Short Wave - Redlining's Ripple Effects Go Beyond Humans

Episode Date: January 9, 2023

When Dr. Chloé Schmidt was a PhD student in Winnepeg, Canada, she was studying wildlife in urban areas. She and her advisor Dr. Colin Garroway came across a 2020 paper that posed a hypothesis: If the echos of systemic racism affect the human residents of neighborhoods and cities, then it should affect the wildlife as well. Short Wave Scientist in Residence Regina G. Barber talks to Chloé and Colin about their findings of how redlining and biodiversity are intertwined.See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Think about your neighborhood. Can you see it now? Are there lots of trees, parks, sidewalks? Or is there a lot of concrete? Are you close to a highway? What animals do you see in your backyard? Who lives near you? Well, if you live in the U.S., odds are your neighborhood may still be experiencing the aftermath of a policy called redlining. Dr. Chloe Schmitz at the German Center for Integrative Biodiversity Research says it started in the 1930s. That was when this homeowner's loan corporation was established and they essentially said agents out across cities in the U.S. to, you know, write reports on and grade the quality of different neighborhoods. And so there were just a lot of zoning and loan and, you know,

mortgage practices that were all based on these grades. And so if you were, for instance, a black person, and you were trying to buy a house in an area that was graded A, you still just were not able to buy a home in those areas. And so it was finally outlawed in 1968 with the Fair Housing Act, but a lot of the times the racial composition has still persisted from these practices. When Chloe was a Ph.D. student in Winnipeg, Canada, she was studying wildlife in urban areas. She and her advisor Colin Garraway came across a 2020 paper that posed a hypothesis.

If the echoes of systemic racism affects the habitats and overall environments of cities, then it should affect the wildlife as well. Our minds were kind of blown and we were like, wow, this would be really, really cool to test. And it's such a straightforward hypothesis with straightforward expectations. And we kind of already had the data ready to go to be able to test it across the U.S. They used data from other studies, looking at 39 species of animals at 268 locations in cities across the United States. Then Chloe and Colin put together a picture

of how history can shape how all living creatures in cities thrive. Or don't. Today's show, I talked to Chloe and Colin about how systemic racism can affect biodiversity of wildlife in cities. I'm Regina Barber. You're listening to Shortwave,

the Daily Science podcast from NPR. Chloe and Colin wanted to get as much data as they could to see if there was a correlation between racial makeup of a neighborhood and the health or biodiversity of the wildlife populations in those areas. Can you explain what you did with that data? So, like, what animals did you look at?

Like, what data did you take? We started with mammals and collecting them in the U.S. and Canada, just because there's been a lot of studies done there. So there was a lot of data available. And then we eventually expanded to just all terrestrial vertebrates. So we've got mammals, we've got birds, amphibians, reptiles, And amongst mammals, we've got everything from mice to deer to bears and, you know, birds. We've got chickadees to ducks and geese.

And, you know, there's all sorts of kind of random species in there. Yeah, what did you find? We found that wildlife populations, so from across mammals, amphibians, reptiles, birds, the populations that lived in areas with higher proportions of white residents tended to be bigger and they tended to be more well connected. And both of those things are super important from an evolutionary perspective because, you know, bigger populations tend to be more resilient to kind of environmental changes that if there's only a couple individuals in there, they might get totally wiped out.

and then bigger populations also tend to have higher genetic diversity, which is what we found. And having more diversity, having more individuals moving around between populations and sharing genes, this is all good for long-term population persistence because that's the raw material that evolution has to work with to be able to adapt to environmental changes. and, you know, those are happening in cities just all the time. And so it's quite important for urban populations. I think a lot of people will be like, well, maybe it's not racial, maybe it's economic. But you both were like, no, it's racial, not economic.

Can you tell me a little bit more about that? Redlining was not based on wealth. It was based on race. If you were part of a group that was being forced to live in a particular neighborhood, you were forced to live there regardless of your wealth. And then there are certainly economic disparities, but the way we think about it, and I think the way it's thought about in the literature, is that systemic racism is a common cause of both wealth inequities and in this case, environmental disparities as well.

I just want to add that, you know, an area might have a high median income, but where the parks get place and kind of where street trees are is a municipal decision. And so it's how much the city wants to invest in these different parts. And so redlining caused differential investment in greening different parts of cities. And you know, that was another choice that someone made. And so to say that this habitat quality is, you know, strictly a product of socioeconomics and income just isn't really the full picture. So, Chloe, what was then surprised? So, Chloe, what was then surprised? to you about the results? Or was it surprising? Well, it was both surprising and unsurprising. I think, you know, given the consistency with which these policies were applied across the country, we did

suspect that we would see these patterns. But I don't think either of us really thought it would fall out the way it did, you know, because in evolutionary terms, that's a relatively recent change, you know, from the 30s until now, you know, for evolutionary time. It's not very long. And so I think the fact that we did pick out the effects that we expected to find was a little surprising and also a little sad. All of these species had higher genetic diversity in these neighborhoods with higher proportions of white residents. And so to see those effects so consistently across all these different species was actually quite surprising to us. So, Colin, what do you think is the most important result you hope people understand or take away from the study?

