Yesterday I described an experiment I conducted with my late tomcat Teddy. When he trotted from the hallway of my apartment (where he greeted me in front of the elevator), into the apartment itself, his tail changed from the wary horizontal position to the happy vertical position. At what point during the transit from hallway to safehouse did Teddy’s tail go vertical?
I mentioned two hypotheses: when his head crossed the doorway (which would suggest that perception of the brain being inside was sufficient to induce happiness) or when his entire body had passed through the doorway, indicating that Teddy knew when his whole self was safe inside the apartment.
Most people voted for the latter, but a few suggested “head alone”
The answer: the tail went vertical only when Teddy’s whole body was inside.
I repeatedly observed that the moment Teddy’s butt (“bum” for you Brits) passed over the threshold of my place, his tail would rise up instantly.
Conclusion: Teddy became mentally secure only when he knew that his entire body was out of harm’s way, safe in my crib.
Now there’s a paper for Nature! (One would, of course, have to test many cats.)