Con men develop elaborate schemes to cheat people out of their money or other possessions. Successful cons are cleverly and intelligently directed toward the con man's goal. We would not expect such intelligently directed, albeit sinful, behavior in animals, except that the Bible tells us that deceit is the way of the world since sin has entered the creation.
To their surprise, two groups of researchers have discovered a number of animals that try to con their own kind. One group of researchers spent two years standing in ponds, getting to know green frogs. They discovered that when an intruding frog enters a frog community, even the younger males attempt to intimidate him by croaking at a much lower pitch than normal. This makes even the young frog sound like the bigger members of the community, bluffing the intruder. Another team studied Afro-Asian fiddler crabs. When one of the male crabs loses its claw, it will grow back, only slowly. So the crab quickly grows a fake claw until the new one grows in. The fake claw is useless for fighting, but works well in aggressive claw waving at other males. It can also be used in the claw waving that is part of the crabs' mating ritual. Females prefer the fastest-waving claws, so the lighter fake claws, which wave faster, are a real advantage.
While animals cannot be charged with sin, we are responsible for our actions. We thank God that he has sent His Son to save us from the guilt of our sins.