The science of climate change has been explained many times to many people. Some people understand it, and some people don’t. Many people that don’t fully understand the process that unfolds with too much carbon dioxide in the atmosphere understand that the scientists who study climate change know the process step-by-step. The scientists study it, tell us what will happen if the problem isn’t cared for, and suggest possible solutions.
But there are other people who do not fully understand the chain of events that happens when too much carbon dioxide is in the atmosphere who think that because they don’t understand it, it doesn’t exist and that the climate scientists don’t know what they’re talking about.
I would like to detail another complicated reaction. One that happens when too much carbon dioxide builds up, not in the atmosphere, but in the human body. There are scientists that study this, tell us what will happen if the problem isn’t cared for, and suggest possible solutions.
Every person that denies the events that occur as a result of too much CO2 in the external environment needs to think about what they would do if too much CO2 built up in their own internal environment.
In living organisms, including our own human bodies, there is a system called homeostasis. This system exists to make sure each element in your body stays balanced with all the other elements. It ensures that your body, as it exists, remains in a constant state that is compatible with life. When one element is thrown out of whack, we have compensatory mechanisms that gear up to balance this out. Our bodies are amazing machines when it comes to homeostasis.
But what happens when our homeostatic mechanisms are overwhelmed?
Let’s look at carbon dioxide, for example. We all know that too much of this gas is not good for our bodies. And most of us have the scientific knowledge to understand that we breath in oxygen and breath out carbon dioxide. We breath it out because it is not a useful gas for us.
Normally, we can balance the intake of oxygen and output of carbon dioxide even if we are faced with a little bit of extra carbon dioxide in our bodies. This happens by way of our bodies’ remarkable mechanisms of homeostasis.
But before we get into our bodies’ homeostatic mechanisms when it comes to carbon dioxide, there is one fact that needs to be understood: CARBON DIOXIDE IS AN ACID. So too much carbon dioxide in your body acidifies your internal environment. This is not good. And our bodies do what they can to expel this potential poison.
The first thing that our bodies do to get rid of extra carbon dioxide is to speed up respiration. That is, we start breathing faster to blow off the extra CO2. Unfortunately, this is where some people run into trouble.
What happens if we are unable to expel carbon dioxide through respiration (breathing)?
First of all, you may think this is an uncommon problem. After all, everyone you see around you is breathing. But there are certain subsets of people who are not always efficient at the oxygen/ carbon dioxide gas exchange. Like people with asthma, Chronic Obstructive Pulmonary Disease (COPD), chronic bronchitis, or sleep apnea.
Many people suffering from these conditions have difficulty exhaling due to swollen and constricted airways as well as excessive mucus production. One can hear this difficulty exhaling as the sound of an expiratory wheeze when listening through a stethoscope.
Those in the health profession may observe other subtle symptoms in long-time sufferers. They sometimes refer to these types of patients as blue bloaters. Blue, because their lips may appear blue from cyanosis (bluish color of the mucus membranes and extremities due to lack of oxygen in the blood). Bloaters, because these patients often appear bloated or stocky because they are holding onto extra, unusable gases.
If you took a blood sample from an artery of one of these chronic patients, you would see that the partial pressure of carbon dioxide is way higher than it should be. That is to say, there is an increase in amount of CO2 in the blood that is being pumped AWAY from the heart to be used by the rest of the body. Additionally, the partial pressure of oxygen in the blood decreases, because the carbon dioxide is saturating the blood. The body is not getting the fuel it needs to function. Furthermore, the body is using the little oxygen it has to power itself and creating more CO2 as a byproduct of metabolism.
This leads to something called respiratory acidosis (carbon dioxide combines with water to form carbonic acid, H2CO3) and can ultimately be measured as a drop in the pH of the blood. The body tries to fix this in two ways:
It tries to balance the extra acid by producing more base (in the form of bicarbonate).
It tries to excrete the extra acid via the kidneys (meaning that your body tries to pee out the carbonic acid and hold on to the bicarbonate).
After the body maxes out the effectiveness of these two methods of maintaining acid/base balance, it may move on to another compensatory mechanism: increased erythropoiesis. That is to say, it will increase the number of circulating red blood cells. These extra red blood cells, the body thinks, will help more oxygen circulate through the blood. It makes sense because oxygen attaches itself to the hemoglobin in the red blood cells as if it was riding on a trolley through San Francisco. It travels to where it needs to go, then hops off to power a muscle somewhere.
