This is a story about bad timing.

One of the most disturbing ways that climate change is already playing out is through what ecologists call “mismatch” or “mistiming.” This is the process whereby warming causes animals to fall out of step with a critical food source, particularly at breeding times, when a failure to find enough food can lead to rapid population losses.

The migration patterns of many songbird species, for instance, have evolved over millennia so that eggs hatch precisely when food sources such as caterpillars are at their most abundant, providing parents with ample nourishment for their hungry young. But because spring now often arrives early, the caterpillars are hatching earlier too, which means that in some areas they are less plentiful when the chicks hatch, with a number of possible long-term impacts on survival.

Similarly, in West Greenland, caribou are arriving at their calving grounds only to find themselves out of sync with the forage plants they have relied on for thousands of years, now growing earlier thanks to rising temperatures. That is leaving female caribou with less energy for lactation, reproduction and feeding their young, a mismatch that has been linked to sharp decreases in calf births and survival […]