Forum:KB:Isomorphism

Is there an in-universe reason for why all species seem to have generally the same body structure (I'm talking about arms, legs, torso, head, all arranged the same way)? Perhaps a better way to say it is that they all seem to have similar physiologies.

I mean, what are the chances that so many alien races, each developing independently on different planets, happened to come to generally the same form? Even the faces of different aliens seem to share the same layout, with eyes, nose, mouth, etc.