Large, Multicellular Creatures

In the writing, "Early life forms had a modular structure" found in (_Science News_ v. 166, 7/31/04, p. 78). "A cache of fossils recently unearthed in northeastern Newfoundland" includes "the oldest known examples of large, multicellular creatures and the first of their type to be found preserved as three-dimensional casts."

They are dated as pre-Cambrian at "about 565 million years ago." They reached sizes of 1 to 2 meters, and these particular fossils "preserved internal and external body features as small as 30 micrometers across." Scientists can see that their "main architectural element was a branching, frondlike structure...approximately 3 centimeters long and made up of branching tubes" from "a few millimeters in diameter" down to "less than 0.15 mm in diameter."

Yet with all this, "scientists debate whether they were animals, plants, or neither." Furthermore, "this type of creature--known as a rangeomorph--became extinct about 540 million years ago and doesn't appear to be related to any organisms that have lived since."

So not only do we have another case of the amazing diversity of life, we also have another major case of a life form that neither has transitional "ancestors" nor is in transition to anything else.

Until Next Time,
David Bump