theory was Edward Lorenz, a professor of meteorology and mathematics at MIT. In 1963, he was doing some weather calculations in which one of the parameters was 0.506127. The computer came up with an answer but, to be thorough, Lorenz wanted to run the program a second time to reproduce the result. Either he was in a rush or his fingers were tired so this time he rounded the parameter to 0.506 and the calculations came up with a dramatically different answer. This observation led him on a decades long quest to further explore these types of phenomena, during which he wrote a series of research papers which came to define Chaos Theory.

Just like me, Lorenz found the second element to be the easiest to explain. The first example that he used was “if a seagull flaps its wings in Tokyo it could eventually cause a hurricane in New York”. Fortunately, someone with a better ear for marketing encouraged him to use the more compelling image of a butterfly, giving birth to the Butterfly Effect.

This brings us to the answer to my children’s question. The Butterfly Effect is a subset of Chaos Theory, fulfilling elements one and two above, but not necessarily three and four. Therefore, all chaotic systems exhibit the Butterfly Effect but not all systems which exhibit the Butterfly Effect are chaotic. Not the most exciting answer in the world, but, hey, I do my best.

Have a comment or question? Use the interface below or send me an email to commonscience@chapelboro.com.

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Could Caesar Eat Peanuts?

I recently had the chance to read through my stack of the last several months of Scientific American® magazine. My curiosity was piqued a story in one of the issues about a study conducted by the Henry Ford Hospital in Detroit. The study reported that babies who had been born via Caesarian section (C-section) were five times more likely to develop food allergies than those born vaginally. Like many parents I know, I have a strong impression that childhood food allergies are far more prevalent now than in the 1970s when I grew up. I have no childhood memories of peanut-free classrooms or EpiPens.

A search of the CDC and NIH websites provided the data for the graph below.

casarian data

C-section rates have been steadily rising in the United States, from around 5% of births in 1970 to nearly 33% today. The data for childhood peanut and overall food allergies show that not only are childhood food allergies on the rise, but the rate of rise is nearly identical to the rate of increase of C-sections.

We’ll get back to the correlation been allergies and C-sections in a moment, but first permit me a brief aside to do a little math. I read several news reports on the Henry Ford Hospital study which all included the “five times more likely” statement, but omitted any absolute numbers. This is a key gap. For example, if C-sections increased the chance of developing a food allergy from 0.01% to 0.05%, it would probably not be significant enough to factor childbirth decisions.

However, using the data from the graph above and little algebra, it is not difficult to quantify the risks. If the 33% of children born via C-section are five times more likely to develop food allergies, and the total rate of allergies for all children is 5.1%, then the chance that a child born by C-section will develop a food allergy is 11.0% versus just 2.2% for a child born vaginally. This is a noteworthy difference and likely worthy of some consideration by expectant parents.

Getting back to the graph, we can see that childhood food allergies and rates of Caesarian births are closely correlated, but correlation does not necessarily demonstrate causation. The study at the Henry Ford Hospital addressed this issue and developed a convincing case for causation. While in-utero, the gastrointestinal (GI) tract of a child is bacteria free. Beneficial bacteria in your GI tract are essential both to digest food and to ward of disease. Therefore, newborn babies need to rapidly develop a large and diverse population GI tract bacteria.

During a vaginal birth, the baby’s GI tract becomes populated with the mother’s bacteria from the ingestion of fluids through the mouth. This “inoculation” of bacteria from the mother gives the child a tremendous head start towards developing a healthy digestive system. Babies born by C-section only start to populate their GI tract with bacteria from breast milk and/or from sticking their fingers in their mouths. This less efficient approach to establishing a healthy bacteria population appears to dramatically increase the incidence of food allergies. Food allergies may lack a scary-sounding name, but they are by no means a trivial circumstance. Sufferers can experience reduced quality of life, severe reactions, and, in extreme cases, death.

The parallels between this column and the issues I discussed in my recent column entitled “The Perils of a Hyper Hygienic Existence” are striking. Through the use of antibiotics some people have the population of healthy bacteria in their GI tract dramatically reduced in a sustained manner. This circumstance can bring about debilitating diarrhea and a variety of other serious GI tract problems. Recent studies have shown that these patients can experience remarkable improvement by introducing the bacterial flora from a healthy donor by a process rather unfortunately named fecal transplant.

