The world is closer to a major conservation target than scientists thought

Counting conservation areas

0:00Welcome back to the Nature Podcast. This week, how the world's conservation areas may be undercounted, and what AI is revealing about brown fat. I'm Benjamin Thompson, and I'm

0:36Nick Petridge-Howell.

0:45Putting aside land where animals and plants can thrive is a key way to conserve them. These areas can protect fragile ecosystems and help rare species thrive. And because of this, nations have agreed to turn 30% of land into conservation areas by 2030. If you look up the official statistics on how close we are to that, you'll find that current data suggests that the total area is only 18.5%, quite a way to go in the next four years. According to new research

1:17though, humanity may be much closer to that 30 by 30 goal than current data suggests. But even if we're closer than we thought, it may not actually solve all the issues that biodiversity is facing. To take us through the statistics, I caught up with one of the authors of the new research in nature, Bob Smith, who told me why it was that he suspected that the official numbers were off. So a big part of it actually comes from doing fieldwork and knowing that the official data can sometimes be a bit different to what's happening on the ground, especially as there's a new type of

1:52conservation area called an OECM, which stands for Other Effective Area-Based Conservation Measures, where they're managed in a way that they have conservation benefits, but where conservation isn't necessarily the primary management objective. So the most famous of those are areas often in the rainforest, governed and managed by indigenous peoples who live there, farm there, but to them it's important to manage the land in a way that maintains the rainforest or the other habitats,

2:24so that they're really important for biodiversity as well. So in the past, there was a real focus on protected areas, which are often run and managed by the government. But as part of meeting this 30 by 30 target, there's a big push to start broadening out the types of conservation areas that should be internationally recognised and included in these reporting. And so this analysis involved talking to our colleagues in a set of countries to say, basically, please send us all your data, send us the data that you have on those conservation areas that at the moment isn't

2:55recognised internationally. Together we'll go through it and work out which of those sites could count as one of these OECMs and that will eventually count towards that 30 by 30 target. And was it as simple as, well, I say simple, was it as straightforward as asking everyone for their data and then compiling it together? How did you actually come up with a new estimate? Yes, I mean, actually, the analysis itself is pretty simple. You know, we chose a representative sample of countries, 25 countries and territories that cover 10% of the land. And we just contacted all

3:29those people to bring the data together. Contacting those people, getting the data, cleaning it up, combining it, took ages. Tracking down people who might have data on particular data sets. I mean, almost certainly there are other data sets out there that we didn't get hold of. It really was a case of going through different networks and finding people. So there's almost certainly gaps there as well. But once we have the data, it was relatively straightforward just to do spatial analysis, adding that up together and just assuming because our 10% sample

4:03is representative, that we can extrapolate to the whole world based on the 10% sample. And when you compiled all this data, what did you get for the estimate of the areas of the world that are under conservation? So we looked at three categories and actually one of the things that we wanted to do was use the official data. So we had what we called globally recognised protected areas. So those are the existing ones. Then we have nationally recognised protected areas, because in some countries there are still government protected areas or private protected areas that are recognised at the national

4:35level, but that don't meet the global definition of what a protected area should be. And we thought those are actually likely to count as these OECMs, this other type of conservation area. And then we looked at what we called possible OECMs. So these are the sites that we think meet the OECM definition that haven't gone through that official recognition process. And based on that, we think we're just under 27% coverage when you combine those three types of conservation area together.

5:06And so, you know, obviously, as you say, it sounds like we're fairly close to that 30 by 30 goal. Do we just rest on our laurels now? Are we done? Conservation solved? Definitely not. Yes. I mean, on the one hand, you could see this is really positive. It means that we're close to 30 by 30, but biodiversity nature is still massively in decline. So that really focuses on the fact that the area you've got under conservation is much less important than how well that area is managed. And there's a big recognition that most conservation areas around

5:39the world are really underfunded, don't have the staff, don't have the equipment. And so it's a common message throughout the sort of conservation area community. We really need that investment to turn that around. And our paper flags up that while the area component is keen, if you've just got large areas of land that are missing out on all those other elements, we're not going to reverse biodiversity loss. There's also the worry, which I think is a very valid one that, you know, some people say by fixating on meeting the area target, often governments don't put any more money in.

6:15So actually the money per area, per national park, per game reserve gets spread even more thinly, and you might actually have even worse conservation outcomes by just focusing on the area part of the targets. So what to your mind should be done then? Is it a case of just more funding or is there something more targeted or something more specific that you would like to see? More funding would really, really help, but definitely there are other things too. So this approach that I use and lots of colleagues use for identifying where new protected areas should be is designed to make things a lot more

6:47targeted. We really need for countries to use approaches that identify where the gaps are and focus on filling them rather than just doing more of the same. So in a more systematic way, tackling those issues of making sure that your sites are connected and contain the important biodiversity and represent all the biodiversity found in the country, as well as the issues related to management effectiveness and governance. If you want someone to take one thing away from your paper, what would that be?

