MitD XIII: Learning is happening

[monomer]

In regards to size vs age, for snakes in particular, the only decent resource I've found is this chart on a Ball (or Royal) Python forum. It basically shows the ball python at roughly 180 grams at 4 months of age, growing up to 1800 grams by about 35 months, or a 10x growth from childhood to elderly.

According to Wikipedia, in the wild, male royal pythons reach sexual maturity at 11-18 months, but don't generally start breeding until at about 600g, which according to the above referenced chart is at roughly 11-months old. It also notes that in captivity some Ball Pythons have begun breeding at 300-400g, which is about 8-10 moths of age.

Now, making a bunch of wild assumptions, it seems like they reach puberty at around 8, and adulthood around 11. If we consider the MitD as pre-pubescent, though not a newborn or young child (let's say equivalent to a 6-month old, ~200g ball python), then a 10x change in size isn't out of the realms of possibility. So that accounts for one whole size class, if it were to follow an Earth snake-like growth. Extrapolating that to D&D doesn't really work that great, since monsters can live for thousands of years, and if they never stop growing, similar to snakes or dragons, then they could conceivably reach larger and larger size classes.

For the Ha-Naga, The Epic Handbook fluff is not really indicative of how old they are, or even what their reproductive cycle is like. Serpent Kingdoms, however, notes (page 25) that Ha-Nagas came about from some Dark and Spirit Nagas seeking out ancient Sarrukh rituals and transforming themselves into Ha-Nagas.

Another interesting note from Serpent Kingdoms (page 26) says that Nagas are hermaphroditic and are capable of reproduction through either self-fertilization or copulation with another Naga, depending on the individual's preference. The young are raised by their parent until they are strong enough to survive on their own, at which point the parent leaves for good.