1) Airheads 2) Birds 1) An extinction of 2) Backward ones 3) Birds extinct by 1681 4) Birds extinct since 1681 5) Birds last seen in 1681 6) Birds no more 7) Blockheads 8) Bygone birds 9) Chuckleheads 10) Chumps 11) Clumsy extinct birds 12) Critters extinct since 1681 13) Defunct birds 14) Dim bulbs, so to speak 15) Dimwits 
dodos An extinction of dodos.