Check out this interactive timeline by the Discovery Channel online of some of the major extinctions that have occurred from the beginning of life on earth. It explains what is known about some of the major extinctions and shows what percentage of all species died off.
| 17 |
Microbe Finds Arsenic Tasty; Redefines Life
NASA scientists have discovered an amazing new life-form that redefines what we consider to be the basic building blocks of life. A microbe found at the bottom of Mono Lake in California seems able to live in a solution of arsenic which is poisonous to most other life. Phosphorus, which used to be considered one of the essential building blocks of life, is replaced by arsenic in this organism. Dr. Sasselov, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of an institute on the origins of life there said, “I would like to know, when designing experiments and instruments to look for life [on other planets], whether I should be looking for same stuff as here on Earth, or whether there are other options. Are we going to look for same molecules we love and know here, or broaden our search?” Seems like we have aliens right here on earth!!! |
| Dec 10 | |
