One argument against scientific testing on animals is that physiological differences between humans and other species are too great. An animal’s response to a certain procedure or medication may tell us nothing about how a human will react.
Though we pride ourselves on looking different from rats, with their long tails and beady eyes, humans and rats are actually more alike than they are different. For starters, we’re both mammals and give birth to living young. We’re both warm blooded, and rats eat everything we do…and some things we don’t.
They even live where we live. Rats spreading disease have caused more deaths than all the wars we’ve ever fought. That’s because rats and humans have the same basic physiology, similar organs, and similar body plans, and therefore often suffer from the same diseases.
We both control our body chemistry using similar hormones, we both have nervous systems that work in the same way, and we both react similarly to infection and injury.
There’s absolutely no doubt that research on rats and other species has done a lot to advance modern medicine.
The ethical issues surrounding animal testing are still murky. But that certainly isn’t because animal testing tells us nothing about humans. It’s because it so often does.
Read more on what rats teach us about human behavior.