The female pigeon cannot lay eggs if she is alone. In order for her ovaries to function, she must be able to see another pigeon. See more

Yemen, a quasi-failed state torn by civil war, had 54.8 guns per 100 people in 2007. See more

Acorns were used as a coffee substitute during the American Civil War. See more

The shortest war in history was between Zanzibar and England in 1896. Zanzibar surrendered after 38 minutes. See more

The cockroach has a high resistance to radiation and is the creature most likely to survive a nuclear war. See more