Caloric Requirements of Superheroes

By Scott Mattison (@FoolsPizza)

The average person burns around 2000 calories a day. This approximation is found on pretty much every food wrapper when they provide your “estimated daily values”. Superheroes aren’t average people and likely need an above average caloric intake. Below are some very basic approximations to determine the number of Calories a superhero burns when using their power for 1 minute

Number of Calories burned per minute by various superheroes.

If you are still reading, you are probably curious how I came up with these values. So let’s go through them based on their powers. First of all I should probably define what a Calorie is. Calories are a unit measure of energy and Calories as reported on food are actually 1000 calories (with a lower case “c”). 1 calorie is the energy required to raise the temperature of 1 gram of water 1 degree Celsius.

Flash & Dash

Both Flash and Dash’s caloric requirements are based on estimated VO2 maximum converted to Calories. VO2 max is the measurement of the maximum possible oxygen that may be utilized during exercise. I estimated VO2 max using ACMS running VO2 equation which provides a very rough approximation based on body weight, speed, and incline.  So to calculate VO2 max, I needed to first find the top speed of Flash and Dash.

The Flash’s top speed varies wildly in the comic books, sometimes being shown as capable of running faster than the speed of light other times he has a maximum speed around Mach 3 (three times the speed of sound, or 1029 m/s).

Dash is a bit harder to estimate as there is much less data to work from, but I based my estimation on the scene in “The Incredibles” where Dash gets caught on camera placing a tack on the teacher’s chair. The camera which is likely updating between 24 and 30 frames per second and Dash traverses the distance from the back of the room to the teachers desk and back (roughly 30 feet) within one camera frame so I estimate Dash’s top speed to be 220 m/s. This is reasonable as we never see Dash break the sound barrier in either Incredibles movie.


Wolverine was probably the hardest to estimate and is most likely the most incorrect of all of my approximations; however, if anything, this estimate is low. Wolverine’s primary power is a healing factor that allows him to recover from almost any injury. The speed at rate his healing factor works is a little bit of a debate, so I have to make some assumptions. I settled on the assumption that Wolverine can heal a broken bone in a minute. (This is obviously a little silly since his bones are practically unbreakable due to the Adamantium bonded to them).

The energy expended by the body due to injury is also difficult to estimate, but many sources recommend an increased intake of 400-500 Calories per day while healing from a broken bone and it takes 6 – 8 weeks for the body to repair a minor fracture. Thus it takes ~16800 Calories for the body to repair a broken bone.


Batman may not have any super powers (except maybe always having a plan somehow), but he is trained in several forms of hand to hand combat. A quick search estimates that a high intensity martial arts session may burn up to 960 Calories in 30 minutes.

Jean Grey

Jean Grey’s powers of telepathy allow her to lift objects with her mind. Lifting any object requires energy in the form of weight of the object multiplied by the height the object is lifted. When not The Phoenix, Jean Grey has demonstrated the ability to lift objects up to nearly 50 tons. Assuming she lifts this weight at a rate of 10 meters per minute (possibly a low estimate) this would required 1063 Calories of energy.

Bonus: Scott Summers aka Cyclops

This blog post was originally conceived around the idea that Cyclops’ optic blasts would require an insane amount of energy to sustain. However, during my initial research I learned that Cyclops is not actually emitting lasers from his eyes, but is instead opening an aperture to another dimension and allowing energy from that dimension to enter ours. So yeah, you learn something new every day. However, going with my original idea, what would happen if someone like Cyclops existed that could actually emit lasers from their eyes (like Superman, but not solar powered).

Cyclops’ optic blasts emit 2 Gigawatts of energy (2 * 109 Joules/second). There are 4184 Joules in a Calorie, which means that in one minute, our Cyclops equivalent would burn 28680688 Calories

Do Professor Xavier and Magneto Have the Same Base Power?

