The hummingbird, with miniature wings flapping furiously so as to hover in place, makes its way south every winter.
It's a migration shared by Angry Birds Rio, which also seems to hover rather than fly forward.
Cleverly tied to Fox animated film Rio, set in colourful Brazil, this highly anticipated physics puzzler entertains despite the lack of new elements needed to make it distinct from earlier instalments of the Angry Birds franchise.
Birds of a feather slingshot together
Although the pernicious pigs have been axed, the goal in Angry Birds Rio remains to slingshot the foul-tempered fliers across levels packed with objects. Concrete blocks, wooden crates, bird cages, metal chains, and even foliage are meant to be busted and broken with a slide of a finger.
Your objective is to free birds cruelly caged in the ominous Smugglers' Den, whereas marmosets are the target in the final set of levels set in the jungle. In total, the game packs a satisfying 60 levels with the generous promise of more coming throughout the year in four (presumably free) updates.
It's solid value on iPhone and iPod touch - less so on iPad where the tripled price tag comes without any added value - yet Angry Birds Rio feels more like a level pack than standalone game. While enjoyable, there's not much new or particularly thrilling here.
Creatures of habit
There's a surprising lack of creativity reflected in the absence of any new gameplay features or mechanics. This is essentially the same game as the original Angry Birds with pigs swapped out for caged birds and tree-climbing mammals.
Oddly, there are no new birds to throw and few new objects to break. Given the new setting, the opportunity to introduce new elements has been completely squandered. Why not debut a toucan that can roll through objects with its massive beak after it hits the ground? How about a parrot capable of cracking past concrete blocks?
More creativity has been applied with regards to the objects, which include new hanging chains and tropical tree branches. Still, it feels as though developer Rovio Mobile is playing it safe by repeating the Angry Birds formula rather than evolving it. That isn't to say it isn't fun - it's just not as fresh.
To be fair, there is a token effort to introduce new ideas. The final level features the film's main characters in a climatic boss battle. It's a neat level and I wish this sort of creativity had been applied throughout the game.
Angry Birds Rio does exhibit a degree of polish missing from earlier instalments. Levels don't feel quite so random, level layouts are tighter and more interesting. New in-game awards and hidden fruit add replay value beyond the quest for three-star ratings and unlocking every last Game Center achievement.
These provide a slight edge over the last game, Angry Birds Seasons, though not enough to fling it to the front of the franchise. In other words, Angry Birds Rio offers predictably solid physics puzzle play that hovers in place rather than flies forward.