"oriel36" wrote in message
...
An 'untilted' Earth is the same as an Earth with zero inclination in
which case the Earth's climate would be equatorial insofar as there
would be little or no change in conditions.

What would remain the same regardless of inclination are the
variations in the natural noon cycles arising from the orbital
component of the Earth's motion working in tandem with daily
rotation,in this case,the equation of time as it refers the 1461
natural noon cycles to the 1461 twenty four hour AM/PM cycles would
remain the same.

No, that's wrong.
The equation of time has TWO components.
One comes from the elliptical orbit of the Earth and and hence its varying speed
around the Sun.
The other comes from the inclination in the Earth's orbital plane, which results in a
non-uniform increase in R.A over the course of a year.

On an Earth with 'zero inclination', the second factor would be absent, so the
equation of time would not remain the same.

http://en.wikipedia.org/wiki/Equation_of_time