When considering the correlation between Caesarian birth rates and food allergies I thought a similar solution might be appropriate. When Caesarian births are performed, I thought that a methodology might be considered which would introduce the mother’s bacterial flora to the child’s GI tract to help fend off food allergies.  I found a recent study conducted in Venezuela which did just that. They gave the child the bacteria she needed with a simple mouth swab after the C-section. This simple procedure could dramatically reduce the incidence of food allergies in C-section babies.

Have a comment or question? Use the comment interface below or send me an email to commonscience@chapelboro.com.

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The Caterpillar Effect

buckeye butterfly Last week my wife and I were in St. Martin and went to a butterfly farm where I learned something new. Something I feel like I should have already known. I have long been aware that butterflies have been declining in numbers due to loss of habitat and the use of pesticides. Over the years, both in my own yard as well as at some property I own west of Carrboro, I have been attempting to be helpful to butterflies by planting zinnias, butterfly bushes and other flowering plants. While at the butterfly farm I learned that I had been ignoring the needs of caterpillars, and that looking after the caterpillars was the part that really mattered. Reviewing the amazing life cycle of the butterfly makes this point quite clear.

Before we proceed, let’s review some of the key butterfly facts and figures.

  • Butterflies have been around for 40 to 50 million years.
  • Butterflies live on every continent except for Antarctica. Approximately 700 species of butterflies live in the United States.
  • Although less efficient than the honey bee, butterflies play a very important role as pollinators for human food crops.
  • They are also quite beautiful. The photo at the top of the page is a Buckeye butterfly taken at my Orange County property.


Let’s begin our review of the life cycle of the butterfly, starting with an adult female. Not long after spreading her wings for her first flight she will identify a mating partner. For some species of butterflies this involves an intricate mating ritual in which several males will compete for her attention. In other circumstances the males’ behavior is far less chivalrous and the viewpoint of the female is not taken into consideration. Once the mating pair as been determined, the interlude continues for approximately 48 hours. (Early drafts of this column included a number of jokes at this point that I thought to be rather clever, all of which, after a more prudent review, I decided to omit.)

Depending on the species, a female butterfly lives from 1 week to 9 months. During this time she will feed on nectar from flowers and lay her eggs, but in a very particular way. As I learned during my trip to the butterfly farm, once the eggs hatch into caterpillars, many species can only eat the leaves of a single plant. Therefore, the butterfly must lay her eggs on that particular plant for the caterpillars to survive and produce the next generation.

The moment I learned this, the inadequacy of my butterfly gardening efforts over the last several decades became clear. Sure, I had provided good sources of nectar for the butterflies to eat, but hadn’t given them a place to lay their eggs. This turns out to be a fairly major flaw. The decline of the butterfly population is driven much more strongly by the dearth of caterpillar host plants than a lack of flowers for the adults to feed from.

Caterpillars live for about two to three weeks, during which they eat and grow very, very rapidly. Once a caterpillar reaches a sufficient size, it selects the underside of a branch and weaves a small silk pad. The caterpillar is equipped with a small hook-like appendage called a cremaster which allows it to hang upside down from the silk pad. Then it sheds its skin to reveal a chrysalis, the hard shell which protects the growing butterfly, which it has already made from its own body.

One to two weeks later a butterfly will emerge, but not before one of the most amazing biologic processes on earth occurs. Inside the chrysalis, the body of the caterpillar complete breaks down to form a liquid consisting of undifferentiated cells called imaginal cells. These are akin to stem cells in humans and can be converted into any type of cell for the developing butterfly. As I sit back and consider the complexity of this transformation, I am awestruck. For me, it provides some additional insight into the power and pace of evolution. Butterflies have been perfecting their genetics and life cycle for 50 million years, ten times longer than the 5 million years that hominids have walked the earth. Consider what changes in human biology could occur in the next 45 million years if we manage to hold on that long.

