In Breath-Holding, Kate Winslet and a Croc Are Champions
Recently, the Wall Street Journal reported that Kate Winslet, and other actors, for the sake of “the newest frontier in blockbuster moviemaking” are learning how to hold their breath underwater for several minutes.
Around the same time the website Science Daily highlighted an article from Current Biology that expounded on “how crocs can go hours without air,” thus blowing Miss Winslet’s impressive feat — seven and a quarter minutes holding her breath — right out of the water. The article attributes this croc ability to evolution.
But things are not as simple as they look. This is especially true once you understand how life works to survive, and the causal hurdles that would have had to have been surmounted to build life from the ground up.
That’s what my recent book, co-authored with Steve Laufmann, Your Designed Body, accomplishes for the reader. Read the book and you’ll be prepared to analyze the validity of Darwinism, ask evolutionists better questions, and expect better answers rather than just accepting their “just so” stories.
As Steve and I demonstrate, with each lesson learned about the complexity of life and survival and the built-in engineering that makes that possible, the explanatory power of Darwinism fades away until all that is left is the narrative gloss.
Reviewing the Basics
The fundamental building block for all life is the cell. One of the cell’s most important needs is energy. The cell, whether it lives and works in Kate or the croc, mostly gets this energy from cellular respiration. Cellular respiration involves the cell, in the presence of oxygen, releasing the energy from within the glucose molecule (while producing carbon dioxide) and storing it as ATP (the cell’s energy currency). The cell does also have a much less efficient way of getting a lot less energy from glucose, called glycolysis, a process that is anaerobic in that it does not require oxygen.
A one-celled organism, such as an amoeba, is like an “island of life.” That’s because it can get what it needs from its watery environment, while getting rid of what it doesn’t need as well. When it comes to energy, the amoeba gets its glucose and oxygen from its surroundings and releases carbon dioxide.
In contrast, a multi-cellular organism, like Kate or the croc, is like “a deep dark continent of life” since almost all of its trillions of cells are not near its surroundings. That’s why the organism needs to have a respiratory system to bring in oxygen (and release carbon dioxide), a gastrointestinal system to bring in glucose, and a cardiovascular system to carry these chemicals in the blood to or from all of the cells.
Not having enough oxygen (or for that matter, glucose) for your cells, especially the ones in the brain, which affords consciousness and controls breathing and the cardiovascular system, is a quick path to death. So, understanding how a creature can perform these breath-holding feats, while staying alive, is not an exercise in abstraction.
Physicians and engineers, unlike evolutionary theorists, work in the real world of science. The end point that proves any of their thought or practical experiments to be wrong is death — whether it’s that of the body or of a machine. That’s why understanding why an organism has to have enough oxygen (and anything else it needs to survive) and what happens when it doesn’t (death) must be plugged into any theory of life. Without this grounding in real “life and death” science, evolutionists are just letting their imaginations run wild.
Trillions of Cells
By hyperventilating beforehand, Kate Winslet maximized her blood level of oxygen and minimized her blood level of carbon dioxide. While holding her breath, as her carbon dioxide level rose and her oxygen level dropped, she would have had to resist the urge to breathe and also deal with symptoms like “tingling limbs, impaired vision, feelings of freakout” while being at risk of becoming unconscious and drowning. That’s why she always did this under the supervision of a trainer. Do not try this at home or alone!
The Cardiovascular System
Besides her respiratory system, putting oxygen into her blood to get it to all the cells in her body, Kate has a cardiovascular system. This consists of the heart with its right and left sides, and the pulmonary and systemic circulations. The right ventricle pumps deoxygenated blood through the pulmonary arteries to the lungs where it enters the capillaries surrounding the alveoli to pick up oxygen and then returns to the left side of the heart through the pulmonary veins. The left ventricle pumps oxygenated blood through the systemic arteries to the capillaries in the tissues. There, the cells get the oxygen (and glucose) they need and download the carbon dioxide. The blood then returns to the right side of the heart through the systemic veins.
One final problem remains, though. It turns out that oxygen doesn’t dissolve well in water. That’s why Kate Winslet has hemoglobin that’s made in her red blood cells, which are made in her bone marrow. Hemoglobin is a complex molecule, containing iron, that locks onto oxygen when it enters the blood from the lungs and so allows the blood in the body to have enough oxygen-carrying capacity.
With maximum exercise, Kate’s body needs a 14-fold increase in oxygen consumption compared to when she’s at rest. This means that her blood has to have enough red blood cells with enough hemoglobin to carry enough oxygen to meet the metabolic needs of her body, no matter what she’s doing. So, that means that her body has to control her hemoglobin.
As noted, every control system needs at least three parts and the one that controls the hemoglobin is no different. Kate has specialized cells in her kidneys that sense her blood level of oxygen and in response, the cell as the integrator sends out a certain amount of a hormone called erythropoietin. Erythropoietin travels in the blood and attaches to specific receptors on immature
stem cells in the bone marrow and tells them to develop into red blood cells, which produce hemoglobin. So, if the oxygen level goes down the kidney cells send out more erythropoietin which tells the bone marrow to make more red blood cells which gives the body more hemoglobin.
Given her impressive feat, it’s safe to say that Kate Winslet’s respiratory, cardiovascular, and hematological systems were all working at maximum efficiency. But the croc can easily beat her. Now, remember, the croc needs this functional capacity for survival. He’s not worrying about performing well enough to meet the needs of “the newest frontier in blockbuster moviemaking.” Nor is he trying to impress his friends by showing them how long he can hold his breath underwater while risking death by drowning. No, when the croc grabs the hindquarters of an antelope, he instinctively dives down deep into the water, where he knows he can survive for an hour or two without drowning, but the antelope can’t.
Since this involves the respiratory, cardiovascular, and hematological systems, they would seem to be the right places to start in comparing Kate and the croc. But before we do, we have to take into account that Kate is warm-blooded, while the croc is cold-blooded.
Hot and Cold
This difference means that Kate has to use a lot more energy (oxygen) than the croc to maintain her core temperature, which is between 97o and 99o F. She needs to do this so that all of her organ systems, especially her brain, can work properly. Remember, the croc only has to worry about surviving and reproducing. It would seem that being cold-blooded doesn’t bother his self-esteem one bit. However, being warm-blooded allows us to have the biggest brains in the animal kingdom, a fact that affords us numerous abilities, like intelligence, reasoning, creativity, self-reflection, and free will, going far beyond mere survival and reproduction.
In contrast to Kate Winslet, the croc can usually maintain its core temperature, between 82o and 92o F, with little effort simply by making sure it lives in a warm climate. In fact, at rest the croc only uses about 15 percent of the energy that a human does. And when it dives down deeper where the temperature is lower, because it is cold-blooded, it is able to reduce its metabolic rate even further.
So, for a given ambient temperature and level of activity, the croc requires much less oxygen (energy) than a human does to survive. This is so even if the human and the croc have the same amount of oxygen available for use. In fact, it means that as compared with Kate, the croc can get by on the anaerobic process of glycolysis to obtain the limited amount of extra energy it provides because he only needs 15 percent of what Kate needs.
From the start we can see that since the croc uses much less oxygen per minute than does Kate, this would at least partially explain why it is able to hold its breath under water so much longer. But there’s more. On Monday we’ll ask, “How Does the Crocodile Hold His Breath So Long?” Stay tuned.
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