7:18The fact that we need to put more effort into recognising and accounting for these different types of conservation area. Like I said, this took a long time piecing all these things together. And yes, coming up with processes that actually engage with those people so that that data is available and those people are recognised more, yeah, I think would be great both for understanding what's going on, but also for giving them much better recognition at the global level than they do at the moment. So are you optimistic about the future then? Perhaps it sounds like some of these newer conservation

7:52areas could try and meet some of these targets a little bit better than perhaps others have in the past. Yes, I'm optimistic in terms of things will get better. The big issue is that they need to get better quickly. And so that's where the struggle is. That's where we need the resourcing. Countries need the funding. There needs to be that political will to make sure that we get to a point where actually conservation areas are achieving everything that they could be for people and for nature. That was Bob Smith from the University of Kent here in the UK. For more on that story,

8:24check out the show notes for some links. Coming up, what a huge data set and artificial intelligence have revealed about the mysteries of brown fat in humans. First though, it's time

Research highlights on space and brains

8:36for the research highlights with Dan Fox. The sun's tumultuous death throes could spell the end of our solar system one billion times sooner than was previously thought. Although thankfully, we've still got a while to go just yet. In a few billion years, our sun will die. First, it will swell into a giant, puffy ball of gas and plasma before expelling roughly half of its mass by shedding its outer layers. Astronomers have long

9:09thought that this process won't disrupt the harmony of the planet's orbits, but their models have represented this loss of mass as a smooth, continuous process. In reality, the sun's demise will be anything but. Instead, it will eject mass in random, discrete bursts that will slightly change the star's velocity each time, tweaking its gravitational tug on the planets. A team of researchers have now used numerical simulations to model how this random mass shedding will affect each planet's orbit.

9:40They found that in the one billion years after the sun begins its transformation, the planets could be jostled enough that their orbits will overlap and become destabilized, dramatically reducing the previously theorized one-quintillion-year life expectancy of our cosmic home. That's still plenty of time to read this research, though. It's in the Astrophysical Journal Letters. Human brains tend to start losing weight around the age of 45 to 50, even in the

10:12absence of disease. Now, a new analysis of chimpanzee, gorillas, orangutans and bonobos suggests that this weight loss doesn't happen in our closest living relatives. Scientists analyzed data from zoos, research centers and brain repositories on apes' post-mortem brain weight. The animals ranged in age from 4 to 70 years old and 63 of them were older than 50. They found that older animals did not have significantly lighter brains than younger ones did,

10:43and there was no sign of a drop in weight emerging later in life. That's notable because earlier studies have found protein deposits related to Alzheimer's disease in the brains of older apes. The results could mean that the great apes studied are able to maintain brain mass despite other age-related processes taking place in the brain. The authors suggest that the marked drop in brain weight in humans could perhaps be linked to our longer lifespans. You can read that research in the Proceedings of

11:14the National Academy of Sciences of the United States of America.

Uncovering brown fat mysteries

11:19Next up on the podcast today, we've got a story about an unusual type of body fat, known as brown fat. Now, body fat often gets a bad rep, but brown fat is unusual, as it's a type of fat whose activity is associated with decreased prevalence of things like cardiovascular disease. Researchers and clinicians are hoping to use this tissue's properties to help protect against a variety of health conditions. But there's a lot that isn't known about exactly what these might be.

11:52This week in Nature, a team of researchers has tried to better define what effects brown fat might be having on the human body and potential ways to increase its activity. Mariana Lenaro has been covering the story for Nature, and she joins me now. Mariana, thank you so much for being here. Thank you. It's great to be here. Well, let's start at the start, I guess, and talk about brown fat, because it's a very particular sort of fatty tissue in the body. Right. So when we think about fat, we usually think about that jiggly tissue around our bellies.

12:24So that's white fat. Brown fat does something opposite to white fat. So white fat saves energy, saves calories from what we eat. And what brown fat does, it actually consumes calories. Right. So it's kind of like a heating system, like it devours sugar to make heat. Yes. And it has been shown throughout the past decades of study that it has several benefits for health related to metabolism. So it not only produces heat, but it also has all these other metabolic

13:00positive effects. And so a lot of what is known about brown fat and its potentially positive effects on things like the cardiovascular system are known from rodents and animal studies and what have you. And the fact that brown fat exists in human adults at all is actually a relatively recent finding, and not everyone has detectable levels of it. So what is this new research trying to find out? Yeah. So the first time that brown fat was identified in human adults was in 2009. And since then,

13:32researchers have been trying to find what are the effects of brown fat in humans. So a previous study showed that there was an association between having active brown fat with having a lower risk of type 2 diabetes, hypertension, and other cardiovascular disease. This new study builds on that work, and it looks at more than 100,000 people who were going through cancer treatment and diagnosis. And as

