Which flightless bird is described as sending a dingo running for cover with one swipe of her razor-sharp toe claws?

Where do most flightless birds evolve flightlessness according to the transcript?

What is a common reason for the extinction of flightless birds according to the transcript?

Which flightless bird species has been flightless for tens of millions of years?

What do penguins repurpose their flight muscles and keels for?

What change happens to flightless birds' bones according to the transcript?