Richard Weber, an expert on airborne allergens at the National Jewish Medical and Research Centre in Denver, Colorado, notes that new homeowners insist on planting and watering foreign vegetation.

ECONOMIST: With drought and pollution, Arizona is full of sneezers

It helps that the sort of people who do not have landlines are also the sort who tend to turn out in relatively low numbers in mid-term elections, notes Scott Keeter of the Pew Centre.

ECONOMIST: Political polls

Dr. Daniel Ramp at the University of Technology, Sydney (Australia), where a centre for Compassionate Conservation is being established, notes, by placing compassion alongside conservation, decision-making that results in poor animal welfare and conservation outcomes should become more transparent and avoidable and this will be a great aid to wildlife management.

FORBES: Compassionate Conservation: A Discussion from the Frontlines With Dr. Marc Bekoff

Gunnar Myhre of the Centre for International Climate and Environmental Research in Oslo, for example, notes that the amount of black carbon in the Arctic is small and has been falling in recent decades.

ECONOMIST: Climate change in the Arctic