142 P H V SIC S OF THE IMPOSSIBLE
Hollywood, however, probably gets it right when it depicts intelligent alien life-forms as carnivores. Not only do meat-eating aliens
guarantee bigger box office sales, there is also an element of truth to
the depiction. Predators are usually smarter than their prey. Predators
have to use cunning to plan, stalk, hide, and ambush prey. Foxes, dogs,
tigers, and lions have eyes that are on the front of their face in order to
judge distance when they pounce on their prey. With two eyes, they
can use 3-D stereo-vision to lock on to their prey. Prey, such as deer
and rabbits, on the other hand, just have to know how to run. They
have eyes that are on the side of their face in order to scan for predators 360 degrees around them.
In other words, intelligent life in outer space may very well evolve
from predators with eyes, or some sensing organ, on the front of their
face. They may possess some of the carnivorous, aggressive, and territorial behavior we find in wolves, lions, and humans on Earth. (But
since such life-forms would probably be based on entirely different
DNA and protein molecules, they would have no interest in eating, or
mating with, us.)
We can also use physics to conjecture what their body size might
be. Assuming they live on Earth-sized planets and have the same
rough density as water, like life-forms on Earth, then huge creatures
are probably not possible because of the scale law, which states that
the laws of physics change drastically as we increase the scale of any
object.
MONSTERS AND THE SCALE LAW
If Ring Kong really existed, for example, he would not be able to terrorize New York City. On the contrary, his legs would break as soon as
he took a single step. This is because if you take an ape and increase
his size by 10 times, then his weight would go up by the increased volume, or by 10 x 10 x 10 = 1,000 times. So he would be 1,000 times heavier. But his strength increases relative to the thickness of his bones and
muscles. The cross-sectional area of his bones and muscles goes up by
Hollywood, however, probably gets it right when it depicts intelligent alien life-forms as carnivores. Not only do meat-eating aliens
guarantee bigger box office sales, there is also an element of truth to
the depiction. Predators are usually smarter than their prey. Predators
have to use cunning to plan, stalk, hide, and ambush prey. Foxes, dogs,
tigers, and lions have eyes that are on the front of their face in order to
judge distance when they pounce on their prey. With two eyes, they
can use 3-D stereo-vision to lock on to their prey. Prey, such as deer
and rabbits, on the other hand, just have to know how to run. They
have eyes that are on the side of their face in order to scan for predators 360 degrees around them.
In other words, intelligent life in outer space may very well evolve
from predators with eyes, or some sensing organ, on the front of their
face. They may possess some of the carnivorous, aggressive, and territorial behavior we find in wolves, lions, and humans on Earth. (But
since such life-forms would probably be based on entirely different
DNA and protein molecules, they would have no interest in eating, or
mating with, us.)
We can also use physics to conjecture what their body size might
be. Assuming they live on Earth-sized planets and have the same
rough density as water, like life-forms on Earth, then huge creatures
are probably not possible because of the scale law, which states that
the laws of physics change drastically as we increase the scale of any
object.
MONSTERS AND THE SCALE LAW
If Ring Kong really existed, for example, he would not be able to terrorize New York City. On the contrary, his legs would break as soon as
he took a single step. This is because if you take an ape and increase
his size by 10 times, then his weight would go up by the increased volume, or by 10 x 10 x 10 = 1,000 times. So he would be 1,000 times heavier. But his strength increases relative to the thickness of his bones and
muscles. The cross-sectional area of his bones and muscles goes up by