In the meantime, I have been engaged in a total overhaul of my butterfly gardens to include caterpillar host plants. You can get more information on North Carolina butterflies and caterpillars on www.naba.org. In the meantime, next time you are planting please consider.

  • tulip trees
  • sassafrass
  • wintercress
  • clover
  • alfalfa
  • dill
  • parsley
  • blueberries
  • viburnum
  • asters
  • milkweed
  • wisteria

The caterpillars, and butterflies, will be happy.

Have a comment or question? Use the interface below or send an email to commonscience@chapelboro.com.

http://chapelboro.com/columns/common-science/the-caterpillar-effect/

Something is Rotten in the Province of Alberta

2986100971_e1faba0513_zScheduling conflicts this week have prevented me from putting together a full analysis of the topic for this week’s column. I will provide more details in the future, but for the time being, I wanted to apprise you of some troubling events in the Alberta Oil Sands.

The oil sands in Alberta are pretty much what they sound like, oil mixed with sand and a variety of other impurities, many of which are both difficult to remove and toxic. Compared to a traditional oil field, the hydrocarbons in Alberta, referred to as bitumen, are larger and have longer molecular chains, which cause the bitumen to exist as a solid rather than a liquid at ambient temperatures. In order for bitumen to become liquid enough to flow through pumps and pipelines it must be subjected to some combination of heating, dilution with lower molecular weight hydrocarbons, and/or chemical processing, to break the large molecules into smaller ones. When dilution, the most common approach, is used, the resulting material is called “dilbit” for diluted bitumen.

Bitumen is extracted from the ground in two ways. The material nearest to the surface is strip mined. In this technique, the earth, sand, and bitumen is excavated, put into the largest dump trucks ever built by mankind, and moved to a processing facility. About 20% of Alberta’s oil sands can be excavated by strip mining.

The other 80% of the bitumen is buried too deeply to be strip mined, so the oil companies plan to recover this material by injecting high-pressure steam several hundred feet into the ground to melt the bitumen and then allow it to flow back up to the surface through the same pipes used for the steam injection. This type of processing has been given a number of different Orwellian-sounding names. I’ll call it in-situ processing for the remainder of this column. In-situ processing has been demonstrated to be feasible on the small scale. Now that much of the shallow bitumen has been excavated via strip mining, oil companies are beginning to attempt in-situ processing on a large scale.

The scale-up of in-situ processing, to be diplomatic, is not off to a good start. The near surface zones where in-situ processing is practices contains relatively soft and porous geologic formations. When melted and pressured in this environment, the bitumen is not demonstrating any particular compunction to restrict its movement to within the pipes, as intended by the oil companies. It is flowing to the surface through cracks and porous materials and seeping into adjacent underground aquifers.

An uncontrolled excursion such as what I described above has been ongoing in Cold Lake, Alberta since late May. Once the bitumen has been heated and pressurized, there is little that can be done to mitigate the situation. The full environmental impact will not be known for some time. My instincts tell me that this type of event will become quite common if in-situ processing is applied on a large scale.

I have decided that from now on, any time I write a column on fossil fuels or climate change, that I will close by reminding you of the most important part of the story. Humans have already raised the carbon dioxide concentration in the atmosphere to 400 parts per million (ppm), a level 33% higher than it has been during the last half a billion years. At 400 ppm we are already experiencing changes in our climate which threaten our well being. Climate scientists predict that an atmospheric carbon dioxide concentration of 450 ppm represents a tipping point for the climate, at which point serious damage will occur to human civilization. Remaining below 450 ppm will require that we leave over half all currently-know fossil fuel reserves in the ground, forever. There is likely no better candidate to be left in the ground that the bitumen deposits in Alberta, yet we continue to scratch and claw them from the earth, even it if means turning Northern Alberta into a toxic wasteland.

Have a comment or question? Use the interface below or send me an email to commonscience@chapelboro.com.

image by pembina.institute

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Monkey Pox … Seriously ?!

