The aim of Philadelphia's citywide event is to increase understanding of evolution and science, at a time when polls show most Americans believe God created man as he is.
In the long-running culture war between evolution and creationism, Philadelphia is firing the latest shot.
Nine academic, scientific and cultural institutions around the city are holding a Year of Evolution, a series of exhibitions, seminars and lectures to celebrate the 200th anniversary of the birth of Charles Darwin in February, and the 150th anniversary of the publication of his seminal work, "The Origin of Species."
Events will include a talk by John E. Jones III, a federal judge who ruled in 2005 that teaching intelligent design -- the belief that some aspects of nature are so complex that they must be the work of a higher power rather than of evolution -- in public school science classes was unconstitutional.
The intent of the event, said Janet Monge, one of the organizers, is to increase public understanding of evolution and science in general at a time when polls show that a majority of Americans believe God created man in his present form and that the number of people who accept the evolutionary model of human origins is declining.
"The strengths and weaknesses of evolution are the strengths and weaknesses of science," said Monge, the curator of the Museum of Archaeology and Anthropology at the University of Pennsylvania. "You don't get answers."
She said the Philadelphia events were also intended to encourage people to consider the evolutionary alternative to the biblical account of the origins of man, as represented by the new Creation Museum in Petersburg, Ky., a $35 million institution that has attracted more than 400,000 visitors since it opened in May 2007.
Ken Ham, president of the Creation Museum, said he expected to see more pro-evolution events as the Darwin anniversary approaches. Ham said that in response his museum was planning its own exhibits on the origins of life.
"The culture war is definitely heating up," he said.
Ham, who also leads Answers in Genesis, a nonprofit group promoting a literal interpretation of the biblical creation story, defined the clash of ideas as "Christianity versus the relative morality of secular humanism" and said they were "two fundamentally different world views."
He rejected the possibility that Christians could believe in evolution. "If you take Genesis as literal history, then of course the two are exclusive," he said. "Christians who believe in evolution are being inconsistent."
Creationists and their allies in the intelligent design movement suffered a setback when Jones rejected a plan by the school board in Dover, Pa., to teach their ideas. Jones sided with the American Civil Liberties Union and others who sued the school board, arguing that intelligent design was a religious rather than scientific concept and had no place in science classes.
The National Council for Science Education, which opposes creationism in schools, contends that creationists and intelligent design proponents have merely changed their tactics to avoid legal challenges in the wake of the Dover decision, and are now arguing that teachers should have a right to teach critiques of evolution.
"The creationists are resilient, and they have regrouped," said Glenn Branch, deputy director of the council.
The council, which monitors creationist activity, said there had been 33 new cases of anti-evolution initiatives in schools or state legislatures this year, compared with 49 in 2007.
In Philadelphia, organizers of the Year of Evolution want to promote the concept in Darwin's anniversary year but have no interest in picking a fight with Christians who do not accept it, said William Y. Brown, president of the Academy of Natural Sciences, a participating institution.
"We will try to find ways of persuading people that it's not in conflict with their faith," Brown said.