how comes penguins are birds and they have no wings ?

Question: how comes penguins are birds and they have no wings ?
- Keywords:
  bird,
  penguin,
  wings
Asked by datbagofswags to Becki, Rick on 28 Jun 2013.
- Rebecca Scott answered on 28 Jun 2013:
  
  That’s because the wings of the penguin have evolved over time into flippers to help them swim through the water.

Question: how comes penguins are birds and they have no wings ?