Editorial: Mammoth de-extinction is bad conservation

Summary

The evidence for how living elephants affect carbon sequestration is also quite mixed. On the one hand, one paper finds that African forest elephants knock down softwood trees, making way for hardwood trees that sequester more carbon. But on the other hand, many more researchers looking at African savannas have found that elephants knock down lots of trees, converting forests into savannas and reducing carbon sequestration. Colossal’s website offers links to peer-reviewed research that support their suppositions on the ecological role of woolly mammoths. A key study offers intriguing evidence that keeping large herbivores—reindeer, Yakutian horses, moose, musk ox, European bison, yaks, and cold-adapted sheep—at artificially high levels in a tussock grassland helped achieve colder ground temperatures, ostensibly protecting permafrost. But the study raises lots of questions: is it possible to boost these herbivores’ populations across the whole northern latitudes? If so, why do we need mammoths at all—why not just use species that already exist, which would surely be cheaper? Plus, as ecologist Michelle Mack noted, as the winters warm due to climate change, too much trampling or sweeping away of snow could have the opposite effect, helping warm the soils underneath more quickly—if so, mammoths could be worse for the climate, not better. All this is to say that ecosystems are diverse and messy, and those of us working in functional ecology don’t always discover consistent patterns. Researchers in the field often struggle to find robust evidence for how a living species affects modern-day ecosystems—surely it is far harder to understand how a creature extinct for around 10,000 years shaped its environment? And harder still to predict how it would shape tomorrow’s ecosystems? In effect, Colossal’s ecological narrative relies on that difficulty. But just because claims about the distant past are harder to fact-check doesn’t mean they are more likely to be true.