Number of Dissections for Biology

[momtotkbb]

I'm curious after talking to some other hs mom's and to kids in our local high school Bio classes -- how many dissections do you consider necessary for General Biology?

[regentrude]

None. I believe one can design a rigorous lab that does not include dissections, but focuses on other aspects of biology.

[TheHomeScientist]

None. I believe one can design a rigorous lab that does not include dissections, but focuses on other aspects of biology.

 

I agree.

 

Dissections not only aren't necessary for a first-year biology lab course, but they take up a lot of time, effort, and money that could be much better used otherwise.

 

Then there's the yuckiness factor. I'm convinced that dissections have turned off more kids to biology in particular and science in general than any other issue. And, of course, some people have ethical objections.

[Jane in NC]

When the focus of biology was taxonomy and systematics, dissection was used for reinforcement.

 

A modern biology class focuses on biochemistry, the cell, evolutionary motivation, animal behavior, etc. Dissection is not necessary but can be illuminating for some students.

 

Whether you include dissections really depends upon the nature of the class.

[MidwesternMom]

None for us. We had a big ruckus at homeschool co-op about them; many kids objected on animal cruelty grounds vs. a few parents who said their kids "needed" dissections to "get into vet school."

 

Yes. I quote.

 

Our vet, when surveyed, said they are unecessary not only in high school but in undergrad as well, and there are video dissections that work well for everything up until the point where you need the real deal.

 

That was all it took for me. No dissections.

[TheHomeScientist]

When the focus of biology was taxonomy and systematics, dissection was used for reinforcement.

 

A modern biology class focuses on biochemistry, the cell, evolutionary motivation, animal behavior, etc. Dissection is not necessary but can be illuminating for some students.

 

Whether you include dissections really depends upon the nature of the class.

 

Exactly. For a typical first-year biology course, dissections should be a very low priority. There's too much other stuff to get done.

 

I'd reserve dissections for a second- or third-year course in (really) gross anatomy.

[EKS]

Zero. Dissections are not part of a modern biology course.

[TheHomeScientist]

None for us. We had a big ruckus at homeschool co-op about them; many kids objected on animal cruelty grounds vs. a few parents who said their kids "needed" dissections to "get into vet school."

 

Yes. I quote.

 

Our vet, when surveyed, said they are unecessary not only in high school but in undergrad as well, and there are video dissections that work well for everything up until the point where you need the real deal.

 

That was all it took for me. No dissections.

 

I was stunned a few months ago when our vet, who is also a friend of 30 years' standing, told us that many vet schools no longer have students operate on animals. The first time a vet does surgery on a living animal, it may be someone's pet.

[BakersDozen]

Dissections have been a highlight for our Biology study this year so for me the more the better! We've dissected a starfish, earthworm, frog, crayfish, fish and grasshopper so far. I must say that anatomy has been very much reinforced via dissection and I do not feel we have wasted any time doing the dissections we have.

 

Dissections have also showed me that my 7yod is probably going to be a pathologist. :D

[SuperDad]

Zero. Dissections are not part of a modern biology course.

 

:iagree: I also agree with pretty much every word TheHomeScientist has ever posted. :D

[mumto2]

My DD is really looking forward to it. My DS is dreading it. We have a compromise we plan to dissect things for the most part that we can eat. I admit we live in the UK which mean that my butcher and fishmonger will help. But I do think you can find sources in the US with some effort. Anyway we plan to get a very fresh fish, dissect it, then clean and cook it. That way the fish will not have died in vain. The dissection will be harder though without the Colour coding.

 

I have no idea how many we will do. I guess until they run out of ideas.

[momtotkbb]

This has been enlightening. I had taken the stance w/ a couple moms that I felt that labs and in particular dissections were an integral part of bio. I felt that if a student wanted to go into a science field but were hesitant to do dissections it was better to get it under their belt in high school at home than when they went to college and took Bio 101 and had to complete their first dissection. I didn't realize until I began searching the internet today that dissections were not completed in all high school bio courses and that many schools were doing only virtual dissections. We are required by our accountability assoc to show a certain number of labs and dissections are to be part of that - more are needed for an honors v a gen bio of course. I was basing my decisions on my past schooling, my oldest ds's completion of honors and AP bio in ps and my accountability assoc.

 

We completed two dissections for dd in 7th Life science - a frog and earthworm. For her honors bio this year we are doing a frog again, perch, fetal pig, cows eye and sheep heart. In talking to other hs moms in our area they are doing anywhere from 3-7 but our local ps has scaled back and is only doing the fetal pig in bio but the career center biomed courses are doing the cow eye and sheep heart.

 

As always the Hive has given me something to ponder for my next dc coming up.

[bugs]

I can't answer the question, however, my "non-science" daughter actually spent more time than necessary investigating the earthworm she dissected. (Not sure how she'll do with a frog :glare:.) So, for that, it was worth doing.