By Scott Mattison (@FoolsPizza)

Before we dive into this, I must first admit that I am not an avid reader of the X-men comics; however, I have really enjoyed a lot of the X-men movies, specifically X-men: First Class. Throughout the X-men series, Charles Xavier and Eric Leschner have often been depicted as two sides of the same coin, both working to further the cause of mutants. Xavier believing that advancing the mutants’ cause must be done (mostly) through working with humans and finding common ground; whereas Magneto believes that mutants and humans are destined to be enemies that mutant rights can only be ensured through force. I am sure there are many others out that could have a much more thorough discussion regarding the symbolism and underlying messages that are rooted the relationship between these two characters; however, I am here to pose a much more important theory. Magneto and Professor Xavier share the same base ability: the manipulation of magnetic fields.

Magneto and Charles Xavier discussing their world views. All Marvel characters and the distinctive likeness(es) thereof are Trademarks & Copyright © 1941–2018 Marvel Characters, Inc. ALL RIGHTS RESERVED.

I am not going to waste time arguing that the manipulation of magnetic fields is Magneto’s power, it is literally in his name! Now for the harder one, Charles Xavier.

In the X-men comics Professor Xavier is depicted have the ability to both read the minds of others as well as implant thoughts into the brains of others through what is known as telepathy. Telepathy is the communication of thoughts and ideas between individuals without the use of the traditional senses. Most of you are thinking Charles Xavier is a known telepath, how you could possibly argue that manipulation of magnetic fields is his power? The answer to this question are two fundamental laws of physics, Ampere’s Law and Faraday’s Law of Induction.

Let’s start with Ampere’s Law. Ampere’s Law defines the generation of magnetic fields due to electricity. Ampere’s Law states that magnetic fields may be generated by the motion of an electrical current or by changing electrical fields.

Our thoughts are complex firings of neurons within the brain, transferring electrical potentials from one brain cell to another. One way scientists study the brain is by tracking these electrical potentials through what is known as electroencephalography (EEG). An alternative to EEG is called magnetoencephalography (MEG) and tracks the small magnetic fields generated when neurons are communicating. This is a practical application of Ampere’s Law. From this, we see two possible ways that Charles Xavier could be telepathically reading the minds of others, either through interpretation of the electric fields (similar to a really fancy EEG) or the interpretation of the magnetic fields (a really fancy MEG). We still do not know how he could possibly place thoughts into the minds of others.

An illustration of the the relationship between electricity and magnetism. The arrows represent the magnetic field generated by the current moving through a wire wound around a center axis. The circles represent the cross section of a wire. Source: Wikipedia

For the answer to this, we go back to physics, our good friend Faraday, and his law of induction. Faraday’s Law of Induction states that any change in the magnetic environment of a coil of wire will cause a voltage to be induced in the coil. This means that by changing a magnetic field, we can actually cause the generation of electricity. If the firing of neurons is just changes in voltage potentials across the neuron cells, this means that a magnetic field could cause a neuron to fire.

In fact, this has been demonstrated in medical science. The FDA actually places limitations for how fast the magnetic field inside of an MRI machine can change to prevent muscle spasms in patients.Additionally, there are new fields treatments for depression and anxiety being developed that use targeted magnetic fields to stimulate regions of the brain. So far, these approaches have been shown to be highly targeted and extremely safe. (Author’s Note: MRI machines are extremely safe and none of the discussed technologies could in anyway control your mind).

Scientists are still working to map the complex neural interactions that occur in the brain. While research has begun to be able to map out emotional responses and regions of the brain linked to various types of thought, we are still a long way from reading someone’s mind. However, despite current limitations of science, by combining the concepts of Faraday’s Law and Ampere’s Law we can see that Professor Xavier could gain the abilities of telepathy from a very precise control and interpretation of remote magnetic fields. Of course there are alternate interpretations, Xavier could easily be manipulating and reading the electrical fields in the brains of others. Perhaps more concerning is that regardless of whether or not Xavier can control magnetic fields, with a little practice Magneto could definitely gain the abilities of telepathy.

