How migration makes life more resilient
The silver Y moth migrates between southern and northern Europe every spring. David Tipling/Universal Images Group via Getty Images Excerpted from The Jewel Box: How Moths Illuminate Nature’s Hidden Rules by Tim Blackburn. Copyright © 2023. Published by Island Press. The composition and structure of ecological communities doesn’t only depend on what happens in their immediate vicinity. Events in the wider environment are important, too. All of nature is connected. This is why migration matters. Indeed, migrants have never mattered so much. Humanity has destroyed a substantial proportion of natural habitat worldwide, and much of what is left is now heavily fragmented—small islands in a sea of inhospitable cropland, pasture, or concrete. The populations they house will be small, too, and susceptible to the vagaries of badluck. Luckily, as we’ve seen, fragmented populations can still persist...