Unfortunately, too many red blood cells can be produced. When this happens, it is called polycythemia. Simply stated, too many red blood cells can clog up your blood vessels, leading to impaired circulation and even stroke.
Another thing your body does when faced with decreased oxygen supply is to cut off circulation to parts of your lungs. This increases the blood pressure in your lungs, which increases the amount of effort the right side of your heart needs to exert to push the blood through your lungs, which can then lead to right-sided heart failure.
On top of all that, increased levels of CO2 in your blood causes headaches, confusion, sleepiness, and increased intracranial pressure (in and around your brain).
Scientists who have studied this know what’s going on and know how to make it better. They’re called physicians. I’m sure that if you had any of these symptoms, you would trust the experts with your care.
There are other scientists who study what happens to the earth on a larger scale if too much carbon dioxide builds up in our external environment. They’re called climate scientists.
It it always important to remember that not everyone celebrates the same holidays in the same ways. There is always someone out there that does something different. And different is ok. Teaching our children this as we celebrate our holidays is an integral way to move us toward a more tolerant and accepting society. This post is how our family celebrated Easter this year, starting with learning about the history of this holiday.
Before the Christian religion co-opted Easter as its own holiday, the Anglo-Saxons celebrated the goddess of fertility and spring, Eostre. The symbolism surrounding modern-day Easter can easily be explained by exploring how the Anglo-Saxons celebrated: Eostre’s earthly symbol was the rabbit and, quite obviously, eggs are symbols of fertility.
As I reflect on this, I cannot help but notice the switch from celebrating a woman for her life-giving power to celebrating something quite the opposite. In any event, our family set out to commemorate Eostre, do some science, and enjoy a lovely spring day.
First, we started a little science experiment to make an egg that bounces. The experiment is still in progress. But we did the first step:
Place egg in bowl and cover with vinegar.
Wait 3 days for the completion of a chemical reaction between the calcium carbonate of the eggshell and the acetic acid in the vinegar. (You can see some bubbles of carbon dioxide forming on the egg below.)
We’ll see if it works.
Next, we dyed eggs experimenting with natural materials. The materials we chose were beets, purple sweet potatoes, spinach, and turmeric.
To make the dye, we placed a generous amount of each into their own pot of boiling water along with 2 tablespoons of vinegar and simmered for 30 minutes.
After straining the natural materials from the dye mixtures, we let them cool for a bit before placing the already hard-boiled eggs in them to soak up the dye. Natural dyes are not as intense as the dyes from the store, but they are beautiful.
And you get mashed purple sweet potatoes!
We finished up our family secular Easter for the Restivus with mud puddles and shooting hoops. Fun!
UPDATE: After 4 days, we removed our eggs from the vinegar and, sure enough, they bounced!
My son shot this video as he instructed his sister to bounce it higher.
She didn’t, so he bounced his higher. This is what happened:
1. Divest. Move your money from a for-profit bank to a not-for-profit credit union. Credit unions offer the same benefits as banks, but you become an owner. The purpose of a for-profit bank is just that – to make money. Banks invest in things like the Dakota Access Pipeline and expect a return on their investment. Putting your money in those banks helps them invest in projects that you may not support. Credit unions are a much better option.
2. Find your park. Did you know that park rangers for the National Park Service were early leaders in the resistance? They were the first group of federal employees the Trump administration gagged because they sent out that famous (now deleted) tweet decrying Trump’s claim that the inauguration crowd was YUUUUGE.
Also, on January 24, 2017 Jason Chaffetz (R-Utah), chair of the House Oversight Committee that refused to investigate Trump, introduced House Bill 621, to sell off 3.3 million acres of federal park lands. Luckily, because he was met with such resistance he withdrew the bill.
3. Subscribe to a reputable news outlet. Show your support for investigative journalism (and the 1st Amendment). With the Republican majority in Congress, freedom of the press seems to be the only check or balance we have on executive power these days. You can even give a gift subscription to someone who may need to be a little more informed. As the Washington Post‘s new slogan says: Democracy Dies in Darkness.
4. Support STEM/STEAM education. STEM/STEAM teaches critical thinking, creativity, ingenuity, and problem-solving. Students who are educated Science, Technology, Engineering, Art, and Math are, literally, going to save the world.
5. Take care of you. Seriously, fighting fascism is exhausting. Especially when you feel like just one little, tiny person fighting a giant cabal. Take a day or two every now and again to recenter yourself. Then get back in the fight again!
Do you know of any more easy ways to change the world for the better? Please share them in the comments below.