Analysis of ancient skeletons tells us that the smallpox virus first began infecting humans approximately 10,000 years ago. This timing is not random. Rather coincides with the time when humans began living together in villages and cohabitating with newly domesticated livestock. When various mammals live in close proximity they often swap viruses. This process provides the viruses with ample opportunity to commingle their genetic material with that of their hosts, creating mutated strains of the virus. Most of the resulting mutations render the virus non-functional, but a select few can create deadly super bugs.

Archeological evidence suggests that smallpox began as a relatively mild virus before mutating into an efficient killer, with mortality rates that exceeded 30%. As early as 1,000 B.C. in India, inoculation procedures were attempted to protect people from smallpox.(1) Early techniques consisted of scraping smallpox scabs off of sufferers, grinding them up into a power, and having a healthy person sniff the power into their nose. While this sometimes resulted in deadly infections, those who survived the process were far less likely to contract smallpox in future epidemics.

The next big advance in fighting smallpox occurred in England in 1796, when Dr. Edward Jenner observed that people who had suffered from cowpox developed immunity to smallpox. He began injecting healthy people with liquid from cowpox lesions and found that this protected the recipients. Dr. Jenner was responsible for coining the term vaccination, based on the Latin word vacca meaning “from cows”. Over the next 183 years, with improvements in vaccines and steadfast global cooperation, smallpox was eradicated in 1979 and vaccinations ceased in 1980.

The smallpox vaccinations that those of us born before 1980 received also protect us against a broad range of other pox viruses, including cowpox and monkey pox. Since humans are the only host for the smallpox virus, vaccinating humans wiped out small pox.(2) Cowpox and monkey pox are far less particular about hosts than smallpox and infect a wide variety of mammals, particularly rodents. Since people born after 1980 were not vaccinated for smallpox they also lack immunity to these other pox viruses.

As you therefore might expect, infection rates of humans with cowpox and monkey pox have been steadily rising since 1980. While cowpox symptoms are generally limited to mild skin rashes, some strains of monkey pox have mortality rates approaching 10%. Furthermore, both cowpox and monkey pox are evolving in ways that have allowed them to begin infecting a wider array of mammals and to become more efficient in transferring from human to human. A 2003 outbreak of monkey pox occurred in the U.S. when rodents imported from Ghana infected a population of pet prairie dogs, which then infected their owners, who then infected their friends and relatives.

The current situation with monkey pox is quite similar to that for smallpox 10,000 years ago, a somewhat mild virus with many opportunities to spread and mutate. Of particular concern is evidence that pox viruses often undergo potentially harmful mutations when a sufferer is simultaneously infected with a retrovirus such as HIV. As luck would have it, sub-Saharan Africa, which seems to get the short end of the stick on nearly everything, has the world’s highest infection rates for both monkey pox and HIV. If no public health actions are taken, the number of people and regions affected will grow, giving monkey pox and its brother and sister viruses more and more chances to mutate into a modern-day “smallpox”. Since, unlike smallpox, monkey pox infects many different mammals, it is effectively impossible to eradicate. This suggests to me that at some point in the not-too-distant future, vaccination against pox viruses will resume. In the mean time, before you or anyone you know born after 1980 is travelling internationally, particularly if the destination is the Democratic Republic of the Congo, check the CDC and WHO websites regarding the incidence rate of monkey pox. The smallpox vaccine remains available and will provide the necessary protection.

Have a comment or question? Use the interface below or send me an email at commonscience@chapelboro.com.

 

(1) This story touches on a theme I have addressed several times in the past. Our forebears were just as smart as we; they just had less accumulated knowledge to work with.
(2) Both the United States and Russia maintain frozen samples under heavy guard. Many have suggested that these samples be destroyed. The argument to keep them centers around the possible need to use them to make vaccine in the future.

http://chapelboro.com/columns/common-science/monkey-pox-seriously/

The Power of Backpacking

Last week I went backpacking in the mountains with my son’s Boy Scout troop and took the week off from writing this column. We covered 50 miles over five rainy days with each of us carrying approximately 30 lbs of gear each in our backpacks. I suppose to some readers this sounds like a rather unappealing way to spend a week. For me, it was a nearly perfect week away from the stresses of everyday life and one in which I had some time to consider the human body as a machine which consumes energy and generates power.

