Why Godzilla is too hot to be real
Roxanne Lee, Environmental Science and Policy, 2019
Sixty-five years ago, Godzilla roared into Japanese theaters and the public consciousness and has barely had a day off since. From 1954 onward, the film character, originally conceived as a metaphor for the horror of nuclear fallout, has starred in dozens of films. The changing monster has grown in size over the years, so that in the 2014 American “Godzilla” film it measures 350 feet tall and weighs 90,000 tons — as much as a large cruise ship.
Could there ever be a chance that something of its ilk could stomp onto our shores?
In a 1986 “Journal of Theoretical Biology” study, physicist J.E.I. Hokkanen calculated a theoretical mass limit for terrestrial animals by studying physics and animal locomotion and anatomy. The formula suggests a general mass limit between 110 and 1100 tons. Hokkanen did not rule out the possibility of unique adaptations allowing a creature to exceed the limit, but it would need unique adaptations the like of which we’ve never seen before.
A Godzilla of this size would likely struggle just to live. Large animals in real life have adaptations to mitigate the strain on their bodies. Argentinasaurus, a sauropod dinosaur that measured 120-feet long and 100 tons had four thick legs to disperse its weight, as well as a specially adapted respiratory system. The 200-ton blue whale is supported by water’s buoyancy. Godzilla can swim, but on land has nothing to support it besides two legs, putting a massive amount of strain on its legs, spine, and hips.
The average human at rest produces 100 watts of power. Just at rest, Godzilla’s metabolism would generate 1.4 megawatts, over 1 million times more than a human.
Godzilla could also run into problems with temperature regulation. Mitochondria, the organelles that provide energy for cellular activity, also generate heat. The average human at rest produces 100 watts of power. Just at rest, Godzilla’s metabolism would generate 1.4 megawatts, over 1 million times more than a human, and during activity, up to 37 megawatts, as estimated by the magazine Popular Mechanics. If Godzilla’s cells did utilize mitochondria, it would require specialized anatomy to vent the excess heat.
Even if the physics conundrum of size could be resolved, there is still the issue of finding a food source that could sustain something of that size and energy output. And none of the above even touches on Godzilla’s ability to expel blasts of atomic energy.
Safe to say Godzilla is likely confined to the silver screen. Our cities can rest a bit easier.
Journal of Theoretical Biology (1986). DOI: 10.1016/s0022–5193(86)80167–9
