A divided State Board of Education - operating one member short Thursday - kept a requirement that Texas public school students be taught the "sufficiency or insufficiency" of common ancestry to explain gaps in the fossil record.
The board also voted for a new requirement that students study the "sufficiency and insufficiency" of natural selection to explain the complexity of cells.
Those were just two of several split votes on disputed aspects of the state science curriculum standards, which the 15-member board is currently rewriting.
Thursday's committee votes offered a prelude to the final votes expected today, but as board Chairman Don McLeroy, R-College Station, said, "Anything can happen."
The battle over the science curriculum standards in Texas has ignited a firestorm here and across the country, due in part to Texas' power, because of its size, to control what publishers put in textbooks.
Board members critical of evolution say they want students to study alternate theories of the origins of life. Critics of the challenges to teaching evolution say language encouraging alternate theories is a ploy by creationist board members to insert the discussion of religion in science class.
The board also adopted language that would have students study the "different views on the existence of global warming."
Board member Mary Helen Berlanga, who has voted against requiring students to learn the weaknesses of scientific theories, was not at Thursday's meeting because of a family emergency. The board meets again for a series of final votes today, and all members are expected to participate, Texas Education Agency spokeswoman Debbie Graves Ratcliffe said.
Given the history of the votes so far, the return of Berlanga, D-Corpus Christi, could have an impact on the rewrite today, but it may not be enough to keep the insufficiencies language out of the curriculum.
McLeroy pushed the language and is confident he has the votes he needs to keep it. McLeroy, who said he thinks that evolution taught uncritically undermines faith, has also said that he is not interested in trying to insert religion into science classrooms but just wants to be sure that students are encouraged to think critically about all scientific theories.
Ken Mercer, R-San Antonio, who represents Hays County and parts of Travis, introduced an amendment that would have kept current language in the curriculum requiring students be taught the "strengths and weaknesses" of science theories; it failed 7-7.