Imperfect evolution (Introduction)

by Balance_Maintained , U.S.A., Monday, January 19, 2015, 21:40 (3595 days ago) @ David Turell

Heart rhythm disturbances in aquatic diving mammals:
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> http://www.sciencedaily.com/releases/2015/01/150116085554.htm
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> "Instead of a single level of reduced heart rate during dives, the researchers found that heart rates of diving animals varied with both depth and exercise intensity, sometimes alternating rapidly between periods of bradycardia and tachycardia. Cardiac arrhythmias occurred in more than 70 percent of deep dives.
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> "We tend to think of marine mammals as completely adapted to life in the water. However, in terms of the dive response and heart rate, it's not a perfect system," Williams said. "Even 50 million years of evolution hasn't been able to make that basic mammalian response impervious to problems."
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> "The conflict between dive-induced bradycardia and exercise-induced tachycardia involves two different neural circuits that regulate heart rate, she said. The sympathetic nervous system stimulates the heart during exercise, whereas the parasympathetic nervous system controls the slowing of the heart rate during the dive response."-Wouldn't this kind of be expected, though? I mean, to hold your breath for a long time, you have to slow your heart, to exercise, you have have increase your heart rate, so their bodies would have to be balancing the need for both things and under extreme pressure. To me, it would seem that what you would expect to see is that their heart rate would generally slow down and then when needed, for a burst of speed or to counter under water currents and such, that the heart rate would have to kick back up to give a fresh supply of oxygenated blood to the muscles, and then immediately drop back down to allow for continued long dives.-It reminds me of an electric hydraulic motor, or the motor for a pressure washer or generator. They don't run hard all the time. They cycle depending on load.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.