All souls are equal.
Within the body of all living beings (animals, plants and humans) there is a soul. All souls are eternal, full of bliss, full of knowledge, and equal.
“I hate no one. I am equal to all living beings…” (Lord Krishna, Bhagavad-Gita 9.29)
Lord Krishna is equal to everyone (in quality NOT quantity). This is another uniqueness of the Vedic teachings which cannot be found in the non-Vedic teachings where the animals are considered as food for humans, and those who don’t follow their ideology are considered low and sent to hell eternally.
There are 8.4 million species of living beings, and depending on the desires and mentality developed by souls in human bodies, the variety of people, plants, and animals are created.
“Just as the air carries a particular smell from one place to another, the living entity will be carried to a particular body at death, based on the consciousness developed by him during life. On taking a new body, the living entity will get a particular set of senses, like ears, eyes, tongue, smelling potency, sense of touch, and mentality. The foolish persons cannot understand how a living entity quits one body to take another. But those with knowledge can see this.” (Lord Krishna, Bhagavad-Gita 15.8-10)
“Whatever nature, one has at the time of death. That nature he will attain without a doubt.” (Lord Krishna, Bhagavad-Gita 8.6)
If we live a life full of sin then our consciousness at death will be polluted and the result is degradation to lower species. If we live a pious life and engage in devotional service unto Lord Krishna, then at death, our soul will be immediately transferred to the spiritual creation, Vaikuntha. Where everyone lives eternally in the same body that is completely beautiful, full of bliss/love, full of knowledge, with no old age, no disease, and without any misery.