Psychobiology students object to earthworm practical every year
Every year, a group of students enrolled in the bachelor’s program in psychobiology protest against the worm practical. They have ethical objections to dissecting earthworms.
Every academic year, a number of students* enrolled in the bachelor’s program in psychobiology have difficulty with the earthworm practical in year two. One of the requirements for passing the course is dissecting earthworms.
Some of these students have fundamental ethical objections to killing animals. They do not want to do this because of their religious beliefs or broader moral objections. Other students find dissection scary or disgusting and therefore do not want to do the worm practical.
The students also believe that the practical is outdated, because the biological processes in worms can now be simulated effectively using computer simulations. In their view, technological advances in simulation models are making the use of live animals in educational contexts increasingly unnecessary. They question why simulations, which are already used in the course, are not sufficient to achieve the same learning objectives.
Students dissect a earthworm and remove its nerve in order to study the potentials. “A potential is the basic building block of a signal in every living being. In order to properly understand these signals and make predictions about what happens to them in certain diseases, the nerve is manipulated and studied with the help of drugs,” Dawitz explains. Students simulate on the computer what a particular drug does to the nerve signal and test this in experiments with the nerves of earthworms. To ensure a good experiment, the nerves of several earthworms are tested.
Course coordinator Julia Dawitz and program director Erwin van Vliet confirm the annual complaints. In 2022, a group of 17 students joined forces to stop the dissection of earthworms and jointly raised the alarm with the course coordinator. Dawitz emphasizes that she talks to each of the students every year and that everyone ultimately completes the earthworm practical.
Earthworms are not covered by the Animal Experiments Act (Wet op de Dierproeven), because that only applies to vertebrates and squid. As a result, there are no legal restrictions or licensing requirements for the use of earthworms, and in theory, you could dissect an infinite number of worms in a study. The psychobiology program purchases the earthworms from a company that sells them as fishing bait.
Achieving learning outcomes
The worm practical is a necessary part of the psychobiology program. Dawitz refers to the learning outcomes of the Education and Examination Regulations (OER), which she must also adhere to as course coordinator. For example, students must learn to dissect in order to become good psychobiologists. That is why the practical cannot be replaced by a computer simulation alone.
In addition, psychobiology students must learn research skills specifically with biological material. “Biological data are variable by definition,” says Dawitz. This means that you do not always get the same result even though you are measuring the same thing. For example, every nerve in an earthworm could react slightly differently. “Learning to deal with that variation and then interpreting the data is something you can’t learn from a lecture or computer simulation alone. Students have to experience it for themselves. If a student reads in a scientific article that, for example, twenty nerves were tested, they need to know what makes working with biological material so difficult.”
Anesthetized in alcohol
Although the program is bound by the OER, attempts are still made to work with students within the framework of the final attainment levels. For example, students are encouraged to share nerves with each other so that fewer earthworms need to be killed.
The working method has also been adapted: whereas worms used to be placed on ice to paralyze them, they are now anesthetized in an alcohol solution. Dawitz: “It is also possible for a student who really doesn’t like it to dissect only one worm and have the rest dissected by their lab partner. That way, we always find a good solution.”
“At the same time, every year there are students who are incredibly inspired by the practical,” says Dawitz, “and enjoy it so much that they want to do more with the subject in their academic careers.”
*For this article, we spoke with a total of four students and alumni of psychobiology who had difficulty with the worm practical. None of them wanted to be named, for fear that it would have a negative impact on their careers.