Before we proceed with our discussion, I need to review some of the applicable units of measure for this discussion. First let’s consider a familiar unit of energy, the calorie. A calorie is the amount of energy needed to heat one gram of water by one degree centigrade. The energy contained in the foods that we eat can be measured in calories. Unfortunately, whenever you hear some one discuss a food calorie what they really mean is a thousand calories (a kilocalorie). Why someone decided that “kilocalorie” was too difficult to comprehend when discussing food is lost to history. So when you hear someone say that you should eat 2,000 calories a day in your diet, this is actually 2,000,000 calories. This distinction will be important in the discussion below.

Next let’s talk about units of power, which is energy expended per unit time. For example, an erg is a unit of power equal to the expenditure of one calorie per second. While knowing the definition of an erg can be quite useful if you are doing a crossword puzzle, the standard unit of measure for power is the Watt. To discuss Watts, first I need to introduce the Joule. There are 4.184 Joules in a calorie. I could explain why but this discussion of units is already probably becoming a bit tedious. A Watt is equal to one Joule per second.

OK, back to backpacking. I am 47 years old, weigh 160 lbs and am moderately active which means that my baseline expenditure of food calories every day is approximately 2,400. After doing a bit of math you can determine that my metabolism consumes an average power of 116 Watts, just a bit more than a standard light bulb. After determining my baseline power consumption, I let’s consider how much additional power I need to expend to walk, run, or backpack.

For a 160 lb person, walking 3.5 miles an hour requires 310 Watts of power and running 8 miles hour requires 1100 Watts. This large difference in power consumption corresponds to our intuitive understanding that running is much harder than walking. If I were walking for exercise I might do so for an hour which, after doing a bit of math, corresponds to an energy consumption of 267 calories. If instead I were running, I’d probably get tired after a half an hour and stop, by which time I would have burned 473 calories. Adding up the totals and rounding off a bit, on a day when I walk for an hour my body uses 2700 calories, 2400 as background metabolism and 300 more from walking. On a day when I ran for half an hour my total calorie consumption would be approximately 2900 calories.

As I was lugging my pack through the mountains, it felt like I had to generate significant power to keep moving and, therefore, would be expending quite a few calories. Due to this extra load and uneven footing on the trail, my walking speed was approximately 2 miles an hour. A 190 lb person – 160 lbs of me plus 30 lbs of backpack – walking at 2 miles and hour expends 210 Watts of power. On a typical day of backpacking I walk for six hours which corresponds to the consumption of 1084 calories. Of course the challenging part of backpacking is not the linear distance but the vertical climb. On a typical day I would average a cumulative elevation gain of 2,500 ft. Lifting myself and my pack up those hills requires another 506 calories.

Adding this altogether, on a backpacking day my body will expend approximately 4,000 food calories of energy. This calculation helps to explain an aspect of backpacking which appeals to those of us who have reached our 4th decade. While we are on the trail we can eat like teenagers again, which, at least for a little while, is kind of awesome.

Have a comment, question, or backpacking story? Use the interface below or send me an email to commonscience@chapelboro.com.

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Cougars in Chapel Hill in 2035?

You may recall some excitement in Chapel Hill in December of 2008 when there was a reported cougar sighting near the UNC golf course.  Like many cougar sightings in North Carolina, this one was not confirmed by state wildlife officials.  But cougars are on the move eastward from the Rockies and are likely to return to the area some day.  The question is when?  Common Science is here to try to answer that question.

The discussion of cougars gets complicated by the many names given to the species including puma, mountain lion, and catamount.  They are all the same.  Prior to European colonization, cougars ranged through most of the United States and Canada, feeding primarily on deer, elk, and moose.  Cougars, males in particular, are solitary, territorial, and nocturnal.  Their maximum population densities average only four cougars for every 40 square miles, or 0.1 per square mile, a number to which we will refer back later.  Therefore, even when cougars are at their normal population densities, sightings are usually rare.

