国产18禁黄网站免费观看,99爱在线精品免费观看,粉嫩metart人体欣赏,99久久99精品久久久久久,6080亚洲人久久精品

20101017иԇxC(jng)ؑ

rg2010-10-19 10:02:00   ԴonW(wng)     [wС ]
1017иԇ˚gϲ˱¾1017иԇC(jng)ϣ܎



1017иԇxC(jng)



һƪprehistoric diet



P1,many ways to know the prehistoric diet, one way--indirect---ͨ^rnatural environmentr(nng)I(y)Դ֪ʲô(})however,the flaw of this method---can't know what's the most important part of their diet(})



P2,another way--direct--ͨ^food remains in the garbage heaps or other sites---problem: the food remains usuallly fragile(~R})--a solution by scientists: һBһȡ،ңһNliquidʹ֮xfood remainsorganic@Nliquid渡(Ӻ})



P3,ͨ^Xwear on the teethõgeneral info about their diet, for example, dog teeth---meat(})



ڶƪmorphography



P1 same species of plant,different in different light conditions



P2, two examples can only live well in specific light environment while others can adapt to various light conditions



P3, £moss LLstem--@elongationڏ£Ldiameter



P4ԞIJ@Nr~Ҳչʾelongationand they can compete for light



ƪ



p1ǰһֱԞןo19th century l(f)F(xin)һȻlead to many researches



p2ǰһֱԞﶼСsnailswormsǺl(f)F(xin)䌍ǺҰUreason: lack of competition, abundance in food and lack of juvenile(}@~ҪJR)



p3,antarctic l(f)F(xin)ȻϰٷN~



P4AntarcticaһNbarrierKˮ~ȥwarm~MȻůҲM@Щ~һNspecial blood protein which bind to the crystal so that they can survive



P5,׵bacteriaorganismǧpressure,ŵС300pressureĕr