参考リンク
http://www.youtube.com/watch?v=VTzfaY2kx0U 2:07 With prey plentiful, Spinosaurus can afford to be wasteful.
http://bridge-english.blogspot.jp/2012/07/blog-post_29.html 身銭を切ることの意味
http://bridge-english.blogspot.jp/2012/05/live-by-sword-die-by-sword.html live by the sword, die by the sword