As climate changes, many species are moving. Sometimes, it is from lower to higher altitudes, in order to live in familiar temperatures. Sometimes, it is from south to north for the same reason. Such natural adaptation is inevitable and, while it is a coping mechanism for individual species, it invariably changes the composition of ecosystem. Birds and flying insects may be able to relocate more easily, leaving slower-moving or less adaptable species behind. Suddenly, the structure of food webs start to change as predator-prey relations are redefined.
Some people have argued that allowing ecosystems to respond to climate change on their own is the best course of action. Others have argued that vulnerable species should be relocated to areas where they will be able to continue living. Some have even argued that polar bears should be relocated to Antarctica to make them less vulnerable to global warming. Others have argued that elephants and rhinos should be introduced to North America as a hedge against the danger of poaching. Finally, there are those who argue that we should actively manage ecosystems to try to mitigate climate change effects: if pests have shifted into new areas and begun eating crops, import their predators. If coastal erosion is worsening, bring in species to stabilize beaches.
The human record of such interventions is definitely not stellar, but the debate is nonetheless increasingly energetic. The discussion is both pragmatic – asking what the probable costs and benefits of making a change would be – and philosophical – engaging with the question of what the ‘natural’ world is and how people should engage with it. Global climatic change will make both of these sets of questions more immediately relevant and pressing.
