While we were in Temburong, Donald was supervising his student there, and he told me that there is no scientific distinction between butterflies and moths, just like the lack of distinction between frogs and toads that I discussed earlier (see Frogs and Toads).
Now, in popular usage, we tend to think of them as different, of course. Butterflies are diurnal and they tend to be brightly coloured. In contrast, moths are mostly nocturnal, and because they use scent to find their mates, their antennae tend to be larger. However, there is no scientific basis for this distinction, and they are both classified as Lepidoptera.
This is one more instance where popular language usage deviates from scientific taxonomy.
