A single whiff of formaldehyde transports many adults back to biology class and dissection. It's hard to forget the odor that arose from trays of rubbery, preserved frogs or fetal pigs.
But that rite of passage is now being challenged by students who find dissection objectionable on animal-rights grounds.
The issue came up recently on the prime-time television show "8 Simple Rules." The character Kerry, one of the two daughters, becomes concerned about frog dissection in her school and organizes a sit-in to protest the practice.
As animal-rights groups have stepped up their campaign to stop the use of animals for research, the message is being heeded by some students in middle and high school.
It's a controversy that pits animal rights against traditional methods of teaching science and anatomy.
"There's no substitute for dissection," says Wayne Carley, executive director of the National Association of Biology Teachers. He insists the move against dissection comes more from squeamish students being manipulated by radical animal-rights groups than from a groundswell of concern for animal welfare. "High school kids are easy targets," he says.
Still, the NABT supports the idea that "teachers should consider how their students would react [to dissection]," says Mr. Carley. "We support the wise use of animals, and that could mean a reduction in the number of specimen animals used."
About 6 million animals are dissected each year in US schools, according to the Humane Society of the United States. These include frogs, fetal pigs, and cats. The cats come from shelters that would have euthanized the animals, Carley says, or the animals are procured by dealers in the US or Mexico.
But today, the quest is on to find credible alternatives to dissection at all levels - from high school and college classrooms to research labs and veterinary schools. This means some type of computer simulation, such as can be found on websites such as www.froguts.com. Because the technology is still being refined, the programs for the most part aren't sophisticated. Some life-sciences teachers, including Jessica Crosby of Pollard Middle School in Needham, Mass., use virtual- dissection programs to prepare students for the real thing.
In April, before the unit on frog dissection, Ms. Crosby gave each of her 90 students a confidential survey that asked how hands-on they wanted to be during the procedure. This year, she says, although some were apprehensive at first, every student participated. "I saw how engaged the kids were. They were so proud that they could identify the organs," she says.
Nine states have laws or policies that allow students to opt out of dissection, according to the Humane Society of the United States, and several more are contemplating such measures.
But the issue goes deeper, says Andrew Rowan, chief of staff for animal research at the Humane Society. "It's much easier to get students' attention by dropping a dead animal in front of them," he says. "But when students are forced to do dissection, they're turned off. The lesson, which is in part to get them interested in science, has exactly the opposite effect."
Crosby says dissection offers an unmatched opportunity to see how each anatomical system is part of the whole. "I wouldn't force a student to do it if it violated their beliefs," she adds.
A March survey by the National Science Teachers Association showed that 80 percent of its members think dissection activities are important to science learning, with 76 percent including dissection of animal specimens in their lessons. Of the teachers who said they've decreased the frequency of dissection in class, the biggest reason cited was the expense of specimens, not pressure from students or outside groups.
Concern for animals in the larger society has trickled down to high school students, says Rowan. "As a society, we now think differently about hunting, about how well pets are treated, about cosmetics testing, and the rights of animals," he says. "But biology classes are still doing the same things they've always done. Biology should be a study of life, not death."
Crosby says her students seemed better able to recall the material after the dissection. "The virtual dissection is still on a screen," she says. "You're not really doing it."