Jakob Von Uexküll affirms that all the reality that an organism can perceive and with which it can interact, is the one that its sensory organs allow physiologically and its biological structure anatomically. In his studies of animals, he proposes that each organism is linked to a certain world (Welt) in which it lives, that is limited by its capacity to perceive. These limits would lead them to the description of their surrounding world (Umwelt), but only according to their "organs of perception" (Merkorgan) and their "organs of action" (Wirkorgan) characteristic of their phylogeny. A simple example that Uexküll uses is that of the night butterfly and the bat. The moth has only two antennae that allows it to perceive sounds above a certain threshold. One of these sounds is the screeching of the bat. The rest of the world is silent for the night butterfly. The bat, on the other hand, uses its screech as a flight orientation, allowing it to locate its prey or possible obstacles to its flight based on the sound echo. The meaning of this sound is very different for the Butterfly than for the bat. For her it is death, for him it is life. Each one giving it a meaning from its genetic peculiarity. How many meanings are there for you or me that are biologically determined? How many realities are there out there that we don't see because we don't have the right receptors? What is there that I don't see?