A childhood belief about weeing and pooing

I first encountered the word "rectum" in connection with having a thermometer put in there. That convinced me that I had a special hole there, specifically dseigned for having my temperature measured. That was clear to me for quite some time while I still only vaguely realized that poopoo somehow happened in that same general vicinity, without being at all sure that it came out exactly where the thermometer went in. Later when I became clear exactly where my doodoo comes out, I learned the word "anus" in association with that. Realizing eventually that the same hole is involved with both, I thought the two words were function-specific: that it was my anus for purposes of pooping but my rectum for purposes of temperature measurement. Later when I learned of a creation vs. evolution controversy, part of the foucs I thought of when contempleting it was as a question of whether God made my rectum as a a special place just to put a thermometer, or whether my anus evolved as a hole where I could doodoo. Guess it was more comfortable at the time, when thinking of any creator God, to think of him as an enabler of temperature-taking rather than as an enabler of crap-taking.