How do we Hear?

By Scott Mattison (@FoolsPizza)

Hearing is one of the five traditional senses, but by the time individuals reach 60 years old, one in three will develop significant hearing loss in one or both ears. To treat this hearing loss, we must first have a basic understanding of how sound and our hearing work.

Sounds travel by mechanical vibrations of particles that contact one another. Air, water, and solids all allow for these vibrations to occur; however, in space, no one can hear you scream because outer space is a vacuum with no small particles to transfer sound (sorry Star Wars fans).

The ear is divided into three regions: the outer ear, the middle ear, and the inner ear. The outer ear is what is most familiar to people, it consists of what we traditionally call ears and a canal that leads to the eardrum. The role of the outer ear is to collect sound and direct it to the middle ear through the ear drum. The unique shape of the ear enables directed sensing of sounds which gives people the ability to determine where sounds come from.

A nice illustration of the middle ear bones (ossicles). Courtesy of Wikipedia.

The middle ear is an open, air filled space in the skull that separated from the outer ear by the ear drum. The active portion of the middle ear consists of three bones known as the malleus, incus, and stapes. The malleus is attached to the eardrum, and when the eardrum vibrates in response to sounds, those vibrations are transferred to the malleus. Movements of the malleus move the incus, which in turn move the stapes. The stapes then vibrates against what is called the oval window of the inner ear. The bones of the middle ear form a lever arm that provides an amplification of sound by around 130%. Additional amplification occurs due to the size difference between the eardrum and the oval window of the inner ear. Overall, sound vibrations entering the inner ear are around 18 times larger than sound vibrations against the eardrum. The middle ear also has special muscles that when activated will reduce the intensity of loud sounds. This is called the acoustic reflex and may reduce sound intensity by around a factor of 10. The acoustic reflex protects the delicate structures of the inner ear.

The inner ear is where all the magic of hearing happens. The inner ear takes the mechanical vibrations of sounds and converts them into electrical impulses within the brain. How this actually works is both a lot cooler and a lot more complicated than it might seem.

At their best, humans can hear a range of sound frequencies (think notes on the piano, each note is a different frequency) between 20 Hz and 20,000 Hz. 20 Hz is a really deep bass sound and 20,000 Hz (If you can still hear it) is an extremely high pitched whine. As we age, sensory cells in our inner ear begin to die and we lose the ability to hear higher pitched frequencies. By age 20, most males have lost the ability to hear 20,000 Hz, females typically begin to lose higher frequency hearing later into their twenties. Fortunately most of human communication is limited to the 100s of Hz frequency range. The fact that we can differentiate between sounds of different frequencies means that our inner ear has to respond differently to different sound waves.

Nervous cells have a recovery period of 1 – 5 ms after each time they fire, meaning the fastest a nerve could respond is 1000 Hz. If this is true, how can our ears generate nervous signals in response to sounds vibrating up to 20 times faster? The answer to this question is a fun word: Biomechanics. The inner ear, known as the cochlea, consists of 3 fluid-filled tubes that spiral up to a blind end. Typically this is drawn as its own snail-shaped solid, but in reality the cochlea is a fluid filled cavity with the temporal bone of the skull. Sounds enter the cochlea through the oval window into the bottom of the 3 tubes. Sound waves travel to the top of the spiral of the cochlea then back down through the top tube and vibrate against the oval window. This top tube and bottom tube mainly play the role of sound conductor; the nervous tissue is all sitting within the middle tube.

Inner Ear
A rough sketch of the cochlea with the spiral stretched out into a strait line. Sound waves enter through the oval window.  Higher frequency sounds are propagated through the basilar membrane toward the start of the cochlea whereas lower frequency sounds pass through the basilar membrane toward the end.

