Using a bright orange electrocardiogram machine attached with suction cups to the body of a blue whale, scientists for the first time have measured the heart rate of the world's largest creature and came away with insight about the renowned behemoth's physiology. From a report: The blue whale, which can reach up to 100 feet (30 meters) long and weigh 200 tons, lowers its heart rate to as little as two beats per minute as it lunges under the ocean surface for food, researchers said. The maximum heart rate they recorded was 37 beats per minute after the air-breathing marine mammal returned to the surface from a foraging dive. "The blue whale is the largest animal of all-time and has long fascinated biologists," said Stanford University marine biologist Jeremy Goldbogen, who led the study published in the journal Proceedings of the National Academy of Sciences. "In particular, new measures of vital rates and physiological rates help us understand how animals work at the upper extreme of body mass," Goldbogen added. "What is life like and what is the pace of life at such a large scale?" Generally speaking, the larger the animal, the lower the heart rate, minimizing the amount of work the heart does while distributing blood around the body. The normal human resting heart rate ranges from about 60 to 100 beats per minute and tops out at about 200 during athletic exertion. The smallest mammals, shrews, have heart rates upwards of a thousand beats per minute.