英语听力：自然百科 虫虫兄弟—6（在线收听）

 Grain weevils are master safe crackers. Their battering ram shape snouts puncture most packaging. Like all insects, they don't have lungs but pump air through tiny pores on their outer skin. They don't like strong light, so layers of cereal couldn't be a better place to lay out the 450 eggs. This one is cut off in her prime. No harm done, just some extra protein. And the grain weevil colony has plenty of sisters to continue the family line. There's a even more free protein in the muesli, flour moth hide between the flakes, big enough to see with an naked eye, it's hard to eat one of these by mistake. While our human housemates take on extra vitamins without realizing, Holly provides breakfast for a family of fleas. The fleas flat armored body is designed to slip into the fur. These fleas have gone straight to work, siphoning off blood to extract 15 times their own body weight every day. Like all good engineers, fleas test the ground first, tapping around with a siphon like suckers to find the best place to drill. Relative to body size, their jaws are huge, designed to soar through skin and puncture a blood vessel. Then things get messy. Blood's sucked up using a pair of pumps in their head, and they are so desperate to feed, they spill fresh warm blood.