In this age, where the Republican administration is relying on “alternative facts,” gagging federal employees, and barring reputable news sources from White House briefings, effective communication of factual, evidence-based information is now more important than ever.
In order to effectively communicate, two things need to happen:
1) a signal must be transmitted, and
2) a signal must be received.
I have found, in my own political communication with those who do not share my viewpoint, that although I am transmitting what I consider to be thought-out, evidence-based ideas, those ideas fall on deaf ears. That is, although I am transmitting a clear signal, my signal is not being received. Therefore, I am not communicating effectively.
My failed communication is partly my fault, and partly the other person’s fault. Let me start by telling you why the other person is at fault, and then I will share some ideas that I’ve been pondering about how to communicate more effectively.
First, when talking about how the other person is at fault, we must consider something called confirmation bias. Confirmation bias is the search for and interpretation of information that conforms to one’s preconceived notion of ‘truth.’ That is to say, the receiver only receives information that confirms his ‘truth’ and disregards information that does not. (Think of your favorite Fox News viewer here.)
Further, people who rely on an incompetent (or intentionally lying) source usually surround themselves with others who rely on that same source. They all become more emboldened to believe their ‘truth’ together because they are now not alone in their belief.
Further still, there is even some evidence that people get a rush of dopamine (the addiction chemical) when they come across information–true or not–that confirms their point of view.
Unconscious incompetence and Illusion of explanatory depth
Second, we have unconscious incompetence. This describes people who are unaware that they are NOT knowledgeable on a certain topic. (A simple example is someone who points to a guitar and vehemently insists that it is a giraffe – even posting diatribes on Facebook about it.)
Researchers call this the illusion of explanatory depth. In some domains this illusion is just fine. We don’t need to know the details of toilet ‘flush-age’ or exactly how a cylinder lock works in order to properly use these devices.
However, when it comes to politics or climate change or reproductive rights or LGBTQ rights or vaccinations or the 2nd amendment or an immigrant ban (the list goes on), this illusion of explanatory depth becomes dangerous. Citizens are voicing their opinions, voting, and affecting policy (and posting diatribes on Facebook) on issues which they know little about. But these issues affect the health and safety of others greatly.
So what can we do to communicate more effectively when faced with others’ confirmation bias, unconscious incompetence, and illusion of explanatory depth?
The onus is on us
Like it or not, we who are communicating rational, evidence-based information have to bear the burden of changing how we communicate in order to make our message heard. In other words, we should consider marketing the message. We can do this in four ways:
Appeal to emotion. Understand that merely providing statistics does nothing to open the mind or pierce the intellectual barrier of someone with confirmation bias, unconscious incompetence, or the illusion of explanatory depth. Simply put, citing the statistic that a person’s chance of dying in an airplane crash is one in 11 million, will do nothing to quell the fears of a terrified air passenger clutching his armrests on takeoff. We are emotional beings. (As a side note, appealing to emotion is something that science communicators definitely need to use more of.)
Understand that conservatives and liberals process the world in very different ways. A recent study by John Hibbing at the University of Nebraska (summarized here) showed that conservatives have a stronger negativity bias than liberals do. That is, they focus more on negative stimuli and respond accordingly, suggesting they have more of a “threat-oriented biology.” Furthermore, a 2003 study provided evidence that conservatives also have a “need for certainty” and an “intolerance of ambiguity.” This explains their stance on many issues including gun ownership, immigrant bans, LGBTQ discrimination, etc.
Invoke nostalgia, and the return to a “better” time. Conservatives love the thought of “restoring” America to its former glory. Even if the aim is to restore a glory that never existed. (And we all know that the nostalgia is for a time in which many marginalized people did not have the rights they now have.) Researchers at the University of Cologne in Germany decided to test this restoration bias when it comes to environmentalism. Their recent study found that conservative thinkers donated more to a hypothetical environmental charity that aimed to restore the planet to a previously healthy state, rather than one that favored preventing a future disaster.
Exploit the illusion of explanatory depth. If someone is making an untrue claim, ask for a deeper explanation of the topic. As in the Yale study above, that person may expose their own unconscious incompetence to themselves (thereby making it conscious), and will less fervently defend their view. Hopefully, just exposing their lack of important knowledge will lead them to seek out factual information to fill in that gap. (I know, it’s a long shot.) N.B.: This approach may backfire if engaging in debate on social media, as your debate partner may realize his lack of explanatory depth and provide you with a link to an article from their favorite right-wing blog.
