Taylor also is leading a hike from 2 to 4 p.m. Saturday at Morgan Territory Regional Preserve east of Mount Diablo. The theme is "poopology," that is to say the group will hunt for scat, tracks, game trails and other signs of the preserve's abundant wildlife.

For five zookeepers from Hogtown, yesterday was to have been spent learning about everything from giraffe management to "poopology" at the opening day of the annual conference for the American Association of Zookeepers in New Orleans.

The 7.1-kilogram rock has been identified as the mineralized fecal remains left behind when a tyrannosaurus…relieved itself in a river delta 65 million years ago….'It is the birth of the science of [comparative] poopology,' Stanford University paleontologist and co-author Gregory Erickson said of the find's significance.