Is dissection necessary to learn biology?
Many students feel that dissection is a “rite of passage” and look forward with eager anticipation to the physical dissection experience, not necessarily to learning anatomy and physiology. Others regard it with trepidation and hold religious, ethical or moral values that make the idea of dissection abhorrent.
Some teachers feel that students need to be exposed to the experience in order to “turn them on” to a career in medicine.
Firstly, let’s dispel the idea that middle and high school students need to master dissection skills; the only reason they are expected to dissect is to learn about anatomy and physiology — ultimately of their own bodies. Nancy Harrison, a practicing pathologist in San Diego, feels strongly that cutting up preserved flesh in school biology labs bears little resemblance to cutting up living tissue — and who would know better?
Dr. Kerry Kriger, founder of Save the Frogs, says, “I have never dissected a frog, yet I have excelled in a career in the biological sciences. As the founder and executive director of the world’s leading amphibian conservation, I feel it is safe to say that my failure to have dissected a frog in biology class has had little effect on my scientific or professional abilities. Thus, I do not see frog dissection as being integral to the success of any middle or high school student (and to only a few undergraduates). SUMMARY: Traditional frog dissection is by no means a prerequisite for a successful career in the biological sciences!”
Many believe that more students are “turned off’ by the experience than are “turned on.”
Are wet labs worth the time and expense?
Cost
Lab supplies for dissection classes are expensive and rarely re-usable. The total for 300 students can exceed $6800 over five years; this includes the cost of preserved specimens, other consumables such as gloves and scalpels as well as the disposal of biohazardous waste.
Time-intensive
It takes a lot of time to set up a wet lab and clean up afterwards. One study found that learning objectives could be met in approximately 44 percent less time using a computer program to learn anatomy and physiology. With teachers under more and more pressure to teach more in less time, wet labs may not provide adequate return on investment. Computer labs are maintained in schools for all subjects, so no additional set up time is required.
Effective learning?
In many cases, the “yuk factor” gets in the way of learning; adults tell us all the time that they remember the wet lab experience vividly, not the intended learning objectives. One of our beta testers told us he preferred dissecting real frogs because then he could “mash the brains into the desk”! Several studies have found that the computer learning was more effective than wet labs.
Difficult to make up missed classes
If students miss a wet lab, they usually have to study the textbook on their own. It is much more engaging and effective for a student to work on his/her own with an interactive computer program.
Classroom management
It can be challenging to manage a class of students wielding scalpels and biohazardous materials. The teacher cannot be everywhere at once. Students often do not know what they are seeing once they have made the cuts as their specimen may look nothing like the illustration in the text book.
Environmental issues
Impact on frog populations
Northern leopard frogs are one of the most common frogs used in wet labs and they do not breed well in captivity. This means that most of the frogs sold for dissection are caught in the wild, with a negative impact on the ecosystem.
Bullfrogs do breed well in captivity, but often have high rates of infectious diseases and when they escape into the wild outside of their native range they wreak havoc on native populations and other wildlife.
Use of chemicals
Formalin is the most widely used preservative for specimens. It is a suspected carcinogen, can harm the environment and poses a health risk to students through skin contact or inhalation of fumes. One teacher experienced a skin condition that erupted once a year — it was some time before she recognized that it was associated with the students’ annual rite of passage (cutting up preserved specimens).
Respect for life?
“Furthermore, teaching kids to cut up frogs does not teach them a respect for wildlife. Instead it teaches them that non-human animals are disposable and that they are here on this planet for our use. We should instead be focusing on teaching them that frogs have every bit as much right to exist on this planet as do we.”
— Dr. Kerry Kriger; October, 23 2010
Difficult concepts
Cell structure and function can be a very difficult concept to grasp as it is really hard to visualize such miniscule entities. Computer simulations help students gain an understanding of the complexities of such difficult topics. At the World Summit Awards judges commented that a computer simulation “entices the exploration of a complex structure of cells through stunning 3D models of the amazing range of organelles.”
What about digital field trips?
Few people would dispute that students benefit enormously from real field trips to a wide variety of places. Sadly, most teachers cannot take students on regular field trips; there is simply not enough time and money to do this. But, as educators, we do want to trigger a lifelong interest in the natural world.
Those fortunate few who can participate in such experiences will get much, much, more out of the experience if they study the ecosystem and know what to expect before they go. Digital field trips are an excellent way to do this.
For example, Digital Frog developers visited a rainforest in Belize, a bog in Ontario and several deserts in the southwest USA where they took thousands of photos and hundreds of videos. They stitched together hundreds of photos to create 360 degree panoramas that allow students to “experience” being there. They spent countless hours meticulously researching a wide range of topics, multiple curricular requirements and consulting experts. They then put together the information in engaging and interesting ways to accommodate a wide range of learning styles. They created a variety of “interactivities” to capture student interest. They added additional features such as definitions on every word, spoken pronunciations on significant words, a fast find utility, integrated text-to-speech and modifiable workbook materials.