Since we have such different faces and body structures compared to dogs, how can they instinctively tell that the two spots on the upper portion of our faces are in fact our eyes, and not, for example, our nostrils?

When I eat certain cheeses (especially strong cheddar and old gouda), immediately after swallowing and before it reaches my stomach I get a strange sensation on my upper cheeks.

I feel a tingle and if i go for a second mouthful I get the sensation of sweating and very fine beads of sweat appear.

Why does it happen? Is it a tyramine response? Why is it so localised? - the location reminds me of a picture from an old anatomy textbook that described the position of the sensors on the face responsible for initiating the dive reflex.

Our smelling sensors are inside the head. Our noses are vulnerable to damage and the majority of primates and other mammals manage with relatively flat faces.

Dennis Newland, Purley, Surrey, UK

If skin cleansers are used to strip the grease and oils from our skin, does that leave the pores wide open, so that dirt (or other face creams) can get in and block them?

I have also read (on here) that our natural skin oils slows bacterial growth, so cleaning would let the bacteria breed more readily?

I can only raise my left eyebrow by itself to look quizzical. My right eyebrow won't work in the same way, although I can do both at once. Any ideas why this is? I'm right-handed, if that helps.

Polly Asquith, Paris, France