Imperfect evolution (Introduction)

by David Turell , Monday, January 19, 2015, 22:03 (3595 days ago) @ Balance_Maintained

David: 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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> Wouldn't this kind of be expected, though? -No, they are talking about arrhythmias, in cardiologic parlance 'abnormal rhythm' What they were seeing was abnormally slow rhythms and abnormally fast ones, not fitting the activity. We humans have a dive reflex which slows your heart as you hit the water. In rare circumstances it has killed.
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> Tony: 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.-Here you are describing normal cardiac activity related to exercise. There is a direct correlation between calorie work load and pulse rate different for each individual based on their state of fitness, with a maximal rate limited by advancing age.