Eternally Individual

Because it is not possible to cut the soul, it is not possible to sever the individual soul from the Supersoul. Consequently the jiva, or individual soul, has always been individual because if it had ever been homogeneously one with the Supersoul, it would never have been possible to break it or cut it away. Therefore, Lord Krsna speaks of the jivas as "eternal fragments of Myself." "The living entities in this conditional world are My fragmental parts, and they are eternal. But due to conditioned life, they are struggling very hard with the six senses, which include the mind." (Bg. 15.7)

Because the soul can live under any material means, it can go anywhere and live anywhere. And we have practical experience that living entities are everywhere and that they acquire suitable bodies for their particular environments. If we dig deep into the earth, for instance, we will find so many worms, and of course on the earth's surface there are so many entities, and also in the air, and, of course, there are infinite creatures in the water.

And from Vedic sources we understand that even in fire there are many living entities that have particular bodies which are adaptable to living in fire, just as some souls can acquire bodies for living on a planet with no atmosphere. However, these bodies are more subtle and are difficult to perceive by the gross senses.