With reference to: http://spectrum.ieee.org/automaton/robotics/robotics-software/042910-a-robot-that-balances-on-a-ball
It's hard to imagine a wheeled creature evolving. Scifi provides few examples, I believe David Brin touched on it (along with some very intriguing waxy-toroid creatures).
Let's imagine a Rolla bird. It is flightless but egg-laying, with thick fluffy feathers. The baby Rolla hatches in late Spring, as the first rays of sun strike its icy habitat and begin the thaw. It immediately lays an egg (unfertilised), half the size of the bird itself, and makes its first attempts at balance. As the thin snows clear, revealing the smooth glacier ice formed over polar volcano flows, movement becomes easier.
The Rolla sets out with its siblings in search of food. A pygymy spruce local to the area offers up pine nuts, just within reach of the infants. The pine nuts are difficult to digest for the small stomach of the baby bird and a substantial part is injected into the egg under its feet.
As the Rolla matures, this contribution is enhanced with additional enzymes and organisms. A nucleus forms within the mass of waste which becomes like a second stomach. The hardest parts, mostly bits of cone, are pumped outwards through a constantly extending network of cracks to expand and reinforce the egg. Softer parts which still carry nutrition are retained in the centre.
After a couple of months the Rolla has reached adulthood and migrates in search of a mate. Rollas are hermaphroditic and exchange ova while still upright. The foreign ova, injected into the egg, is fertilised by the DNA therein and begins to divide. The by-now thoroughly decayed soft food waste is consumed to fuel the growth.
No more than a month after conception, the adult Rolla bird lies down for the first and final time. Its frantic summer of feeding is over and winter stands in the wings like Death, beyond survival. As the days draw in, the adult dies and the egg is slowly buried in the snows. The thick outer shell and battery of nutrition will sustain it until the land is inhabitable once again, and this most independent of birds will hatch again.
I tried to introduce a couple of evolutionary triggers - a low-hanging food source and a killer winter not even a penguin could survive. The glacier ice is an attempt to explain WTF the place is flat enough for a wheel to work. It's still not the most probable of creatures but not entirely beyond imagination I hope!
The parent who dies before the child is born is rather compelling. Every year a new generation would be totally alone. It'd be interesting to extend this to a small planet, with an extremely long year and a civilizing race. Born in the snowy tropics, slowly migrating to the poles as the equator becomes uninhabitable then back again to breed and die. Each generation would discover the artefacts of the last as if a foreign people. The standard tradition vs discovery dichotomy would have to be reexamined when 'tradition' (IE following the example of prior generations) requires discovery. And of course there is a great, unavoidable extinction every generation.