Since the world was created to entrap Humans, they also needed someone to guard it and be directly involved here to keep it functional. Thus, other "Reptilians" were also incarnated in "Human" bodies on Earth. The Human body would thus in turn take on characteristics from the Reptilian host, programmed into the cellular memory & DNA, and when Reptilians started to breed with Humans, new hybrids were born, that are a mix of Reptilians and Humans.

The Reptilians, in general, were put into places of Power in Mankinds society, while the Humans were put into places of Serving, or Slavery.

However, that DID change to some degree, because of Humans managing to take over certain areas, or infiltrate back in the Reptilians domains, and also thanks to the hybrid race, which offspring often assists the Human race towards rebellion against the pure Reptilian race.

Physically speaking, there is no difference between either of the 3 races - and in fact there are several other races involved on Earth as of this moment too, and other entities and beings have also influenced and controlled the Human race through all the time that has passed since the very first physical incarnations.

But, the physical Human body is always "Human" regardless of the "Controller" of the Body. The stories about Reptilian shapeshifters are based on misconceptions and people who do not understand what is really going on. There are no such things as "shapeshifters" in the physical sense of the word. ALL non-human entities that impose as "Humans" do so spiritually, meaning that they have a Human Body just like you and anyone else. The only difference is the inner self, the spirit inhabitating the body.

The reason there exist stories about "Shapeshifters" is simply because certain people have a more active spirit-vision or "astral sight", meaning they are "psychic" and can see the true form of such beings - and not knowing that what they really see is spiritual in nature, they misinterpret their experience as seeing a Human transform into a Reptilian, when in reality they saw the Human body, and the Reptilian inside it.