Facts are vitally important to the survival of our democracy. It’s time to start calling out the people who are peddling in the currency of unverifiable information. The old strategy of ‘ignore them and they’ll go away’ isn’t working anymore. Engaging in civil debate with those who are spouting false statements that are not supported by any scientific evidence is a now a civic responsibility. Arm yourself with evidence-based information and the strategies outlined above.
Last Friday, President Trump’s administration put a gag order on the Department of the Interior, which includes the National Park Service, limiting their ability to communicate to the public through social media. This was in response to an NPS retweet comparing crowd size at Obama’s 2009 inaugural to Trump’s inaugural. See the original tweet below (the NPS retweet has been deleted and a public apology was issued):
Last night, someone at @BadlandsNPS went rogue and started tweeting out climate change facts. These tweets were subsequently deleted. Below are screenshots of the tweets that I retweeted yesterday afternoon. My retweets have disappeared as well.
This led to the formation of an unofficial NPS twitter handle @AltNatParkServ (UPTDATE: changed to @NotAltWorld), along with @BadHombreNPS and @BadIandsNPS – the L had been replaced with a capital I to create a new twitter handle. (Also, it seems @BadIandsNPS has been changed to @BadlandsNPSfans – see screen shots from last night below.)
Here are some of the tweets:
Recent research suggests that polar bears don't actually like the cold, so they're fine with climate change. pic.twitter.com/WLxDOnTZTQ
Climate change science is bad for Donald Trump. He wants to make a profit for himself and his cronies, and those pesky science facts will keep him from doing so. He’s working diligently to try to wipe climate change facts out of reach of the public, recently barring the Environmental Protection Agency from mentioning climate change on its website.
I recommend you check out the aforementioned twitter feeds before they’re taken down as well. And teach your kids about climate science!
Have there been cutbacks? Sure. But take it from us: the Trump administration is still committed to rigorous scientific research. pic.twitter.com/hQKI5ifumA
Explore hypothetical situation concerning unethical medical experimentation
Briefly discuss real-life Nazi medical experimentation
Discuss perspectives on what to do with unethically obtained data
Above: Photo of Karl Brandt, personal physician to Hitler, active in SS, Commissioner for Health and Sanitation. After WWII, he was tried at Nuremberg and found guilty of war crimes, crimes against humanity, and membership of a criminal organization. He was executed by hanging in 1948.
The Nuremberg Code
The Nuremberg Code came about after the 1947 Nuremberg “Doctors’ Trial” in which several Nazi physicians who performed cruel experiments on unwitting human subjects were tried. The Nuremberg Code comprises 10 directives for human experimentation and is still relevant today.
Nuremberg Code, briefly stated:
Obtain voluntary consent of all human subjects
Perform experiments that will benefit society and are not unnecessary
Expect that the results will give good reason for the experiment
Avoid suffering by or injury to the subjects
Do not perform experiment if there is any belief that death or disabling injury will occur
Make sure the risk taken by the subject does not surpass the importance of the results of the experiment
Protect the subjects from injury or death
Ensure that only “scientifically qualified persons” are performing the experiments
Cease the experiment if the subject feels physically or mentally pushed to the limit
Expect that lead scientist will call the experiment to an end if he or she believes there is a danger to the subject
These directives for human experimentation seem simple and reasonable. However, misguided researchers have, in the past, and may, in the future, stray from these guidelines. The question, then, is what do we do with data gleaned from unethical experimentation? Especially if the data are valuable to the health and well-being of our patients.
This is a very difficult question to tackle. In order to tackle this question, I will employ a technique that has been employed by teachers since Socrates. We will explore a hypothetical situation that deals with the topic at hand.
Although our particular hypothetical situation is from popular culture, it is not meant to trivialize the issue. Rather, this hypothetical is meant as a vehicle for serious thought and exploration. Our hypothetical situation comes from the television show Star Trek: Voyager, episode 8 from season 5 entitled “Nothing Human.”
Here is a brief summary of the episode: The ship’s chief engineer Lt. B’Elanna Torres finds herself in a situation in which an alien being has attached itself to her, piercing her vital organs, in an attempt to keep itself alive while sapping the life from her. Lt. Torres will die if the alien is not removed properly. Unfortunately, the ship’s holographic doctor has no idea how to remove the alien and save B’Elanna’s life. The doctor says he needs to consult an expert in alien biology, an exobiologist. A plan is construed to create a hologram of Dr. Crell Moset, a Cardassian physician who is a leader in the field of exobiology.
