The concept of what determines our life form in the next birth varies across different belief systems and religious or philosophical traditions. Here are a few perspectives:
Reincarnation and Karma: In some belief systems, such as certain forms of Hinduism and Buddhism, it is believed that our actions in this life, known as karma, influence our future life form. The nature of our thoughts, words, and deeds in the present life is said to shape our destiny in the next life. The specific circumstances, species, or life form we are reborn into are seen as a reflection of the accumulated karma from past lives.
Divine Will: Some religious traditions suggest that the decision of our life form in the next birth is determined by a higher power or divine will. The belief is that this higher power, based on its own wisdom and purposes, determines the conditions and circumstances into which we are born.
Randomness or Chance: From a more secular or non-spiritual perspective, some individuals may believe that the next life form is determined by random chance or natural processes. They may perceive life as a result of natural selection, genetic variations, environmental factors, or a combination of these elements without invoking any supernatural or metaphysical explanation.
It's important to note that the concept of rebirth, and the factors influencing it, is a matter of personal belief, faith, and philosophical interpretation. Different cultures and religions have diverse beliefs regarding the nature of existence, the soul, and the process of reincarnation or rebirth.