Here is the full list of all 7 The Lonely Gorilla achievements.
Well done, you survived a full day!
Awesome, you survived a whole week in the wild!
Find all adults from your troop.
Find and eat all the different foods
Get close to all the different animals in the game.
You managed to mate with a troop member.
You found all your lost troop and mated with them all to produce a full troop of adults and infants.