There are certainties in life; the sky is blue, QPR are never going back to the Premiership, and there will always be more Zoo Tycoon.
Extinct Animals does what it says on the tin, bringing long-since dead animals back to life by manipulating fossils, and challenging you to shoe-horn in said fauna into your budding zoo.
The caveat is that these animals are not the easy to deal with - notably the angry dinosaurs which occasionally become enraged, turning your zoo to rubble and eating passers-by. Alright, not that last one.
The dinos need to be controlled by either your new ability to tranquillise them, or if it becomes a serious, your local dinosaur capture team. Players also have to deal with disease, hunting down the source of the illness by analysing food, objects and trees in the animals' enclosures.
This adds another level of depth to Zoo Tycoon 2, and it's a laugh playing House MD with your animals, even if it's easy.
Ultimately, Zoo Tycoon 2 has its audience, and this expansion builds upon the structure in place.
This isn't going to change the world, nor is it going to win any new gamers, but it's worth a go if you've got a copy of the game to hand, especially considering the bargain price of the Zoo Keeper Collection at the moment.
Grr. Argh. Etc