In the 31 countries at the bottom of the list, 28 of which are in sub-Saharan Africa, a person can hope to live on average only 46 years, or 32 years less than the average life expectancy in countries of advanced human development, with 20 years slashed off life expectancy due to HIV/AIDS.
Ice wedges are a big cause of potholes in roads and streets. As ice forms in the cracks of a street, the water expands and pushes against the surrounding rock, making the cracks wider, eventually breaking apart the rock.