[Jane in NC]

This has been enlightening. I had taken the stance w/ a couple moms that I felt that labs and in particular dissections were an integral part of bio. I felt that if a student wanted to go into a science field but were hesitant to do dissections it was better to get it under their belt in high school at home than when they went to college and took Bio 101 and had to complete their first dissection. I didn't realize until I began searching the internet today that dissections were not completed in all high school bio courses and that many schools were doing only virtual dissections. We are required by our accountability assoc to show a certain number of labs and dissections are to be part of that - more are needed for an honors v a gen bio of course. I was basing my decisions on my past schooling, my oldest ds's completion of honors and AP bio in ps and my accountability assoc.

 

We completed two dissections for dd in 7th Life science - a frog and earthworm. For her honors bio this year we are doing a frog again, perch, fetal pig, cows eye and sheep heart. In talking to other hs moms in our area they are doing anywhere from 3-7 but our local ps has scaled back and is only doing the fetal pig in bio but the career center biomed courses are doing the cow eye and sheep heart.

 

As always the Hive has given me something to ponder for my next dc coming up.

 

If you look at the twelve labs that were formerly required for AP Bio (I don't know what is up with the new and improved course that has just come online), none of them were dissections.

 

The nature of how biology is taught has changed radically from my high school days when we did bunches of dissections. This does not mean that biology is not taught well--there has been a seismic shift in how the material (including so many fairly recent discoveries) is presented. As I noted earlier, we formerly learned taxonomy and approached things via systems: circulatory, respiratory, etc. If you open most modern biology texts, biochem comes before anything else. Sure we studied cells but not at the depth seen even at the high school level. Much more is known about the cellular process than when I was a student!

 

My son performed his first dissection at age 7. His specimen was a squid and he wrote his name with the ink from the squid pen. It was a great exercise for a kid. But this is not what I could consider a part of high school bio.

 

Later in high school, my son took a class at Duke on Sensory Systems during one of their TIP weekends. They did dissect a cow's eye, but the intensive weekend experience was about much more than performing a dissection. I think this is what parent/teachers have to keep in mind. Labs reinforce material--whether they include dissections really depends on the nature of the course.

 

One of the best outside classes my son took was an Embryology class in which the students artificially inseminated zebra fish eggs and then observed over several weeks the development of the embryos. Technology allows for things like this. This is another reason that dissecting pickled specimens is not necessarily the only path to travel. The home lab may not have all of the equipment available that some science centers or university summer programs do. I suggest researching options.

[Nan in Mass]

I fall into the "no dissections on ethical grounds" camp, but I would like to point out that as homeschoolers, we do have ethical options for dissection. If you aren't vegatarian, you can buy a chicken or fish, dissect it, and then eat it. This also applies to hearts and livers and kidneys (and probably some other things). If you are a vegatarian, you can look at things that have died a natural death. We didn't do any "dissections" but my children looked at plenty of dead things that appeared in our yard and they dissected a heart that then went into soup with my mother. With both these options, more care needs to be taken with sanitation, but that is a good biology lesson also. I hope the days of my mother, who was a bio major in college and was told to provide her own cat for dissection, are long, long gone.

 

Nan

[8filltheheart]

:iagree:

 

We only do dissections if they take anatomy and physiology. We do not do dissections for biology.

[Tammyla]

Dd's class did four; worm, crayfish, fish and a frog.:blink:

[elegantlion]

We will not do any for ethical purposes, plus I'm very sensitive to chemical smells. Formaldehyde makes me gag. We may view a virtual dissection, but I haven't decided. We will focus more on the modern interpretation that others have mentioned.

[flyingiguana]

None.

 

My husband teaches college bio. I used to. We just didn't feel that dissections are the major focus of what one should learn in a basic bio course. Watching living animals and plants is a lot more enlightening (if you do it right).

 

For what it's worth, my husband, the PhD, had never dissected a fetal pig in his entire undergrad/grad career. We did end up doing one together a few years ago as a favor to our church pastor who was insistent that it had to be included in a vacation church school dedicated to learning about the natural world. I had to lead my husband through it (I had done a few when teaching intro bio).

 

At the time our kids were too young to do much more than glance at it, so I don't really count that as a dissection.

 

The two dissections I did in high school biology didn't amount to much. They seemed to be more for the purposes of saying it was an honors class -- I guess they had to justify spending the extra money somehow. To be honest, I don't think I knew enough biology at the time to get much out of it. Sure, we saw a heart and lungs, but we kind of knew those would be there. I've found dissections that I did in grad school to be a lot more enlightening.