14:03part of that, they had their body scan. And that's the same type of scan that can also determine whether they have or they don't have brown fat. And so the researchers behind this new work then combined the data from these scans with other aspects of these people's medical records to work out what effects having brown fat or not having brown fat might have. That's exactly right. So they looked at all other diagnoses that those people have received throughout their lives. And they saw that not only those who had brown fat had a lower prevalence of metabolic

14:40conditions like type 2 diabetes, hypertension, and other heart conditions. But also surprisingly to the authors, they also had a lower risk of anxiety and depression. And so this kind of chimes with what researchers, including these researchers, have seen before. But in this work, the team does something a bit different. They use an AI system to look at these images, and they're looking at more than just the absence or presence of brown fat, looking at maybe what it

15:10might be doing. Is that right? That's correct. So they used an AI model to quantify the amount of brown fat activity present in the people. So the previous studies were more binary. So they either saw that the person had active brown fat or didn't have it. In this case, they're quantifying the amount of brown fats in the images. And in this case, they were able to see that the more active brown fat people had, the more benefits they've experienced.

15:41And AI is becoming a lot more prevalent in image analysis in the kind of medical field and sometimes throws up unexpected results. Did the AI in this instance uncover anything unusual that researchers didn't know before about brown fat in the human body? With this analysis, they were able to identify exactly in which areas of the body brown fat has the most positive effect. So they saw that the area that is more associated with health benefits was the

16:12region around the armpits, which people didn't know before. So that's something surprising and unusual that was uncovered by this analysis. And one of the puzzles with brown fat that I alluded to earlier is that some people have it, some people don't. And it can be vanishingly rare, right? A very small amount of the total fat in someone's body. And so working out ways to get it working or to increase its amount is, from what I understand, quite an important part of research in this area. And in this work, have they made any

16:44strides in that aspect? Very little is known about how to stimulate or brown fat or how to get more brown fat if it has those positive effects. So what the researchers did was look for the drugs that these people were taking to see whether they could find any possible associations between getting a certain drug and having brown fat. And they did find an association between the use of this class of drugs called angiotensin receptor

17:16blocker. So this class of drugs is used to lower blood pressure. And one of the popular drugs in this class is Lozartan. So they found this association and then asked, could this drug help to activate brown fat? Is that why we're finding this association? So they were able to show in cells and in animal models that this drug, Lozartan, does indeed seem to activate brown fat. So this opens up the possibility to use this drug or a variation of

17:51this drug to stimulate brown fat activity in the future. So that's an exciting thing to come out of

Future treatments and caveats

17:59this study.

Future treatments and caveats

18:00But of course, there are caveats to this work. This is a retrospective study looking back at previously collected data from a very particular group of people who are undergoing treatments for different sorts of cancer. What have folk told you about the results as they've read them? It is a retrospective study. So I've heard from people not involved in this work that it is a very interesting finding, but it would need further investigations to see if this would be the case in other populations. But it's also very challenging to do prospective studies in this

18:35area because this imaging technique, it involves radiation. These are cancer patients that need to be scanned in order to monitor their disease. It would be much harder to get people who are otherwise healthy to receive those scans in order to study specifically brown fat. But people were really impressed with the number of participants and really impressed and surprised with some of the

19:06findings coming from the study. And of course, some of these results need to be treated carefully as well. I mean, the researchers, as you've mentioned, found this association between things like having brown fat and lower levels of anxiety, for example, which of course needs to be taken with caution. What have folks said to you about that? It's not completely clear why that association would happen, but there are some small studies showing that people who, for example, do cold swimming, they report having a better mental health,

19:38lower levels of anxiety, and exposure to cold is something that can stimulate brown fat activity. But all of these studies are really small because not a lot of people would want to participate in those studies. And quantifying and identifying brown fat itself is challenging because of the technique that is used. So at this point, it's a bit speculative. So finally then, Mariana, there's been a lot of interest in brown fat in human adults since it was

20:09discovered. Where does this research fit in? And what's maybe the field hoping it could ultimately be used for? Researchers envision brown fat activation to be used in the future as a sort of a complement to GLP-1 drugs. So people achieve these impressive weight loss results from GLP-1 drugs, but we know that the weight tends to come back when they stop taking these drugs. So because brown fat is associated with increasing, enhancing people's metabolism,

20:46researchers think that it might be used as a complement after people have already lost their weight. They might then use some sort of strategy to enhance their brown fat in order for them to keep their weight down and continue having health benefits associated with a better metabolism. Nature's Mariana Lennaro there. Head over to the show notes for links to her story and the research paper we talked about. And that's all for this time. If you'd like to stay in touch with us, you can. We're on email,

21:18podcast at nature.com, or you can find us on social media, at naturepodcast. I'm Nick Petrich-Howell. And I'm Benjamin Thompson. Thanks for listening.

21:36Thank you.