- 积分
- 17983
- 威望
- 17983
- 包包
- 26159
|
8 V% [% ~! Z7 e# ~! v6 a
) T" I# V2 [1 M! p- kOVER Orbulina universa, a planktonic foraminifera captured live from surface waters off Santa Catalina Island, California. Symbiotic dinoflagellates inhabit the calcite spines (length ~2.5 millimeters) radiating out from a spherical calcite shell (diameter ~0.5 millimeters). After four weeks, the shells sink to the sea floor and become part of the deep-sea microfossil assemblage. The geochemical compositions of these fossils are used to reconstruct past changes in seawater chemistry (see page 818). Photo: Howard J. Spero, University of California, Davis
" @0 t0 g" r/ Z. K* S5 p: o/ m @7 E6 P* A2 b) Y5 \- k
[hide][/hide] |
附件: 你需要登录才可以下载或查看附件。没有帐号?注册
-
总评分: 威望 + 40
包包 + 40
查看全部评分
|