Between the bottom tube and the middle tube is what is called the basilar membrane. This membrane has changing mechanical properties all the way down its length so that at the entrance of the cochlea it vibrates strongly in response to higher frequency sounds and at the top of the spiraled cochlea the basilar membrane vibrates best in response to lower frequency sounds. Nervous cells in the inner ear respond to the movement of the fluid within that middle tube so when the basilar membrane vibrates more strongly due to higher frequency sounds at the base of the cochlea, the nervous cells in that region know to tell the brain that you just heard a high pitched sound. And when nervous cells respond to movement in the upper part of the cochlea, the brain knows you just heard a lower pitched sound.

An illustration of what is known as the organ of Corti. This rests on top of the basilar membrane and plays a large role in our hearing. Image source: Wikipedia.

The basilar membrane is a really cool example of biomechanics in of the body solving complex challenges, and Georg von Békésy even won the Nobel Prize in Physiology or Medicine in 1961 for his work in in demonstrating its function. However, movement of the basilar membrane alone does not completely account for how well the hearing of humans and other mammals can tell the difference between two frequencies. This is the role of the organ of Corti, which I will introduce in a later blog post. Obviously, there is a bit more to the inner ear than I have explained here, and this is an exciting question for which scientists are still exploring answers!


Are Koopas Sex-Role Reversed?

By: Andrew Anderson (@AndersonEvolve)

In my previous post, I presented what koopas are and what forms (phenotypes) are considered the same species.  Of course, after the post I found this page, which lists what character types are within the koopa species complex.  The bad news is I missed a couple—I had no idea there were so many Mario games. The good news is the ones I designated as koopas are on the list and honestly it’s all made up anyways.  In addition, the groups I failed to include aren’t necessary to determine the parental and mating system of koopas.

The first question—what kind of parental care do koopas have?— is straightforward in its answer:  male brood care. Running down the list of familial relations and we see Koops has a father, Koopley, Kolorado has a father, Koopa Krag is a grandfather, and Bowser is just a prolific father.  Notice something missing? No mention of mothers. Even Baby Bowser’s caretaker is Kamek. Now we can debate as to how dedicated these fathers are since most of the time the father is absent, but in most cases the father has some interest in the well-being of his children.  We do know female koopas exist, so why aren’t they seen with offspring? Quite simply, females don’t participate in broodcare, leaving males with those duties. It is true we can’t sex most koopas, but I think that’s because they haven’t reached maturity yet and address that below.  Such a conclusion means that the Koopa Troop is sending young koopas into battle that Mario mercilessly pounds on.

The next question—which sex is under stronger sexual selection (more intense competition for mating and producing offspring)?—is a bit more challenging to answer.  There has been some discussion among biologists about how best to measure and determine sexual selection, but this paper has a good description and mathematical explanation for those who want a little more. I’ve gone over the various things known about koopas and honestly can’t come to a certain conclusion, so I’ll just lay out the evidence for both sides.

Typical sex-roles–Stronger Male Sexual Selection

There are three pieces of evidence that supports the typical sex-roles for koopas.  The first is the variance in reproductive success. Bowser has a bunch of kids, while the other known fathers seem to just have one.  Unequal reproductive output creates opportunities for sexual selection. Bateman proposed that males mating with more females lead to more offspring, but more matings does not produce more offspring in females.  A quick glance across all of Bowser’s kids from Mario 3 and there is a wide variety of forms, suggesting that they may have different mothers. There seems to be some male koopas who mate A LOT, some who mate a little, and some who don’t mate; a clear indication that males could be under sexual selection.

Male koopas with maturation (secondary sex?) trait of hair. Notice the prolific Bowser’s luxurious locks. Left:  Koopley–Koops father, Top:  Koopa Krag, Bottom:  Bowser

The other evidence is koopas seem to have secondary sexual characteristics.  Look at the known fathers in koopa-dom and the non-fathers. Notice that the fathers have hair, I propose that hair is a trait that shows the males are ready to mate, much like antlers on deer.  Now, there are koopas with hair that don’t have any (known) offspring, but it could be that they are in mating condition but have not found a mate or produced any offspring yet. The more important aspect is there are no successful males without hair.  While there are other traits, like a spiked shell and horns that Bowser has, no other fathers have them and there are other koopas that posses spikes and horns without children, so these traits may not play a role in reproductive success (Bowser is attractive because of his long flowing hair).

