Rune
Once A Fool
Pretty sure that change happened with 3e.If you are trying to shoehorn something into older editions, start with the kobolds who were more dog-folk until, what 4e days when the designers changed them. I do like the change into more dragon-folk, but I can keep the two separate like humans and halflings.
But anyway, along the lines of the OP, the older version of kobolds could evolve into gnolls, maybe?