Dr. Crell Moset also cured the fictional, but deadly, fostossa virus. The fact that Dr. Crell Moset is of a race called the Cardassians is of some consequence, especially to a crew member whose planet was occupied by the Cardassians during ‘the war.’ When that crew member expresses concern, the ship’s doctor states that he doesn’t care if Moset was the “nastiest man who ever lived,” as long as he can help save Torres’ life.
A conflict arises when Ensign Tabor, the Bajoran officer whose planet was occupied by the Cardassians, recognizes Dr. Moset. He is horrified, explaining:
“I can still remember the sounds his instruments made; the screams of his patients; the smell of chemicals and dead flesh. He operated on my grandfather, exposed his internal organs to nadion radiation. It took six days for him to die.”
The following conversation between Ensign Tabor and the Doctor reveals the more about Crell Moset’s experimentation on unwitting subjects:
Ensign Tabor: He blinded people so he could study how they adapted; exposed them to polytrinic acid just to see how long it would take for their skin to heal!
Doctor: Ensign, the man you’re accusing cured the fostossa virus. He stopped an epidemic that killed thousands of Bajorans!
Ensign: By infecting hundreds of people. So that he could experiment with different treatments; old, helpless people, like my grandfather, because he considered their lives worthless!
Doctor: How do you know this?
Ensign: Everybody knew.
So, although yielding useful results, Dr. Moset employed unethical methods in his research.
The dilemma we are faced with is now two-fold:
Is it moral to use Dr. Moset’s knowledge, which was gained through the blood of innocents, to help save a crew member’s life?
Would using the knowledge set a dangerous precedent for the future, thereby condoning such cruel research methods?
Ensign Tabor, after learning that Dr. Moset enjoys a position as the chair of exobiology at a university, offers this as a solution to the aforementioned dilemma:
“We may not be able to do anything about the real Moset, Commander, but the program should be destroyed. Every trace of that man’s research should be deleted from the database.”
The commanding officers also struggle with the dilemma:
Lt. Tuvok: If the Doctor uses knowledge that Moset gained through his experiments, we would be validating his methods, inviting further unethical research.
First Officer Chakotay: We’d be setting a terrible precedent.
Lt. Paris: We’re in the middle of the Delta Quadrant, who would know?
Lt. Tuvok:We would know.
Lt. Paris: Fine. Let’s just deactivate the evil hologram and let B’Elanna die. At least we’d have our morals intact.
It is interesting to note that Tuvok, who is a Vulcan (an exemplar of logical thinking) posits that validating the methods of an unethical researcher may invite further unethical research.
For the captain of the ship, there is no question that Lt. Torres’ life should be saved, so she orders it done. But, a question still persists: what should be done with the file containing the information from Moset’s research after the current situation is resolved? Should it be deleted? Or, should it be kept for future medical emergencies?
Nazi Experimentation on Human Subjects in Concentration Camps
Unfortunately, such a situation is not merely a hypothetical. The Nazis performed many gruesome and inhumane medical experiments on inhabitants of concentration camps. Before we find out how the characters in our hypothetical situation resolve this ethical dilemma, I would like to briefly explore some of types of Nazi experiments that took place on human subjects.
Theses experiments included:
Freezing experiments in which inmates were submerged in tanks of ice water and left to shiver to death to see how long a human could survive in freezing waters.
High altitude experiments in which subjects were put in decompression chambers to simulate high altitudes, then their living brains were dissected to see the air bubbles that would form in subarachnoid vessels.
Sulfanilamide experiments in which wounds were inflicted on prisoners and infected with bacteria, then treated with the new drug (sulfanilamide) to see how well it would work to fight the infections.
Sterilization experiments and artificial insemination experiments.
Tuberculosis experiments in which axillary lymph glands were removed from Jewish children to see if there were natural immunities to the disease from which a vaccine could be developed.
Surprisingly, or perhaps not so for some, many modern scientific journal articles cite the data produced in the types of experiments listed above. One of the authors of the book Hypothermia Frostbite and other Cold Injuries uses Nazi data in his research. Also, the survival suit, which you may have seen on the TV show “The Deadliest Catch,” the suit that allows people to survive in freezing cold waters, came about as a result of using Nazi data.
Let us take into consideration the following quote from Kristine Moe from the essay “Should the Nazi Research Data be Cited?”: “Nor, however, should we let the inhumanity of such experiments blind us to the possibility that some ‘good’ may be salvaged from the ashes.”
We are left puzzling about what to do with this data gleaned with unethical medical experimentation. If we use it, is it setting a terrible precedent for the future? If we don’t use it, are we just letting bad things happen without salvaging any good from it?