Koopas without hair and no known offspring. None of these koopas are mature.

Lastly, the dearth of females suggests the sex ratio is tilted towards males.  In cases where one sex is rarer than the other,the rare sex is able to be choosier about their mate, putting selection on the majority sex.  In most species the split of sexes is 50/50 so the better descriptor is Operational Sex Ratio (OSR) and it counts only individuals who are reproductively available. If one sex takes longer to mature or is engaged in broodcare/pregnancy, it doesn’t count.  Even though male koopas take part in broodcare, Bowser demonstrates that they can brood from multiple females so they aren’t removed from the OSR calculation (something that is common in fishes).

Reversed Sex-Roles: Stronger Female Sexual Selection

So while I have assumed Bowser has lots of kids from multiple females, it is currently Nintendo’s stance that he only has one child–Bowser Jr.  Personally, I disagree since the Koopa Kids and the Koopalings have been called his children in previous games. In any case, if Bowser only has one child then the variance in offspring across males drops precipitously.  Now the number of children any male koopa has is either 1 or 0, which isn’t much variance. In this case, the males don’t seem to get more offspring from multiple females (i.e., little opportunity for sexual selection). This doesn’t mean females are higher, but it certainly undercuts the evidence for males.

Koopalings.  Notice the wide variety of forms.  It seems unlikely that all were made from the same pairing.

Alternatively, Bowser could be cuckolded with the possibility he was given all his children by one female although not all of them he sired.  This is known to happen in some polyandrous (multiple males one female) mating systems such as sandpipers and jacanas. The result is Bowser mated with one female, who mated with multiple males, that gave him seven eggs (the Koopalings) for him to care for.  Certainly if you were to look at all the Koopalings many of them bear little resemblance to the King of Koopas. Without genetic tests, we have no way to know the true parentage and thus the mating system for sure–although it would make for a great Maury episode.

Female Koopas.  From Left to Right and Top to Bottom:  Pom Pom, Koopie Koo, Wendy O. Koopa, Lakilulu, Kammy Koopa, Holly Koopa, Kylie Koopa.  Notice the females with hair either have a mate or are considered mature. 

Just as reproductively active male koopas have hair, it appears females have the same trait to indicate maturation.  Take a look at the 7 named female koopas: Koopie Koo, Lakilulu, and Pom Pom all have boyfriends and have hair. Holly, Kylie, and Wendy O Koopa are not shown with love interests and do not have hair.  Kammy Koopa has hair and has no shown boyfriend, but given her apparent age she is likely mature. Since both males and females have hair it can’t be a secondary sex trait (it has to be different between the sexes to be a sex trait), but it can be a sign of maturation.  

Both Lakilulu and Koopie Koo are extremely protective of their boyfriends, perhaps this is similar to mate guarding if females are under stronger selection.  While Koopie Koo’s boyfriend, Koops, is not mature (no hair), she encourages him to adventure and come back a stronger koopa. It may be she has secured a mate and wants to be sure he is ready to provide care, a long term strategy if ever there was one.  So why are the female so protective of their mates? We can go back to the operational sex ratio; if males are engaged in brood care and not many are mature yet (very few have hair) then there are less males than females available for mating thereby forcing females to protect the mates they have found.

I would like to point out that it is entirely possible, and even not uncommon, for both sexes to experience sexual selection.  When we talk about the roles though, we are asking which sex undergoes greater selection than the other as that can drive how evolution works.  While I’m not certain, I would like to think the females are under stronger selection; but then again I work with reversed species so I’m biased.  What do you think? Sound off on our twitter @SciSidequests!!

