Here are the animals I would love to see added to the game (excluding birds/exhibits).
Arctic
Arctic fox
puffin
walrus
muskox
wolverine
sea otter
South America
capybara
sloth
emperor tamarin
golden lion tamarin
giant Armadillo
howler monkey
ocelot
South American river turtle
Africa
meerkat
black/white rhino
fennec fox
African leopard
African penguin
red river hog
Australia
Tasmanian Devil
platypus
echidna
wombat
emu
Asia
markhor
caracal
Przewalski's wild horse
Southeast Asia
sun bear
Asian small clawed otter
binturong
gibbon
North America
American alligator
beaver
cougar
moose
Arctic
Arctic fox
puffin
walrus
muskox
wolverine
sea otter
South America
capybara
sloth
emperor tamarin
golden lion tamarin
giant Armadillo
howler monkey
ocelot
South American river turtle
Africa
meerkat
black/white rhino
fennec fox
African leopard
African penguin
red river hog
Australia
Tasmanian Devil
platypus
echidna
wombat
emu
Asia
markhor
caracal
Przewalski's wild horse
Southeast Asia
sun bear
Asian small clawed otter
binturong
gibbon
North America
American alligator
beaver
cougar
moose