Take a little look to Evolution of Life on Earth

http://en.wikipedia.org/wiki/Stromatoporoidea
http://www.palaeos.com/Invertebrates/Porifera/Stromatoporoidea.html
http://www.mpm.edu/collections/learn/reef//stromatoporoids.html

The oldest Ordovician stromatoporoids from Australia

The Oldest Macroborers: Lower Cambrian of Labrador

http://www.sciencemag.org/cgi/content/abstract/197/4307/980-a

TOUR COURSE

"Evolution of Life on Earth"(3)

Chazy Reef at Isle LaMotte:
http://www.anr.state.vt.us/DEC/GEO/chazytxt.htm

Historical Geology
http://74.125.77.132/search?q=cache:OGjmzBxCoMUJ:www.geol.umd.edu/~tholtz/G102/102x2r08.pdf+oldest+stromatoporoids&hl=et&ct=clnk&cd=33


http://inlinethumb21.webshots.com/42068/2198606480100806216S500x500Q85.jpg