 

If you're interested in doing something along these lines, though, I'd suggesting maybe getting a sheep heart (or something large like that), and figuring out where the blood comes in and where it goes out. When I taught biology, it always seemed that students found that a lot more intriguing and helpful than merely cutting open a pig and seeing a bunch of parts. I think the pig looked so much like the 2-D pictures in their books of dissections that it didn't really tell them anything new. However, being able to hold a 3-D heart was very helpful in figuring how it worked -- something the 2-D pictures didn't do for them.

Edited March 16, 2012 by flyingiguana

[TheHomeScientist]

We will not do any for ethical purposes, plus I'm very sensitive to chemical smells. Formaldehyde makes me gag. We may view a virtual dissection, but I haven't decided. We will focus more on the modern interpretation that others have mentioned.

 

I'd be surprised if specimens you can purchase nowadays from HST and other science vendors contained formaldehyde. It's one of many chemicals that has been demonized as extremely hazardous, when the reality is that it's no more hazardous than many chemicals found in most homes under the kitchen sink or on basement shelves. That's not to say that it isn't dangerous if mishandled, but few people are going to ingest it or spend much time breathing its fumes.

 

Nowadays, I suspect most specimens are initially preserved with formaldehye (FAA, actually) and then infused with a non-toxic preservative that replaces any formaldehyde present in the specimen. There may still be a very slight formaldehyde odor, but nothing that should bother anyone who is not extremely sensitive.

[TheHomeScientist]

It seems that there's a split along YEC/secular lines here. Most or all of the YEC curricula I've seen focus heavily on dissections, while every modern secular curriculum I'm familiar with either has no dissections at all or only touches on them lightly.

[Jenny in Florida]

I clicked "other," but meant to click "none."

 

We're ethical vegans and don't believe in doing labs that contribute to the harming of animals.

 

I designed a series of labs for my daughter that did not include a single dissection. There are lots of other labs to do.

 

(She didn't do any in her college-level intro to biology course either, by the way.)

[SailorMom]

Dissections have been a highlight for our Biology study this year so for me the more the better! We've dissected a starfish, earthworm, frog, crayfish, fish and grasshopper so far. I must say that anatomy has been very much reinforced via dissection and I do not feel we have wasted any time doing the dissections we have.

. :D

 

:iagree:

I think there is a balance needed, and obviously the entire year shouldn't be devoted to dissections - but what I personally remember from my high school biology classes (regular and 2nd year advanced) are the dissections.

I do not think I'd remember anatomy nearly as well without them.

 

I personally believe hands on learning is essential, video labs do not cut it, and that anatomy is just as important now in biology as it was 20 years ago.

Sure - biochem is important, but to me that is complex and important enough to offer it as an entirely different class.....

 

Is it yucky? Yes. Smelly? Yes. Manageable if organized? Absolutely.

[SailorMom]

It seems that there's a split along YEC/secular lines here. Most or all of the YEC curricula I've seen focus heavily on dissections, while every modern secular curriculum I'm familiar with either has no dissections at all or only touches on them lightly.

 

Well - the modern curricula that is used in the public schools have taken out a lot of the "hands on" science for budget and testing reasons. This doesn't mean it's a good idea.

[SkateLeft]

None. I believe one can design a rigorous lab that does not include dissections, but focuses on other aspects of biology.

 

:iagree:

 

There's so much more to the study of biology.

[creekland]

There are no dissections in Bio classes at our school. Our Anatomy and Physiology class does cats and a few major organs.

 

My guys have done deer, chickens, fish, and shellfish. I see no need to do anything special bought for the occasion, but I want mine to know what "the insides" look like - just for life.

[Jane in NC]

It seems that there's a split along YEC/secular lines here. Most or all of the YEC curricula I've seen focus heavily on dissections, while every modern secular curriculum I'm familiar with either has no dissections at all or only touches on them lightly.

 

Interesting observation.

 

Well - the modern curricula that is used in the public schools have taken out a lot the "hands on" science for budget and testing reasons. This doesn't mean it's a good idea.

 

I thought this initially until I began comparing new biology texts to old. The latter stress biological classification through taxonomic divisions: Life, Domain, Kingdom, Phylum, Class, etc. Most working biologists today think about things through Cladistics which examine shared characteristics of organisms and their evolutionary counterparts. To understand Clades, one needs to understand genetics. The approach is very different from the way I learned biology!

[SailorMom]

 

I thought this initially until I began comparing new biology texts to old. The latter stress biological classification through taxonomic divisions: Life, Domain, Kingdom, Phylum, Class, etc. Most working biologists today think about things through Cladistics which examine shared characteristics of organisms and their evolutionary counterparts. To understand Clades, one needs to understand genetics. The approach is very different from the way I learned biology!

 

Well - sure, if you have a separate anatomy and physiology class - then the dissections would be relegated there. However, when I was in high school we were already focusing on genetics and modern biochem - but still incorporated anatomy and dissections with this. An understanding of genetics, evolution, etc., is certainly a priority - but without concrete understanding of physical organisms and characteristics, it is (imho) empty knowledge.

