@Setanta,
Now, now...you've not been listening at the back !
The observer-observed dichotomy refers to a polarity of co-extensive states interacting across an 'organism-environment ' boundary. Organisms have been defined as relatively stable dynamic 'dissipative structures' , simple examples of which have been shown to arise
spontaneosly in complex chemical situations.(Prigogine) Current writers on abiogenesis (Pross) tend to endorse this view, and one 'systems -theory' biologist (Maturana) haS even written that 'observation' always involves verbalization (what I call 'thinging') and is therefore a behavior which should only be ascribed to those organic systems sufficiently evolved to be engaged in 'languaging'.
From this pov, your pursuit of 'origin of observers' is facile since it ultimately boils down to a 'first cause' quest little different in substance from 'prime mover' theism. I thought you might have spotted that by now, but having got your teeth into attacking this 'fount of wisdom' your hormone system appears to be interfering with your rationality.
BTW 'Causality' has little status in modern physics in which the concept of 'time' has been deconstructed.