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Forwarded this email? Subscribe here. 🆕 OUR RECENT PUBLICATIONS A 73% average decline in wildlife populations: an overview of the 2026 Living Planet Index report The 2026 Living Planet Index report is published today. As with previous additions, it can make for a depressing read. The headline is a 73% average decline in wildlife populations since 1970. Declines in global biodiversity are extremely concerning, but many of the news headlines you’ll see today will probably report this latest result incorrectly. At least they have in previous years. Some may report that the world has lost “73% of animal populations since 1970” or “73% of species are in decline”. Neither of these is correct, and the report’s authors go to great lengths to stress this. Instead, the Living Planet Index captures the average decline in population numbers across almost 36,000 populations. These changes are then averaged using a geometric mean and given different weightings in the final index. It’s a bit more complicated than a “we’ve lost 73% of wildlife” headline might suggest. When we dig beneath the headline number, we find that around half of the studied populations have declined, but just as many have either increased or remained stable. In this article, we look at what the Living Planet Index does and doesn’t capture, and what’s changed since the last report. Read Hannah’s article What impact will climate change have on malaria? Malaria is a very temperature- and rainfall-sensitive disease. This means it’s one whose distribution and severity could change a lot in a warming climate. This is particularly worrying because the global burden of malaria is so high: it kills more than 600,000 people a year. Almost half a million of those are children. What effect has climate change already had on malaria, and what impact could it have in the future? In this article, we draw on a recent paper by Colin Carlson and colleagues, published in Nature, which attempts to answer this question. They find that, over the last century, climate change has likely increased the prevalence of malaria in children across Africa by a rate of 1 case per 1,000 children. To put this into context, there were around 240 cases in every 1,000 children in this region at the time. So, the impact has been relatively small and is uncertain. The bigger impact has been the change in distribution. Malaria rates have likely decreased in West Africa due to climate change. This is because warming has pushed temperatures in this subregion beyond malaria’s optimum temperature of around 25°C. In other parts of Africa, higher temperatures have pushed it towards the optimum, increasing the prevalence. Overall, the impacts of interventions to reduce malaria — bed nets, antimalarials, and improved healthcare — have far outweighed the impacts of climate change. These dynamics are expected to stay the same in the future. With more warming, the prevalence in West Africa will decrease. In other subregions, whether it increases or decreases will depend on the extent of warming. But overall, the authors expect a decline in malaria prevalence in Africa due to climate change, with an increase in certain areas that have not experienced the disease for a long time. What’s most uncertain about these projections is the impact of extreme weather events. When these are modeled, some project an increase in malaria cases and deaths, due to the shocks on healthcare and malaria control systems. Read Hannah’s article 📈 DATA INSIGHTS Bite-sized insights on the world and how it's changing Since our last OWID Brief, we’ve published insights across various topics: Child mortality has declined in all world regions → Europe is older, but Latin America is aging faster → What share of plastic waste ends up in the ocean? → Electricity generation per person in the United Kingdom has fallen by a third from its early-2000s peak → The new Living Planet Index reports a 73% average decline in studied wi