Campaigners against the teaching of creationism in science lessons last week celebrated a key victory in Texas.
In meetings to revise science standards in Texan schools, the 15 members of the Texas State Board of Education elected to get rid of wording which has allowed the standing of evolution to be attacked for 20 years in Texan science lessons.
The offending wording invites teachers and students to debate "strengths and weaknesses" of scientific theories. In practice, this was used as a pretext to attack evolution in lessons and textbooks.
"Removing the concept of 'strengths and weaknesses', when the supposed weaknesses are completely bogus, is a real victory," says Michael Zimmerman of Butler University in Indianapolis, Indiana, and a campaigner against creationism.
"Its removal is a huge step forward," said Eugenie Scott, executive director of the National Center for Science Education in Oakland, California, and a witness at board meetings last week in Austin, Texas.
The clash in Texas is the latest between creationists, orchestrated by the pro-creationism Discovery Institute in Seattle, Washington, and mainstream scientists.
It follows a much larger test case in 2005 in the town of Dover, Pennsylvania, in which the Discovery Institute argued unsuccessfully for science lessons to include "intelligent design" - the idea that the universe is so complex that it must have been created by an unspecified designer. The trial exposed intelligent design to be creationism by another name.
The meetings last week were tense, as the elected board was finely split between creationists and scientists. Zimmerman says that six, including the chairman Don McLeroy, are creationists, and seven are definitely pro-science, leaving two "floaters" holding the balance of each vote.
In most cases, science had the edge eight to seven. But the creationists did manage to slip through some late amendments, mainly because of abstentions by members demanding more scientific advice on the matter before deciding.
The most serious amendment, one of five in the standards for teaching Earth in space and time, sought to throw doubt on the validity of the fossil record as solid evidence for evolution.
The previous text invited students to: "evaluate a variety of fossil types, transitional fossils, fossil lineages, and significant fossil deposits with regard to their appearance, completeness and rate and diversity of evolution".
The altered text, introduced by creationist member Barbara Cargill, slipped the phrase "proposed transitional fossils" into the text, implying unwarranted doubt about whether transitional fossils are genuinely evolutionary staging posts as species changed.
"Transitional fossils are not 'proposed'," says geologist Steven Schafersman, president of the campaign group Texas Citizens for Science. "There is no doubt about their existence, so insertion of the word 'proposed' makes that part unscientific, since it suggests a false uncertainty."
Secondly, Cargill scrapped the final clause altogether, replacing it with an invitation for students to "assess the arguments for and against universal common descent in the light of this fossil evidence".
In other words, she sought to stimulate unwarranted debate about common descent, the idea that all life arose through evolution.
"This change is by far the most unscientific revision, and is completely unacceptable," says Schafersman. "There are no good arguments in modern science 'against universal common descent', which has been accepted by biologists for over 130 years, so the phrase is asking for something that authors and publishers cannot honestly supply."
In essence, says Schafersman, "the added phrase supports an anti-evolution intent which is not scientific."
No more creationism?
The board is to agree the final text of the draft standard at a meeting on 26-27 March. The hope is that all the anti-evolution amendments can be removed then.
If they are, then Texas schoolbooks will be free of them for at least 10 years. But failure to remove them could lead to spread of the resultant pro-creationist standards to other states.
In the time between now and then, Zimmerman urges people to visit "Teach them Science", a site that he has helped set up through his "Clergy Project" initiative launched in 2006 to promote acceptance of evolution by churchgoers. The site was set up jointly with The Center for Inquiry, a secular group.