BRANCH 1 -Hexapoda

As it might be known by the reader, or not, the legendary creatures did not all came from magical experiments, but instead developed in a place where magical energy was stronger than it is in our dimension, and then ventured trough the shadow planes to colonize all the alternate realities, spreading trough all the multiverses.
What is certain though is that the branch we will be analizing now starded diverging from the normal animals at the number of legs stage. Here's the division:

As the name might suggest, the normal creatures (also referred as vulgar) present a common trait: the possess of four pous (greek for foot), while the mithycal ones have a MAXIMUM of six limbs (if there are mythical creatures that possesses more than six limbs, they will revolutionize this classification a bit going forward: some species now made as evolution of the initial hexapodalic ancestor might come from an octapodalic ancestor instead). 

Also as an important note I must say that not every mythical creature in the hexapoda branch has exactly six limbs; in a large variety of them one, two or more limbs atrophied during some stage of evolution, sometimes even the last stage

The two paths then seems to reunite, since the mithycal creatures took some steps down exactly mirroring the vulgar ones: even here we find the differentiation between amniota and amphibia (the latter having one or more larval stages, while the former making puppies either using eggs or giving birth like mammals). Some fantabilogist prefer to make a neat distinction between the vulgar and mythical creatures calling the two mythical series hexamniota and hexamphibia, but in this discussion of the subject we will not do that, since it actually doesn't make much sense: the distinction between amphibia and amniota is about the development of younglings , and not the number of limbs. Next time we will go a bit deeper into the amniota branch, skipping a couple of steps to reach the branch of the fearsome dragons.

Stay smart, my fellow students

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