Scientists Record a Blue Whale's Heart Beat for the First Time Ever, Results Leave Them Stunned

Seven years ago researchers followed a California whale to find out his heart rate and were surprised to witness the variance. As per their records, the whale survived on just two beats per minute in the depths of their water habitat, which then changed to 30 beats per minute when closer to the surface, Live Science stated. Experts believe that this data gives an idea regarding the physical limits of earthly creatures. Findings regarding this variance of heartbeats have been recorded in the journal Proceedings of the National Academy of Sciences. 

For this study, experts chose a male whale from a group living in Monterey Bay, California. This whale was selected because of its unique position of being the only male in the group. He was the first male whale that experts had noted in the area. A sensor was attached to the mammal with the help of a 20-foot-long pole (6 m). This sensor was made of plastic and comprised of four suction cups. In two of the cups, experts added electrodes to measure the mammal's heartbeat. During the first exercise, the sensor remained with the whale for 8.5 hours. In this period the whale went out on many food-foraging missions, diving up and down in the water. His longest dive lasted for 16.5 minutes and the maximum depth he swam underwater was 600 feet (184 m). Researchers claimed that the subject did not spend more than four minutes at the surface during this period. 

The sensor revealed that when the whale reached closer to the depths, his heartbeats ranged from four to eight times a minute on average. The lowest heart rate recorded by researchers during this period was two beats per minute. This data was 30 to 50% lower than what researchers expected. Scientists believe that during the lower trajectory of heart rate, the whale's aortic artery stretched itself in such a manner, that the oxygenated blood moved slowly throughout the body. When the whale reached the surface, the heart rate shot to 25 to 37 beats per minute. The artery adjusted itself in such a way, that oxygen was able to quickly engulf the bloodstream providing enough energy to the mammal for the next dive. 

Seeing the heart rate patterns, researchers concluded that while trying to reenergize himself on the surface, the whale is working close to its physical limits. This means that the whale's heart could not beat faster. This explains why whales stop growing after attaining a certain size. Experts further think that the highest heart rate of whales could be the top limit for any being on the planet. This assertion came from the fact that whales till now are considered to be the largest beings on Earth. For a faster heart rate, the creature would need to be larger than whales. Therefore, at present no being could have a higher heart rate than these mammals, as per researchers. Experts were delighted by the results of the study as it helped them understand the limits of creatures on Earth. "Animals that are operating at physiological extremes can help us understand biological limits to size," lead study author Jeremy Goldbogen, an assistant professor at Stanford University in California said.