Creatures of Ava

There are a total of 12 secondary quests that you'll need to complete. Note that like most other achievements in this game, if you leave an area too soon, you cannot go back later on. So, make sure to complete them as soon as possible (aside from two that carry over into each region).

Here is the list in the format of [QUEST_NAME - GIVEN_BY] in the order you will (likely) obtain and complete them:

Grasslands
Green Thumb - Ish'ar **
A Sculptor's Mastery - Fen'ti **
A Very Human Love - Ôbon
Human Hideaway - Vaeh'ti

Jungle
The Same River, Twice - Boh'ti
The Colors of Ava - Voor'lo

Grasslands (Post Jungle)
Staring Contest - Voor'lo
The Rhyming Scheme - Hon'lo

Swamp
Children of Ava - Kham'lo
Ava's Nostril - Epp'ar

Grasslands (Post Swamp)
Niiuiik, Come Home - Ûcup
Expressions of Love - Ôbon

** These quests will be the last ones you complete, as you need to collect plants and take a certain creature's photo, respectively, in each of the 4 areas. I would advise that once you get the necessary plants/photo, return to the Grasslands immediately, just so it's not forgotten.