Bifurcation is a universal pattern where one divides into two. It stems (pun intended) from the 'initial' appearance of division, where the singularity splits into two. We have a theory of The Big Bang, where the singularity exploded from one into many. We don't necessarily think of it as one splitting into two, but the splitting into two would be the start of the explosion, which then multiplied.
An obvious example of bifurcation is a tree. A tree has many branches where the trunk bifurcates and a branch goes out from the main one. This extra branch repeats the pattern and bifurcates, forming another branch, and so on. The pattern can also be seen in leaves where the midrib of a leaf bifurcates to form the veins of the leaf. Bifurcation is further evident in the evolution of the human body, where the limbs have 'branched' outwards from the main torso, and where fingers and toes have developed from the limbs.
The structure of veins in the human body also shows this pattern of bifurcation. Not only that, but each birth of a child demonstrates the pattern. From procreative union, where two people unite, an 'offshoot' develops. If we look at a family tree, we see the pattern of bifurcation, where a 'source' couple have a child that grows to adulthood, unites with another, then has another child, and so on, creating a complex branch of diversity.
Recognising this universal pattern, it should be no surprise that planets other than Earth should form creatures in the same manner. In other words, it should be no surprise that planets can develop creatures or life forms, and these life forms would follow the pattern of bifurcation. Humans have two arms and two legs because of the universal pattern of bifurcation. That doesn't mean that life forms from other planets will necessarily have the same, but there is a good chance that multiple legs and appendages develop. So, just because there are reports of 'alien' beings or Non-Human Intelligence that have two arms, two legs, fingers and toes, it doesn't mean that they must be related to human beings or necessarily from this planet. Rather, their life forms show the pattern of bifurcation and evolution throughout the apparent universe.
Bifurcation is the universal pattern of division and multiplication. One divides into two. Each of the two can then divide again, creating four, and so on. From this pattern the whole universe of diversity is created. Kind of.
Why kind of? Well, the division into two is a play of division and not a true division. The One Singularity from which the universe seems to have expanded and diversified remains complete. The One doesn't really become many different ones. It only seems to do that with the play of division. A tree doesn't really have many different branches. 'Branches' is an idea or term that helps us describe what we see in the tree. But the tree is simply the tree. We have given names to what seem to us to be parts of the tree, but they are not truly separate parts.
The tree is a small-scale example of the whole universe. The division of the universe is only conceptual. In reality the Singularity of the universe remains timelessly as it is.