你，一小时释放100万个粒子｜科学60秒
养宠物的人可能会烦恼房子里满是猫猫狗狗的毛，但其实我们人类也好不到哪去，我们掉下的东西甚至还是活着的。“我们不断向周围环境释放着微生物，它们来自我们脱落的皮肤、呼出的气体还有我们的头发，我们身上满是这些东西。”俄勒冈大学（University of Oregon）的微生物生态学家亚当·阿尔特里克特（Adam Altrichter）说道，“人类从来都不是无菌生物，我们体内和体表肯定都存在着大量微生物。”
如果你想到了《花生漫画》（Peanuts，注：著名的查理·布朗和史努比的故事）中的角色乒乓（Pig Pen），你可能离真相不远了，生物学家估计，我们每小时会排放出100万个粒子，当然，这其中包括很多细菌。阿尔特里克特和同事想对这种粒子云进行测量，也就是所谓的“乒乓”效应，他们找来11名受试者，让这些人不要洗澡，然后穿上短裤和背心在无菌室里一起待上几个小时，同时收集无菌室表面和空气中的微生物样本。
在这些样本中，他们发现了来自受试者皮肤、内脏、生殖道、肺、鼻子……[查看全文]
We Emit Clouds of Microbes Wherever We Go
You might blame your pets for shedding all over the house. But we humans do it too—and our stuff is alive. 'We're constantly emitting microbes around us. And this is coming from shedding of our skin, from exhaling, our hair, we're just full of these guys.' Adam Altrichter, a microbial ecologist at the University of Oregon. 'We've never been sterile organisms. We are definitely masses of microbes both in and on us.'
If you're picturing the Peanuts character Pig Pen, you may not be far off. Because biologists estimate we shed a million particles an hour—including, of course, a lot of bacteria. Altrichter and his colleagues wanted to measure that cloud of particles—the 'Pig Pen' effect, if you will—so they asked 11 volunteers not to shower, dressed them in shorts and tank tops, and put them in a sterile chamber for hours at a time, while collecting microbial samples on surfaces and in the air.
What they found in those samples was a menagerie of bacteria from the volunteers' skin, guts, genital tracts, lungs, noses...[full transcript]