 

If a student has no intention of pursuing science in college, I can see where dissections could (maybe, sorta kinda) be considered optional, but I think those students are missing out.

[Jane in NC]

Well - sure, if you have a separate anatomy and physiology class - then the dissections would be relegated there. However, when I was in high school we were already focusing on genetics and modern biochem - but still incorporated anatomy and dissections with this. An understanding of genetics, evolution, etc., is certainly a priority - but without concrete understanding of physical organisms and characteristics, it is (imho) empty knowledge.

 

If a student has no intention of pursuing science in college, I can see where dissections could (maybe, sorta kinda) be considered optional, but I think those students are missing out.

 

I see your point. And I am not necessarily anti-dissection. It is just that there are so many other interesting lab possibilities for biology that I think one can consider options.

[TheHomeScientist]

Well - the modern curricula that is used in the public schools have taken out a lot of the "hands on" science for budget and testing reasons. This doesn't mean it's a good idea.

 

Actually, it's just the opposite. Dissections are cheap. When I took my first biology class in 9th grade more than 40 years ago, it focused very heavily on dissections. The tools were cheap and could be (and were) used year after year, decade after decade. Specimens were cheap. But we didn't do all those dissections because it was the best (or even a good) way to learn biology. We did them because microscopes, even student-grade ones, were extremely expensive. Our classroom/lab had only one or two of them for 30 students. And it's not much better today, although decent microscopes now cost a small fraction of the price in real dollars that they did 40+ years ago. It's still very common in public schools to have four or more students sharing a microscope.

 

The problem with dissections is that they put the cart before the horse. I have no problem at all with students doing dissections, but they shouldn't be doing them until a second or third year biology class in gross anatomy/physiology. Doing them in the first year is focusing on the whole before students understand much about the parts that make up that whole. A first-year biology class really needs to focus on the chemistry of life, life processes, cell division and replication, cell structures, unicellular organisms, and so on, with survey sections on prokaryotes, protista, fungi, plantae, and animalia. I think it'd be very tough to get as far as organs and organ systems, let alone macroorganisms, without shortchanging all the preliminaries.

[TheHomeScientist]

I thought this initially until I began comparing new biology texts to old. The latter stress biological classification through taxonomic divisions: Life, Domain, Kingdom, Phylum, Class, etc. Most working biologists today think about things through Cladistics which examine shared characteristics of organisms and their evolutionary counterparts. To understand Clades, one needs to understand genetics. The approach is very different from the way I learned biology!

 

Exactly. Bottom-up is much better pedagogically than top-down. Cladistics and phylogenetics have revolutionized biology, but a lot of biology texts, including recent ones, are stuck back in the days of phenetics.

[FaithManor]

Not necessary. That said, some students benefit greatly and especially in the area of learning anatomy and physiology.

 

To be honest, dissections are more common for zoology majors than pre-vet majors.

 

I was not planning a bunch fo dissections this year, however, some of the students where I work have BEGGED for dissections. They have immense curiosity and none of them are squeamish. Since they've had a paltry science background, I've decided to capitalize on that enthusiasm. So, despite not planning any, I leave in 10 minutes to dissect crayfish and squid with 9 students. :D

 

Next week are beginning a bacterial growth project that includes culturing samples from the bathrooms, doorknobs, and drinking fountains. It's an excellent thing that I have a curious bunch who are not afraid of ick! :biggrinjester:

 

Call me the hypocrite! You don't need them and I'm leaving to teach them.

 

Faith

[elegantlion]

I'd be surprised if specimens you can purchase nowadays from HST and other science vendors contained formaldehyde. It's one of many chemicals that has been demonized as extremely hazardous, when the reality is that it's no more hazardous than many chemicals found in most homes under the kitchen sink or on basement shelves. That's not to say that it isn't dangerous if mishandled, but few people are going to ingest it or spend much time breathing its fumes.

 

Nowadays, I suspect most specimens are initially preserved with formaldehye (FAA, actually) and then infused with a non-toxic preservative that replaces any formaldehyde present in the specimen. There may still be a very slight formaldehyde odor, but nothing that should bother anyone who is not extremely sensitive.

 

That's good to know.

 

 

We have done a lot of nature study over the years. Where we used to live we would observe living nature all the time. In fact we quit planning it, because it would come to the door, literally. Frogs, snakes, alligators (yes!), dragonflies, bees, lizards (lots of them), birds, even a fox and a heron. We found a few dead ones (thankfully no alligators!) over the years and have studied them. I offered to dissect a frog we found, but it just grossed ds out.

 

As we head into our high school years, I definitely see the benefit of nature study in the younger years.