Origin and evolution of life
- Oct 23, 2002The first cellular organisms with a nucleus, called protists, now comprise nearly a quarter-million named species. Including green algae and parasites, they make up the first link in the complex food chain that not only sustains all life on Earth, but modifies terrestrial weather.
- Aug 12, 2002Do extinct species represent failed evolutionary experiments? At least for some more closely related to today's crabs and lobsters, University of Southern California scientist David Bottjer says that if many such early animals look strange to us, it is not because they were strange.
- Jul 31, 2002The most recent classification of all life on Earth includes three domains: Archaea, Bacteria (also called Eubacteria) and Eukarya, each of which contains a number of kingdoms.