Killings by animals are the second largest cause of bird death in the United States.

VOA: special.2011.05.24

The history of the military in the United States and other countries includes a lot of attempts to get animals like pigeons or dolphins to do interesting and deadly things through various training.

各国在其军事史中,都有试图通过训练鸽子海豚等动物,去完成各种高难而致命任务的尝试。

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