When There Isn’t a Simple Answer with Prof. Dennis McLaughlin (S3:E4)

Key Takeaways

[Music] students come in with opinions already and they can say things in a seminar that are based upon just their common knowledge and not based on the readings today on chalk radio we're exploring global food production water and climate change and the challenge of teaching when polarized opinions come to class i'd say generally the students learn that most of these issues are more subtle and complex than they thought when they came in the class so one of the things that happens at the end of the class is people's opinions are usually not as polarized as they were in the beginning i'm kurt newton your guest host for this episode of chalk radio at mit officially i'm director of mit opencourseware but for so many years at mit and in my personal life i'm also doing a lot of work on climate change so when sarah hansen your usual host lined up this episode dealing with these issues that are so deeply personal for me around climate change food systems and water and gave me the chance to join in i jumped at it with prolonged droughts made worse by climate change affecting food production and ecosystems all around the world this conversation couldn't be more timely our guest dennis mclaughlin is a professor in mit's civil and environmental engineering department and he's the instructor for course 1.74 land water food and climate professor mclaughlin's interest in hydrology and what it can tell us about our food systems has been years in the making it all started back in 1991 on a research trip that took him halfway around the world i went to australia and there were a lot of discussions at the time about what was sustainable food production and whether or not australia could grow more food with limited water and the connection between the availability water and the population and food supply struck me as a really interesting application area for hydrology dennis explained that some of the big wheat growing areas were becoming reliant on irrigation to supplement natural rainfall with water pumped from underground in order to keep the crop big and healthy but over time all that irrigation causes salts to build up in the soil you could go out in the fields and see near the irrigation ditches just white layers of salt accumulating it's the same kind of problem that ruined mesopotamian civilization you know millennia ago and it wasn't like it was a big surprise but there was not really a good mechanism to encourage farmers to hold back on their irrigation there was a lot of interest in changing regulations and incentives for farmers to have less adverse environmental impact especially with salinity and to make sure that there was enough water to keep the agriculture economy healthy and going i mean it's not a reasonable solution to say we won't have any more farming and therefore we won't have salt accumulation and so on so it's that balance between sustainable use and economically productive use that's tricky this experience in australia led to the creation of a course on water usage and agriculture and food systems it was here where professor mclaughlin recognized that teaching these topics can bring about an extra challenge one of the interesting things about the course and a challenging thing as a teacher is a lot of the topics we talk about sort of like talking about climate change rgmos our food waste our vegetarianism students come in with opinions already and they can say things in a seminar that are based upon just their common knowledge and not based on the readings so for example in gmos the focus of most of the students is oh gmos hurt me human health are they going to cause me to have cancer or whatever and that's really not the scientific perspective so much in gmos because there's almost zero evidence that any gmos are harmful to human health and they learn that by reading the papers the problem is what do they do to the ecosystem and what do they do to other plants that are not genetically manipulated and what are the unintended consequences of gmos because gmos are generally designed to help the farmer be more productive one of the things that happens at the end of the class is people's opinions are usually not as polarized as they were in the beginning in my own work on climate change i've certainly had this experience of trying to have conversations with people coming out of polarized opinions and preconceived notions i was really curious to hear how dennis moved beyond that in this class and helped the students have more productive conversations view these sometimes controversial issues from multiple angles it's really just an introductory course and it's to kind of stimulate interest that they had when they came in and show them that it is possible to pursue difficult topics by going to the literature many of them aren't used to reading scientific papers the undergraduates especially they're used to being lectured to and things being in textbooks and here's where dennis mclaughlin gets creative for each article he assigns a student is asked to present that article to the class but dennis also gives a specific prompt to make sure that these presentations actually help the students understand the material another challenge in the course is to make sure that their presentations don't bore the other students so i said you just have a minute or two and you should pose some questions for the class or some issues and make them as controversial as possible so that's that's what we try to do as controversial as possible wouldn't encouraging controversy just prevent us from moving beyond polarized opinions dennis went on to explain why controversy really is productive and important to deal with especially in science and engineering classrooms another thing they're not used to the students even some of the graduate students is scientific controversy there's perhaps not that much controversy ironically interestingly about gmos but there's a lot of controversy about things like organic farming and whether or not we should be willing to sacrifice yield a bit to have more sustainable agriculture and one of the things we find out in the class is many people who are organic farming advocates are sort of out of the mainstream of the