October 26, 2001
More from National Geographic Did Plants Cool the Earth and Spark Explosion of Life? "Plants colonized Earth much earlier than previously believed, giving a jump start to the huge proliferation of animal species that occurred hundreds of million years ago, say scientists at Pennsylvania State University. Based on the fossil record, scientists have thought that land plants and fungi evolved around 480 million years ago. The researchers at Penn State propose much earlier dates based on molecular clock analysis: 700 million years ago for land plants, and 1.3 billion years ago for land fungi." Whoa...better change my lectures....
From National Geographic: Legged Sea Cow Fossil Found in Jamaica. "The nearly complete skeleton of an ancient aquatic mammal with legs has been unearthed in Jamaica.
The 50-million-year old skeleton is one of the best examples so far of the evolution from a land animal to an aquatic animal, said Daryl Domning, a paleontologist at Howard University in Washington, D.C., who reported the discovery.
The skeleton found in Seven Rivers, Jamaica, is a new genus and species of the order Sirenia, which encompasses the ancestors of modern-day manatees and dugongs."
October 17, 2001
From Scientific American: more info on the Snowball Earth.