how d'you like those apples...?
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In Spring 2000 world population estimates reached 6 billion; that is 6 thousand million. The distribution of the earth's population is shown in this map.
The Brain The human brain is the most complex and least understood part of the human anatomy.
This list defines 633 sciences, arts and studies of various degrees of respectability and rarity, ranging from the common and esteemed (chemistry) to the obscure and quirky (peristerophily).