When U.S. and Canadian settlers pushed westward, they considered the cougar to be a menace and a nuisance and killed them indiscriminately.  Additionally, even though the losses of livestock were statistically low, farmers and ranchers successfully lobbied their respective state governments to pay bounties for dead cougars.  By the 1950s, with the exception of a an isolated population in the Florida Everglades, all cougars east of the Mississippi river had been eliminated and the population between the Mississippi and the Rocky Mountains was nearly wiped out as well.  By the 1960s and 1970s, most states repealed the bounties and imposed regulations against indiscriminate killing of cougars, allowing the populations to begin a slow rebound.  At present, it is estimated that the cougar population in the U.S. is somewhere between 30,000 and 50,000.

The vanguard of a cougar migration consists of juvenile males who need to find available territories to avoid conflicts with older males.  Occasionally a lone male will travel hundreds of miles out of range, which accounts for the infrequent but intriguing reports of cougars along the eastern seaboard, including a recent confirmed sighting in Connecticut.  However, the re-establishment of a stable population in a new area must await the arrival of both genders.  The eastward migration of the cougar is being tracked via confirmed sightings in midwest states, including Oklahoma, Missouri, Illinois, and Arkansas.  Cougar sightings in these states grew from just two in 1990 to 34 in 2008, suggesting a noteworthy increase in population density during this time interval.

This brings me to the reason I find the phenomena of animal migrations to be interesting, and which will usher in the section of this column which is almost certain to differentiate it from any other column you encounter covering the return of the cougar to the eastern United States.   The movement of animal populations can be modeled with diffusion equations, a tool often used by engineers like me.    Diffusion equations are used to determine the rate of movement of materials from an area of high concentration to one of low concentration.  If you’d like to run your own diffusion experiment, put a drop of food dye into a glass of water and watch.  Initially, the area where the drop landed will have high concentration of dye.  With time, molecules of the dye will migrate away from the area of high concentration to zones of water in the glass which have low or no concentration of dye.

The dynamics of this simple kitchen experiment have a lengthy and elegant mathematical explanation which culminates in Fick’s Law of Diffusion. I’m tempted to include a thorough explanation of the underlying mathematics of Fick’s Law, but I’m not so sure you’d be tempted to read it.  What I would like you to consider however, is that the migration of the cougar and the diffusion of the food dye are quite similar.  In the case of the cougars, the area near the Rocky Mountains which contains 0.1 cougars per square mile is like the drop of food dye, and the area bereft of cougars east of the Rockies is like the rest of the water in the glass.  Therefore, we can use Fick’s Law to try to predict when the cougar will return to the southern part of heaven.

If you look at the map below, the western most dashed line runs approximately along the north-south axis of the Rocky Mountains.   About 500 miles to the east, shown by the vertical dashed line called D1  (distance 1), the cougar population density was such that there were just 2 sightings in 1990.  We don’t know the exact population density of cougars along D1 in 1990, but we know it was low.  In my calculations, I assigned it a value of 0.002 cougars per square mile.  I can’t know if this is correct, but as long as I am consistent with the assumption that a population density of 0.002 cougars per square mile will result in 2 sightings per year, the subsequent predictions will still work.  (I need you to trust me on that one.)  The line D2 on the map indicates the location of Chapel Hill, which is approximately 1400 miles east of the Rockies.

Cougar Map

Now that I have the population density of cougars for two locations in 1990, the Rockies and the line D1, I can model the population density of cougars as a function of distance using Fick’s Law.  This is shown by the blue line on the graph below.  By 2008, the number of sightings in the D1 area rose to 34 per year.  Since sightings increased by a factor of 17, from 2 to 34, it is reasonable to assume that the population density increased by a factor of 17 as well.  Using this assumption, the population density as a function of distance for 2008 is shown with the purple line.  The curve for 2008 suggests that by this time cougars should have begun recapturing western Tennessee as part of their range.  News reports conflict as usual, but there is strong anecdotal evidence that they did return to the Volunteer State around that time.

