Our soul is sexless. In one life we can be a woman, in the next we can be a man, and vice versa. In the interval when we died and are about to be reborn, a determination takes place whether we will be a man or a woman. In order for us to enter this Universe, we need a body.
We need to be provided with a body. Our dear mom and dad can do this. And what level, so to speak, what "quality" this body will be, depends on our karmic situation.
The kind of body we get is influenced by our spiritual level and the degree of our self-awareness. It is very important to get a body that will correspond to the amount of prana that we have. And this, in turn, is influenced by our spiritual level.
Everything is interconnected. Therefore, when we are born, we need a “shell” that corresponds to the level of our development. To be born “with a decline” is bad for our I. To be born with a decline means that in terms of the level of spiritual development we are worthy of the human body, but received the body of an animal. Yoga does not rule out such a scenario. It depends on how we lived our previous life.
Why is it bad not to get a human body?
Our higher self has accumulated a certain potential for many of its lives. This is expressed, first of all, in the degree to which I am aware of myself. The amount of prana we have at our disposal depends on this. And prana is the energy of life. Due to it, we have the opportunity to interact with the outside world and develop. Without this energy, there would be no way to manifest in this universe.
And if the level of prana has already reached the level of the human body, and as a result of our actions, we karmically receive the body of an animal, then in evolutionary terms we, at least, stop in development and have no opportunity to move to the next level.