Joined: July 2005
If one accepts that the universe, solar system, earth itself, its atmosphere, biosphere, chemical makeup etc. preceeded life and I think there is common agreement on that premise; then what life forms could be created except those who had to successfully inhabit a world with an atmosphere and food source common to them all in large part and governed by the same physical laws of gravity, thermodynamics, chemistry, atomic theory etc.
Thus within limited variation a purposeful designer would by necessity and as a consequence of prior creative choices preceeding life have to have common design elements for respiration, energy conversion, metabolism, waste elimination, sensory perception, movement and motion in a gravitational field.
The only other boundaries on such a designer would be his own character and sovereign intentions, that would be sufficient.
Of course one can choose the ultimate in inefficiency, the most unintelligent approach to design ,, but that would be evolution by random mutation and natural selection.
Clearly no one serious about accomplishment in finite time and finite cost ever chose that method.. it simply could never create anything of any modest complexity... we can be sure of that by our use of mathmatical statistics and many have done so.