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Rose
06-28-2012, 08:43 PM
Tiny Tracks of First Complex Animal Life Discovered

Jeanna Bryner, LiveScience Managing Editor

A teensy sluglike animal that wriggled around the sediment in search of food at least 585 million years ago didn't die in vain. The tiny mover left behind tracks that researchers now say represent evidence of the earliest known bilateral animal, or multicellular life with bilateral symmetry.

The finding, detailed in the June 29 issue of the journal Science, pushes back the date for the existence of advanced multicellular animal life (http://www.livescience.com/14390-deepest-worms-discovered.html) by at least 30 million years. The oldest evidence before this discovery came from Russia and dated to 555 million years ago.

Geologists Ernesto Pecoits and Natalie Aubet of the University of Alberta in Canada were studying the rocks at a site in Uruguay in 2007 when they discovered the tracks. They saw that the tracks had been made by a bilaterian, or an animal with bilateral symmetry (http://www.livescience.com/20196-brittle-star-movement.html), with a front and back as well as a top and bottom, unlike corals and sponges. (Tiny sea sponges (http://www.livescience.com/3267-oldest-fossil-evidence-animals.html) date back at least 635 million years.)

"But at that point we didn't realize the importance of this discovery, because we didn't know the age of these rocks," Pecoits told LiveScience.
The animal would have been about 0.2 to 0.3 inches (4-7 millimeters) long and 0.04 to 0.08 inches (1-2 mm) wide. Tiny features of the tracks, which were about 0.8 inches (2 centimeters) long, suggest the soft-bodied creature used its musculature and leglike appendages to move along the sediment just below a thin layer of organic matter. The animal was so primitive that it could move only parallel to the sediment and not downward, Pecoits said. Read more here...http://www.livescience.com/21256-tiny-tracks-earliest-multicellular-animal.html

Richard Amiel McGough
06-28-2012, 08:48 PM
Tiny Tracks of First Complex Animal Life Discovered

Jeanna Bryner, LiveScience Managing Editor

A teensy sluglike animal that wriggled around the sediment in search of food at least 585 million years ago didn't die in vain. The tiny mover left behind tracks that researchers now say represent evidence of the earliest known bilateral animal, or multicellular life with bilateral symmetry.

The finding, detailed in the June 29 issue of the journal Science, pushes back the date for the existence of advanced multicellular animal life (http://www.livescience.com/14390-deepest-worms-discovered.html) by at least 30 million years. The oldest evidence before this discovery came from Russia and dated to 555 million years ago.

Geologists Ernesto Pecoits and Natalie Aubet of the University of Alberta in Canada were studying the rocks at a site in Uruguay in 2007 when they discovered the tracks. They saw that the tracks had been made by a bilaterian, or an animal with bilateral symmetry (http://www.livescience.com/20196-brittle-star-movement.html), with a front and back as well as a top and bottom, unlike corals and sponges. (Tiny sea sponges (http://www.livescience.com/3267-oldest-fossil-evidence-animals.html) date back at least 635 million years.)

"But at that point we didn't realize the importance of this discovery, because we didn't know the age of these rocks," Pecoits told LiveScience.
The animal would have been about 0.2 to 0.3 inches (4-7 millimeters) long and 0.04 to 0.08 inches (1-2 mm) wide. Tiny features of the tracks, which were about 0.8 inches (2 centimeters) long, suggest the soft-bodied creature used its musculature and leglike appendages to move along the sediment just below a thin layer of organic matter. The animal was so primitive that it could move only parallel to the sediment and not downward, Pecoits said. Read more here...http://www.livescience.com/21256-tiny-tracks-earliest-multicellular-animal.html









Very cool! Thanks baby, :flowers:

One of the stronger evidences for evolution is that the complexity of the fossilized organisms decreases as the rocks get older. I find that very convincing.