It's really clear that it's a result of differential investment in green space, different policies related to pollution and building. And this is something that we can change our mind about. We can plant more trees. We can pollute less. And we're talking lots about genetic diversity here, but genetic diversity is linked to just the size and number of animals in biodiversity in neighborhoods. So by refocusing and careful planning, we can increase the number of animals in everybody's neighborhoods. So yeah, this highlights a problem and inequity, but also a solution.

Chloe, why is a more biodiverse ecosystem or a more biodiverse wildlife population important for the human population in that same area? We're talking a lot about genetic diversity and things, which is kind of an abstract concept, but we could think of it as almost an indicator of the habitat quality. And if we know that people also benefit from green space and, you know, seeing wildlife and biodiversity around, then the fact that we're able to detect these effects of habitat quality on population genetics really means that there's a problem, you know? And I think that it's very clear from a lot of different sources that these differences in habitats exist. and that they are bad for human health. So, you know, in addition to, you know, having less green space, we also know that neighborhoods with non-white communities

tend to be located closer to, like, toxic waste dumps or highways. But I think that's starting to be more recognized and accepted now that this was a product of human choices and that it's going to take kind of a similar direct and effective. choice to reverse it. And I will say that actually that's one of the Biden administration's stated priorities. It's really specifically focused on environmental justice and getting equality and just environments where people live. And so hopefully with kind of systematic efforts like that, we'll be able to turn this around. Racism is a topic many people

are uncomfortable talking about, right? So you talked about how once this paper came out, you're worried about social media. You're worried about backlash. Can you tell me like a little bit more about that? And then tell me how the paper actually was received. Yeah, I was, I was extremely worried. I'm a biologist. I don't usually engage with these sorts of topics. And I definitely don't do anything that could be construed as controversial. And since the paper has come out, yeah, my fears were completely overblown. There were a few stray comments here and there on Twitter, but really nothing compared to what I was expecting. And really, it's, I think, at least in my experience, from what people have told me, it's been well received, people are really interested. They

think it's really important because, you know, cities are places that humans have made. It's, it's all down to our choices. They think this is an important aspect that needs exploring. And if it make some people uncomfortable? Like, it's still there and we still need to understand how it works. So actually, the biggest road bumps we had in getting this paper out was during the review process where it was very awkward because, you know, we had a reviewer who was almost, I don't know, personally mad because I think they assumed that two white Canadians were writing this paper about systemic racism in the U.S.

And we got the idea they're thinking, what business of it is theirs, you know, who are, who are they to be writing about this? And yeah, so I mean, the paper was initially rejected at first and that was part of the reason. And so, you know. How did you reply? Well, I mean, first of all, we had to come back and it's maybe assumptions about people based on their name and current affiliation aren't great.

You know, I'm like, I'm American. I am mixed race. And so it was just a, I was very personally offended after reading those reviews. And I mean, not just offended, it's just insulted. And so, yeah, that was honestly the weirdest part and why I was expecting more backlash, to be honest. In this paper, we don't talk about how people should feel or other things. So I think who says what does matter? Like there's things that I wouldn't and shouldn't say.

but we were very careful in this paper and it's Chloe's paper. So this was like a completely inappropriate review that we submitted a formal appeal to the journal and it was appealed and then they reconsidered. And then things went more smoothly after that. And this review really didn't focus on the content of the paper. That's what set us up for the expectation of backlash probably more than anything, eh, Chloe? Yeah, for sure. Yeah. That made me extremely nervous.

I mean, they had me questioning if I was a person who should be writing the paper, you know? Yeah. And who can't, right? Yeah. I mean, honestly, a small part of me wants it out there just to know that you shouldn't make these assumptions about people. But, I mean, of course, it is important who are the people writing the paper. But, you know, where do you draw that line? I don't know.

So it's complicated. I know. Yeah. You know, that's another thing with this because I'm a biologist. I'm not a sociologist. And so, you know, a lot of times we're wondering, are we qualified? Are we the person to do this? But because we were really just focusing on the wildlife and genetics, we felt we were, you know, on solid ground and that it was a straightforward question just happened to be about race. We obviously don't want this, you know, overwhelming the rest of the main message.

Chloe and Colin both say they want to continue this kind of research and have even talked about collaborating with people outside of biology or ecology. Colin says in Canada redlining existed in different ways, and some preliminary research has shown hints of the same patterns they found in the U.S. This episode was produced by Rebecca Ramirez and Giselle Grayson. It was edited by Giselle Grayson and fact-checked by Ubi Levine. Josh Newell was our audio engineer. Brendan Crump is our podcast coordinator, Beth Donovan,

is our senior director, and Anya Grenman is our senior vice president of programming. I'm Regina Barber. Thanks for listening to Shortwave, the Daily Science Podcast from NPR.