Why not : le serpent mord sa queue ?
I guess because it's biting itself, you need to use a reflexive pronoun.
how do we know it is biting its own tail?
Because the reflexive "se mord" is used.
why not sa queue
With a reflexive verb, possessive adjectives are never used for body parts, because ownership is already implied.
Assuming we didn't know mord could be made reflexive, could "le serpent mord sa queue" also work as a translation?
Also: can virtually all verbs that can be turned upon oneself take reflexive pronouns?
What's the difference in French (from France) between serpent and couleuvre ? I always used the latter to mean any snake growing up. Serpent was more ... biblical
"Le serpent" is a generic noun : "les vipères (venimeuses) et les couleuvres (non venimeuses) sont des serpents".