Animal Adaptation to Climate Change: Looking Through the Lens of the Quino Checkerspot Butterfly

Climate change affects animals. This is not a new revelation. The first IPCC Assessment Report, released in 1990, discusses how climate change negatively impacts polar bears. But the conversation on animals and climate change often neglects the stories of how animals survive by adapting to climate changed conditions.

Many species adapt by broadening their diets and changing other behaviors, such as migrating patterns, mating habits, and hibernation lengths. For example, the National Wildlife Federation reports that the Quino checkerspot butterfly was disappearing in the late 1990’s. The butterfly was dying because hot weather in California was causing its host plant to dry out before any caterpillars could enter adulthood.

This endangered subspecies was considered a “goner,” but then the Quino did something surprising. Surrounded by desert, the butterfly could not migrate butterflynorth to wetter terrain. Instead, it moved to higher ground. The Quino population resettled at a higher elevation and most importantly, adapted to using a new host plant. This adaptation is exciting because it indicates what one scientist calls “a genetic revolution.”

Moving to a new host plant isn’t as easy as it sounds. The butterfly genes governing its search image and its natural instinct to lay eggs on a particular plant have to change. This one genetic change can create a domino effect on the genetic make-up of the Quino. For instance, the butterfly might have to alter the number of eggs it lays because of the new host plant’s capacity to nourish young caterpillars. In turn, the young caterpillars might need to develop new enzymes in order to eat the new host plant.

If the decision to move to a higher elevation is able to change what type of enzymes the next generation of Quino produces, the capacity for animal adaptation to climate change is immense. This past summer, researchers discovered polar bears have started eating dolphins. As northern seas become ice free, dolphins are migrating farther north, which in turn provides starving polar bears a new source of food.

Animal adaptation to climate change will not stop global warming, but it does illustrate why the UNFCCC is making an effort to enable the human animal to adjust to a climate-changed world. In order to mitigate climate change, humans must be able to adapt to the changes already occurring. The new agreement draft text shows that Parties are trying to balance mitigation and adaptation efforts in their commitments to address climate change concerns.