scientific literature but when you review the papers on the other side that say for example it's silly to try to continue smallholder farming in africa africa's agricultural future should be large industrial farms perhaps run by foreigners who buy or lease the land so people write assessments like that and you say well yeah but they're being funded by the large agricultural industry well does that mean they're wrong are they biased well i don't know but they become advocates too so the students read the papers and we try to discuss both sides of an argument uh based on the merits and um i'm not saying students don't get exposure to that kind of thing elsewhere but if they're taking physics and we're talking about newton's law you know it's not presented as a controversy motivating students to engage with the scientific literature to unpack controversies is only part of the work involved in teaching this engineering course there's something else too something really important it's a challenge to decide how much effort and discussion to spend on learning about scientific issues scientific controversies more or less agreed on facts and how much to spend on things like values because you really can't talk about smallholder farming unless you talk about poverty you can ask questions so why is the smallholder farmer so poor why does the smallholders kids not want to stay on the farm they want to go to the city what do they do in the city are there jobs there well do they have any education well no because the smallholder farmer doesn't have enough money to send the child to school what about the role women in farming and the role of cultural differences in how women are viewed and can they for example participate in ownership you could just spend the whole semester talking about this stuff dennis's course attracts students from a wide variety of disciplines and backgrounds and it's this diversity of experiences among the students that enriches the class for everyone including dennis i had a student in the last class who was an art student at mass college of art and she knew almost nothing about engineering or science but she came from venezuela and settled in puerto rico and her aunt is a farmer and so she talked about how hard it was for puerto rican farmers to be competing with central american farmers who were very poor who were exporting produce to puerto rico so puerto rico this place where you can grow food all the time this very productive climate is not producing much food for its own residents because of pricing and she actually brought that to the class and talked about it and i i wouldn't even thought about it so there's this interaction between the students who have had farming experience or just a student from puerto rico who's talking to one from philadelphia and they're both from cities but they have a much different perspective so not only did the other students learn from these students but i learned from them as you may have picked up by now climate change is an important topic in this course we asked dennis how climate change will affect food and agriculture well that sounds like a question we could pose in the class and we do discuss it through reading papers so this is a big topic and a controversy one um one thing that there seems to be pretty good agreement on is if climate change increases temperatures during the growing season sufficiently that will hurt agriculture but it depends on the crop depends on the place it's a lot different talking about small increases in average temperature versus large increases that could actually reduce yield or even kill crops so temperature extremes probably won't help this course really pushes its participants to look beyond their own assumptions questions contradictions uncertainties those are inevitable when we take on topics as complex as food water and climate change professor mclaughlin embraces that questioning as a core part of the class even as he tries to provide some answers especially undergrads they're used to going into class and thinking they're learning quote facts and that's the end of the story but i view the teacher as kind of adjusting resetting the discussion to keep things kind of on track and consistent with the papers but giving the students the freedom to say silly things or to go beyond the scope of the paper is part of why they like the course when they learn that their differences of opinion even among experts and that their values value judgments and that their social equity and all kinds of things and i can't i you know they don't even connect that really with formal education but it's not so easy because for one thing it takes the students off balance a bit so it's definitely an art and you learn it over multiple times you can't just start the very first year and be perfect on it so you have to learn the teaching style as well as the content you have to teach yourself how to be observant to what works and what doesn't [Music] maybe we can all take a page or two from professor mclaughlin and his students get a little more comfortable being knocked off balance dennis's perspective made me wonder how other educators handle similar situations how do you integrate conversations about values and culture into your science and engineering courses in a way that feels balanced you can share your insights via the link in the show notes and we'll pass them along to mit faculty and listeners who could incorporate your ideas into their teaching [Music] if you're interested in learning more about professor mclaughlin's work or teaching with his open educational resources you can check out his course 1.74 land water food and climate on our mit open courseware website it's one of over 150 courses in ocw's extensive environment courses collection and for even more check out the mit climate website at climate.mit.edu where you'll find a wealth of material spanning these topics and more thank you so much for listening until next time signing off from cambridge massachusetts i'm kurt newton from mit open courseware chalk radio's producers include sarah hansen brett pachi and dave lachansky scriptwriting assistance from nidhi sastry show notes for this episode were written by peter chipman we're funded by mit open learning and supporters like you