Based on the clue 'by the end of this era the last trilobite bit the ...', what is the answer?

Based on the clue 'by the end of the cold war the population of this ...', what is the answer? Based on the clue 'by the end of the middle ages this fermented honey...', what is the answer? Based on the clue 'by the end of the play prince henry then known as ...', what is the answer? What is associated with: by the end of the vietnam war the usaf was guiding bombs with this acronymic technology dating… Based on the clue 'by the end of this jm barrie play wendy flies so b...', what is the answer? Based on the clue 'by the end of this scottish play the title charact...', what is the answer? Based on the clue 'by the end of this sigmund romberg operetta the ti...', what is the answer? What is referred to by 'by the fact itself'?