What Does it Mean To Be a Biomedical Engineer?

By Scott Mattison (@FoolsPizza)

In typical engineer fashion, instead of introducing myself and my field, I jumped in head first and published a few more technical articles. I am a young professor of Biomedical Engineering, and one basic question I am often asked is, “What is a biomedical engineer?” Surprisingly, this is a much more difficult and nuanced question to answer than it may seem.

We can start with the technical answer: as with most fields, biomedical engineering is a very broad discipline and has many different sub-specialties within it. Biomedical engineers might design prosthesis, improve instrumentation for hospitals, work in pharmaceuticals, develop physiological models, and even research artificial organs.

Biomedical Engineering
A sampling of the many different sub-disciplines of Biomedical Engineering. The Biomedical Engineering Society does an excellent job discussing a lot of these disciplines.

To meet the broad demands of their field, many degree programs in biomedical engineering provide their engineers with a broad engineering background in their first few years of school gaining skills in electrical and mechanical engineering as well as biology. As they progress through their degrees, biomedical engineers begin to focus their education into increasingly specialized backgrounds, which gives them a strong knowledge foundation in many fields and enhanced knowledge in their specialty.

Obviously, education is really only a small part of what defines a field. In the workplace, engineers wear many hats. Biomedical engineers have the technical knowledge and skills to work in most specialized engineering fields (electrical, mechanical, etc.), but also have the medical and scientific knowledge to communicate with doctors and researchers. This means that biomedical engineers get to bridge the gap between engineering and practice and apply their skills to two equally exciting, yet fundamentally different, fields.

Now that the technical answer is out of the way, I want to convey the more practical answer to this question. There is always a unique distinction between engineering and science, and biomedical engineers walk this line more than most. The rationale for this distinction is that the typically science seeks to develop knowledge and understanding of the physical universe whereas engineering attempts to apply scientific knowledge to the needs of society. To me, the line between science and engineering is actually rather blurry. No work exists in a vacuum and someone seeking to developing knowledge is often going to have an application for that knowledge in mind.

Biomedical engineering is a prime example of the interdependence of science and engineering. Scientists discover exciting new information about physics, chemistry, or biology and engineers turn these discoveries into new technologies which further feed scientific discovery and apply those discoveries toward tangible benefits. No one can  guess where the next big discovery will come from, and seemingly insignificant finds in science can eventually lead to huge breakthroughs in engineering (and vice-versa). Of course, this interplay does not merely exist between engineering and science but among and within various fields of science, wherein all discoveries feed into our bigger understanding of the world.

While I could continue to elaborate about the importance of collaboration between fields, I admit that I have deviated from my initial question: What does it mean to be a biomedical engineer? As a biomedical engineer, I personally feel a calling to not only perform innovative research in the fields of biology and medicine, but also to enhance the capabilities of the research projects of my peers. This feeds into my work in biomedical optics, where I develop new optical systems to study processes that I find fascinating as well as attempt to provide my peers with novel ways to obtain information about micro anatomy and cell organization.

It should be noted that this is merely my personal definition and is not the only possible one. Nearly any path may eventually lead people to the field of biomedical engineering; indeed, my graduate school mentor has a Ph.D. in Chemistry, but is clearly a biomedical engineer. In reality, anyone who is using engineering design techniques and processes to solve challenges in the fields of biology and medicine is working as a biomedical engineer.

Welcome to Scientific Sidequests

Scientific Sidequests was started by a group of biological scientists from diverse fields who shared common interests in games, movies, and shows.  Of the many things we enjoyed when together playing a game or watching a movie was hearing and discussing what the others were doing and working on in fields just beyond our own.  We each also brought our own perspectives from our disciplines that led to many interpretations of shared experiences. The hope we all have with Scientific Sidequests is to bring those different perspectives to one place and have anyone with a curious mind view the amazing breadth of biology.