科學家檢測頭髮竟能判斷人的行蹤
A new laser can tell scientists what you ate for breakfast - just by looking at one of your hairs.
通過一種新的激光束，科學家看一下你的頭髮，就能知道你早餐吃了什麼。
The beam gives unprecedented sensitivity to chemical analysis and allows researchers to create an hour-by-hour picture of what an individual has eaten. They can even tell where a person has been by examining the chemicals which are in their hair.
這種激光束對化學物質極其敏感，通過它研究人員就能製出攝取食物的實時分析圖，甚至還能通過分析頭髮裏的物質，判斷出這個人的行蹤。
Previous techniques had burned hair samples but the new method breaks them down instead and allows far more precise readings.
以前的激光會把頭髮樣品燒燬，而這種新的激光會將頭髮分解掉，使研究人員能讀取更爲準確的數據。
The researchers hope that it could be used for forensic science or by biologists exploring ruins - in theory they will be able to find out far more about the diet of ancient fossils they find.
研究人員希望這種激光能幫助法醫或者生物學家，理論上講他們就能更加了解古生物的飲食結構了。
Lead researcher Jim Moran, a geochemist at Pacific Northwest National Laboratory, said: 'The carbon you eat goes into your hair, so hair is a record of carbon ratios. If you've been travelling, I could guess which countries you've been to or what you ate."
西北太平洋國家實驗室的首席研究員，地球化學家吉姆 莫蘭說：“你在食物中攝取的碳元素會儲存在你的頭髮裏，所以你的頭髮就記錄了食物中的碳含量。假如說你在旅行，通過你的頭髮我大概就能猜出你去過那個國家，吃過什麼東西。”
Currently the research is only looking at carbon in samples, but experts said that could soon expand beyond that.
目前的技術水平只能檢測出樣品中的碳含量，不過專家表示不久他們就能檢測出更多的化學物質。
Geochemist Alex Sessions of Caltech University, who wasn't involved in the research, told : 'Carbon tells you what you're eating, but nitrogen could tell you whether it's meat or plants. Oxygen isotopes vary with the water cycle, and sulfur with bedrock, so they're location proxies. Put them together, and you've got some really powerful data in space and time.'
加州科技大學的地球化學家埃裏克斯 賽申思並沒有參與這項研究，不過他在接受採訪時說：“通過碳元素研究人員能檢測出你吃了什麼，通過氮元素則能檢測出你吃的是肉還是蔬菜。氧同位素會隨着大氣水循環而變化，硫同位素則根據地球岩牀的不同而變化，通過它們我們就能確定地理位置。把所有這些數據放在一起，我們就能知道你在什麼時間去了哪些地方幹了什麼事情。”