Cougar GraphUsing this model, I can calculate how long it should take for the population density in Chapel Hill to reach 0.002 cougars per square mile, the level at which we could expected to begin to see confirmed sightings from a resident population consisting of both males and females.  This is shown on the graph with the green line, suggesting that in addition to jaguars, tigers, and wildcats (our high school mascots in case you missed the reference), Chapel Hill will have cougars in 2035.  If we ever need to build a fourth High School, then the choice for a mascot is obvious.

Have a comment or question?  Use the interface below or send me an email to commonscience@chapelboro.com.

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By Way Of Introduction

Hey y’all.

If you’re reading this, you likely know me as WCHL’s (former) news director and (current) evening news anchor; some of you may also know that I perform at the DSI Comedy Theater in Carrboro. And you advanced scholars will know that it was comedy that brought me to WCHL in the first place—back in 2010 I was head writer for “DSI Witness News,” a comedy spot that riffed on local people and events, and the folks at WCHL liked it so much they asked me to do real news too. True story.

Anyway. I served as WCHL’s news director for the last year and a half, but earlier this month I handed the reins to Christopher Hosken—(insert long sigh of relief here)—leaving me with some actual free time. So as of today, I’m adding “Local Buzz columnist” to my resume. Consider this my intro chapter.

So what’s this column going to be about? I’m not a science wizard like Jeff Danner; I don’t know North Carolina like DG Martin; and while I may look like a geek, I can’t hold a candle to Alicia Korenman. (And sadly, I’m not a kid anymore.) What I can offer, though, is some interesting political insight, a dash of snarky skepticism, and a fair bit of decent comic timing—so we’ll go with that, I think. For starters.

Also, I have a Ph.D. in political theory. That might help.

I want to leave the theme as open-ended as possible, for now, but this column is going to be about insights—different perspectives, thought-provoking ideas, bits of information you may not know, obvious facts we conveniently forget. I’m not really interested in taking specific positions on this issue or that: what I want to do instead is examine the debate around the issue and point out the things we’re missing, basic points that might make our political discourse a bit more informed and less—you know, eye-rollingly silly.

Or sometimes I might talk about a movie I’ve just seen. Whatever. This is my page, I do what I want.

Anyway, that’s my introduction. Email me (akeck@wchl.com) and let me know what you’d like me to write about.

http://chapelboro.com/columns/aaron-keck/by-way-of-introduction/

It’s "Political" Science!

Elections are big deals in political science and there’s nothing that political scientist love more than using elections to test their theories.  Thinking about this primary season that we are now in however, reminds me more of natural science.  I’ll leave the scientific explanations to my colleague Jeff Danner, but I can’t help but see Newton’s “action – reaction” thing at work here.  The mind is a little fuzzy all these years later about all of the details, and I guess I could do the scholarly thing and look it up on that definitive source Wikipedia, but let’s just keep it simple: this primary season has races that really fit the “action – reaction” law.  Moreover, there are some other science things at work in this election too.

On February 29th (it was leap day, and I’ll not even attempt to explain the scientific reason why we have it!), filing for the May 8th party primaries closed, so we knew who was running.  Earlier, when the Board of Elections opened fillings on February 13th, there was a lot of excitement and even anxiety because of the political shocker of the year: on January 26th, Governor Beverly Perdue announced that she would not run for a second term.  And goodness, were there reactions!  Naturally, the common question was, “Who would file?”  Since another scientific truth is that nature abhors a vacuum, we could put our money on the fact that there would be people who would rush in.

So here’s how it went.  On the first day of filing, Bill Faison, to the surprise of only a few, signed up to run for governor.  By doing that, his House District 50 seat, which includes part of Chapel Hill and moves north through Orange County, was now an open seat.  Since we already know about that vacuum thing, Valarie Foushee filed to run to fill that seat the very same day.  As Valarie currently holds a seat on the Orange County Board of Commissioners, her decision not to run again (Valarie was first elected in 2004) created an open seat in Commissioner District 1.

Two people will be elected to represent District 1, and incumbent Pam Hemminger filed on February 13th to run for her second term.  The next day, Chapel Hill Town Council member Penny Rich also filed to run, and on February 20th, former Carrboro Board of Alderman member Mark Dorosin entered the race too.  Now here’s another scientific fact: three people competing for two seats means one can’t have the seat, so this will be what politicians call a real horse race.  Of course, we have to wonder if the usual incumbent’s advantage will work in this race, or could the sitting commissioner lose her seat.

