Survival of the fittest, the conqueror gets the plunder, the strong overpowers the weak.
A gecko preying on a common house lizard.
The picture portrays a very basic instinct among animals. Darwin described this in his Theory of Natural Selection. Those fit to survive, or those who are able to adapt well in its environment, are the ones populating the earth. The crocodiles have survived for 200 million years because of their ability to adapt despite significant changes in their environment and lately, pressures of anthropogenic nature. Scientists explained that this is primarily due to the reptile’s opportunistic behavior, grabbing its prey when the prey is unwary of its presence. It keeps itself in low profile, not obviously making signs to indicate its presence. In Palawan, Philippines, for example, I never suspected that crocodiles were present among the mangroves and along rivers until I did night surveys (I was a crocodile researcher then) using a spotlight and saw crocodiles, their eyes flashing red along the river.
Opportunistic predation appears to have been the best mode adopted by many animals to survive. The principle even applies to man, as some people display such behavior. When opportunities come, they strike with impunity, almost always successfully. Everywhere we see people taking advantage of others, acting like animals themselves. They may not be blamed for this because they acted on instinct. It is therefore a higher moral and spiritual virtue if we transcend this behavior and be more compassionate with our fellows. And rise above the level of animals.