1save
ives?
30
goes to Sleep, the other half stays awaker' to helb ta
swWim, breathe, and be onthe lo0kout for danger.
Some migratoTy birds
way ofsleeping: they sleep up
in _the sky! For example,
Alpine swifts”have to keep flying for 章 time over
回
great distaneets duringtheir journey'"toand from Afriea
!
To eomplete'? this long trip, they eat insects in the air ant
take little naps While in fiight'?. This habit can save their
lives,as one step on the ground could allowa hungry ol
