Tell verb – To give an oral or written account of in some detail. Discern is a synonym for tell in activity topic. Sometimes you can use "Discern" instead a verb "Tell", if it concerns topics such as same, ascertain. Nearby Words: telling, teller
It's very hard to tell what species some of them are meant to be without being told (Arloest is a panda; Farrago is a ferret; it's hard enough to tell them apart, let alone discern their respective species).