We do have this question: What should the medical community do with data from research that was performed in a way that did not respect the rights of human beings as was the case with Nazi human experimentation?
The Doctor’s Dilemma
The holographic doctor in our hypothetical situation also struggles with this dilemma:
Doctor (to holographic Moset): Your program, despite all it’s brilliance, is based on his work. He infected patients, exposed them to polytrinic acid, mutilated their living bodies. And now we’re reaping the benefits of those experiments. Medically, ethically, it’s wrong.
Moset: What do you suggest we do about it?
Doctor: I’m not sure. We may have to delete your program.
Moset’s holographic image then argues that such is the price one pays to further medical science. He then makes the point that much of the medical data banks would have to be erased due to questionable ethics in research methods. And argues further the ever-popular idea that ethics are relative.
The doctor responds that sometimes the price is too high. Just because Moset cured a deadly virus that would have killed many more if gone unchecked, that does not justify inhumanely using people in his experiments. Interestingly, the decision of whether or not keep the file containing the holographic image of Dr. Crel Moset (and all of the data that goes along with that) is left up to the ship’s Doctor:
Crell Moset: You can erase my program Doctor, but you can never change the fact that you’ve already used some of my research. Where was your conscience when B’Elanna was dying on that table? Ethics, morality, conscience. Funny how they all go out the airlock when we need something. Are you and I really so different?
Doctor: Computer, delete medical consultant program and all related files.
The Doctor makes the decision to wipe the files of Moset out of the computer’s memory banks.
In real life, there are opposing views of what to do with research involving unethical experimentation. Brigadier General Telford Taylor, chief counsel for the prosecution during the Nuremberg “Doctors’ Trial,” felt the wisdom gleaned from the Nazi experiments should not be utilized. In his opening statement, he asserted, “These experiments revealed nothing which civilized medicine can use.”
On the other hand, John S Hayward, from the University of Victoria in British Columbia, uses Nazi data in his research on hypothermia. He states, “I don’t want to have to use this data, but there is no other and will be no other in an ethical world.”
Still others feel that the data from inhumane experiments should only be used “in the most exceptional circumstances” and solely “in the absence of ethically derived data.”
In order to decide what the medical community should do with data from unethical human medical experimentation, we need to ask ourselves:
Can some ‘good’ be salvaged from the ashes, as Kristen Moe asserts in the above quote?
How does one cite the data if one is to use it?
Does one ignore where the data came from?
Or, like the Doctor from Voyager suggests when he responds to Moset’s request to publish a paper together: “A footnote, perhaps. For further details, see Cardassian death camps.”
We do not, as a community, have an answer to the question of what to do with data from unethical medical experiments. We do, however, have a moral imperative: We must make sure ethical guidelines like the Nuremberg Code are followed when experimenting with humans; we must make sure that we never again let anything like what happened during the Nazi human experiments happen again; and we must always consider the precedent that we are setting for the future.
Garfield, E. Current Contents #28, p.3-13, July 15, 1985.
Moe, K. “Should the Nazi Research Data be Cited?” Hasting Center Report, December, 1984 pp. 5-7.
Garfield, E. “Citing Nazi ‘Research’: To Do So Without Condemnation is Not Defensible.” Essays of an Information Scientist: Science Reviews, Journalism Inventiveness and Other Essays, Vol 14, p. 328-9, 1991.
If you ask me, it’s never too early to learn something.
My little girl asked me why I have brown eyes while she has blue eyes. I told her it had something to do with the DNA that she received from her parents. (She and her brother are well aware that they each have half of my DNA and half of their father’s.) But I thought I could go a little further with this. Hence, a lesson in the Punnett square.
Though I didn’t use Punnett squares to attempt to explain dominant and recessive patterns of inheritance, I did think that working through a few Punnett squares and making some connection to genetics and DNA would be helpful in her understanding of science later on. (I recall learning Cartesian coordinates in school and thinking how easy it was because I grew up playing Battleship.)
Anyway, above are the Punnett squares my four-year-old daughter and I worked through together. She picked the letters and the color and I helped her fill in the squares. She did the last one almost entirely on her own.
UPDATE: I wrote this post more than two years ago. I was inspired to post it here because my son, 6, asked me the same question that she asked: why does he have brown eyes while his twin sister has blue eyes? This time I did attempt to explain dominant and recessive genes while working through a Punnett square. Not sure how much he will retain, but at least the neuronal spark will be there when he learns about it in school.