If Ms. Rich wins, she would have to resign from the Chapel Hill Town Council, since we don’t allow people to hold two elected offices simultaneously (not that anyone is crazy enough to want to do it, are they?).  Her resignation would cause the other eight members to choose a new ninth member to serve for a year, and we all know from prior experience how much fun that “filling the vacancy” scientific process is.  If she doesn’t win, she would continue to serve the final year of her Council term.

The other reaction to note is that this many seats, whether held by incumbents or open, tend to draw other candidates.  Hence, you can go to the State Board of election website and see all of the people running for the various federal and state offices.  You can also go to the Orange County Board of Elections website to see who’s running in our State Senate, State House, County Commissioner, and Orange County Board of Education races.  What’s interesting this year is that, in some of our races, winning the Democratic primary will not be tantamount to being elected, as there are seats where the winning Democrat will face the winning Republican in the general election.  In contrast, the four incumbent District Court judges on our ballot are all running for the nonpartisan bench seats without opposition.

As the campaign season heats up and we experience the familiar process of campaign forums, meet and greets, letters to the editor, mailers, and campaign signs, we need to pay attention.  The national and statewide campaigns will spend tons on television and radio ads, but our local campaigns tend to be more direct.  This primary will also have increased attention and maybe participation because of Amendment 1 being on the ballot.  You can read the official explanation of the it by visiting this page.  People on both sides of the issue will spend small fortunes to get people out to vote for or against the constitutional amendment, and voter participation is a good thing.

It’s later than you think, so get familiar with the issues and with the candidates and their positions because on April 19th “One-Stop Voting” begins, and it ends on Saturday May 5th at 1 p.m.  Election Day is Tuesday May 8th.  Polls will open 6:30 a.m. and won’t close until 7:30 p.m. 

After the election, someone will claim they didn’t vote because they didn’t know anything about the candidates, or they were simply unaware of the election, or their one vote really didn’t matter, or tell you that it’s just a primary.  And folks, sad though it is, it’s as true as night follows day and as sure as the sun rising in the east.  And those are both scientific facts!

http://chapelboro.com/columns/fred-said/its-political-science/

It's Not Obdurate Stupidity (Response to "Common Science")

This T.W.O. Cents Column is in response to“It’s a Theory That’s Out There” - from Common Science, by Jeff Danner.

You ask what people, and especially politicians, mean when they say “no” to science, and particularly evolution. I believe it is because people compartmentalize their understanding.

Science is perceived to be the first step toward engineering, toward control. That’s great for cell phones and rockets. Evolution is about sex and death. The perception of science’s connection to engineering means that evolution is the first step to controlling who has sex and who dies, and that it’s not going to be the way our parents did it. This perception is not wholly without foundation: eugenics was a “scientific” idea – and now we’re trying to figure out reparations. Birth control and abortion have shaped behavior in a way that horrifies traditional communities. You’re probably not familiar with the details of nuclear weapon detonation. For similar reasons, many think that teaching human evolution is a questionable idea.

Human evolution is on the wrong time scale for the 24 hour news cycle.

A six thousand year time scale fits better with most people’s imagination than a 13.7 billion year history. It is disturbing to many that human beings (the ones that matter, anyway) might be importantly different from the ones described in sacred texts.

Philosophy and religion are not studied in our schools, and therefore when most people seek capital T Truth, they look to sacred traditions that have often become quite parochial, and many of those traditions have no trouble believing creation to have been so polluted by Satan that false evidence (e.g., fossils) permeates the world the way evil desires permeate the soul.

If you, as I, think that capital T Truth includes evolution, then we must first talk about Truth, and then we have to connect evolution to what people value – even if they think they value something more than Truth, which may sometimes be safety, sometimes compassion, and in a few sad cases, simple comfort or fleeting power.

It might be quite a departure for a “science” column.

http://chapelboro.com/columns/the-commentators/its-not-obdurate-stupidity-response-to-common-science/