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How Animal Testing Works

Experimental Experimenting
Though Charles Darwin was a supporter of animal testing, he supported humane methods.
Though Charles Darwin was a supporter of animal testing, he supported humane methods.
ullstein bild via Getty Images

For nearly as long as researchers have been using animals in scientific experiments, a debate has raged over the ethics of the practice. No less an authority than Charles Darwin himself waded into the controversy. Darwin believed passionately in the study of animal physiology, but he was equally driven to support the humane treatment of animals.

In 1874 four scientists were put on trial for torturing dogs during a demonstration in which the animals were cut open and infused with alcohol and absinthe to test the substances' effects on the nervous system, all without the benefit of anesthesia. The accused were acquitted, but the case was one of several that brought the issue of animal testing into the spotlight.

While some called for the outright ban of animal testing (or vivisection, as it was then called) Darwin began working with other, more moderate campaigners in the U.K. to craft a bill that would tightly regulate the practice. Believing that scientists could experiment with animals humanely, Darwin poured energy into what would become known as the Cruelty to Animals Act of 1876 [source: Johnson].

Regulation of animal testing has continued to be refined in the years since. In 1954 an organization called the Universities Federation of Animal Welfare decided to sponsor promising young zoologist/psychologist William Russell and Rex Burch, a microbiologist, in their efforts to look into the state of animal testing.

The report Russell and Burch produced in 1959 introduced a concept that has since become integral to the humane practice of animal testing. The concept is known as the 3Rs: replacement, reduction and refinement. The idea is that before conducting an experiment, researchers should seek to replace sentient creatures with non-sentient ones; where replacement is impossible, they should try to reduce the number of animals used to an absolute minimum; and finally scientists must refine their experimentation techniques to reduce the animals' suffering as much as possible [source: Flecknell]. The 3Rs are a simple way of articulating the regulations and requirements in the Animal Welfare Act. Researchers tend to adhere to these principles not only because they're humane, but also because they encourage better science.

If animal-rights advocates and pro-animal testing scientists can agree on one thing, it's the 3Rs. But organizations like PETA contend that much more should be done to replace, reduce and refine testing. They cite studies that demonstrate the superiority of alternative testing techniques. They say researchers should focus on using human volunteers, sophisticated computer modeling, and in-vitro human cells and tissues, which, they argue, have been shown to produce more accurate results than animal testing.

Those who support continued use of animals in testing argue that while alternative testing procedures are highly valuable, they haven't yet replaced every process. In certain cases, in-vitro testing and computer modeling can't be substituted for real bodies [source: Oxford University].

The debate rages on, and public opinion appears to be split on the issue of whether animals should be used for research [source: Pew]. Pressure from animal advocacy groups, together with the application of the 3Rs, has resulted in the steady decline in the use of certain animals for testing, particularly primates [source: Oxford University].

Those who feel that animals should be humanely treated, but simultaneously fear that banning animal testing could slow the pace of scientific advancement, are left with a quandary. Ultimately, to condone animal testing we must believe that human lives are more valuable than those of our non-human fellow earthlings. While such a belief is widely shared, it is a matter of bias, not fact. But we are biased creatures; there's no need to test the truth of that.