If you ever feel a suspicious rumble underfoot, it’s probably not a skyscraper-sized mutant reptile with atomic breath.
Godzilla, Ghidorah, Rodan, and the other Titans may have been able to take out entire cities because of their size in Godzilla: King of the Monsters, but there is now scientific proof why nothing on Earth is ever going to get that absurdly huge. A Stanford research team that monitored a blue whale’s heartbeat most likely found out why something any bigger could never stomp Tokyo or invade the seas. You couldn’t expect Godzilla to survive when the largest existing creature on the planet gets its heart pushed to the absolute limit.
The objective was to “investigate physiological processes at the extremes of body mass,” Stanford assistant professor of biology and study lead Jeremy Goldbogen and colleagues said in the study, published in Proceedings of the National Academy of Sciences, adding, “From the smallest shrews to the largest whales, physiological performance at the extremes may shed light on constraints to body size.”
What Goldbogen’s team found were some unreal physical extremes. When the whale went under to seek out a meal, its heart rate also took a nosedive, hitting a low of two beats per minute. Less need for oxygen means less stress on the rest of its body at those depths. Heart rate would increase to about 5 beats per minute when it lunged toward its prey and gulped down fish or krill. The highest heart rate, 25 to 37 beats per minute, was measured when the whale broke the surface to breathe. Such unexpected highs and lows told the scientists that the giant’s heart was pushing its limits.
Gargantuan life forms have gargantuan energy needs. This is why, as the team concluded, blue whales must never have evolved beyond a maximum length of 82 feet and weight of 330,000 pounds, never mind Godzilla proportions. The outsize lizard’s latest iteration would be about 394 feet tall and weigh a staggering 164,000 tons. Even Argentinosaurus, the most immense dinosaur (and land animal) ever, couldn’t come close at 70 feet tall and 100 tons. Imagine what its heart could have told us.
Just for comparison, the average T. rex was only 20 feet tall. So much for the hype.
“It seems that near-maximal heart rates are required for gas exchange and reperfusion during their short surface intervals … blue whales likely face several physiological constraints during both the dive interval and the surface interval that may have limited the evolution of maximum body size,” Goldbogen said.
If even such a behemoth as Argentinosaurus had its limits, there is just no way anything could reach the size of Godzilla and actually survive. Your city is safe—for now.
(via Stanford University)