The content you've requested is available without charge only to active Sigma Xi members and
If you are an active member or an individual subscriber, please log in now in order to access this article.
If you are not a member or individual subscriber, you can:
If you had been able to scuba dive during the Ordovician Period, some 450 million years ago, you would have seen at once that the seas swarmed with trilobites. These distant relatives of scorpions and spiders cruised the primeval oceans for nearly 270 million years before extinction finally took the life of the last trilobite about 250 million years ago. Despite their ancient departure, the trilobites left behind a rich fossil record in many parts of the world. Paleontologist Richard Fortey reconstructs the diverse habits practiced by the trilobites, which contributed to their evolutionary success.
Connect With Us:
An early peek at each new issue, with descriptions of feature articles, columns, and more. Issues contain links to everything in the latest issue's table of contents.News of book reviews published in American Scientist and around the web, as well as other noteworthy happenings in the world of science books.
To sign up for automatic emails of the American Scientist Update and Scientists' Nightstand issues, create an online profile, then sign up in the My AmSci area.
JSTOR, the online academic archive, contains complete back issues of American Scientist from 1913 (known then as the Sigma Xi Quarterly) through 2005.
The table of contents for each issue is freely available to all users; those with institutional access can read each complete issue.
View the full collection here.
Receive notification when new content is posted from the entire website, or choose from the customized feeds available.