Africa is the second largest continent on planet Earth. Including adjacent islands Africa spans over 30 million kmē which accounts for about 20% of the total land area on the planet. Africa is also the second most populated continent. Over 1 billion people called Africa "home" in 2009.
Seasonal Affective Disorder is more rare in Africa since it is the hottest continent and much of it is covered in arid desert or savanna plains. Although, the continent does have a huge diversity of climates including tropical rain forests and sub-arctic peaks.