Under conditions of famine, human beings commonly resort to cannibalism.
Examples from Ancient History
Large amounts of "butchered human" bones found in Paleolithic sites indicate that cannibalism was common in these societies. Famine is the likely cause, as bones at the site indicate malnourishement. 
German researchers have documented 1,891 signs of cannibalism in the caves at the Hönne (1000 - 700 BC).  Extensive evidence of Iron Age (about 2000 years ago) cannibalism has likewise been found in Great Britain.
Cannibalism is mentioned many times in early history and literature as a recourse during famine, e.g., in the Bible (2 Kings 6:25–30) during the siege of Samaria. Flavius Josephus reported cannibalism during Roman sieges of Numantia in the second century BC and Jerusalem in 70 AD.
Easter Island inhabitants were reduced to cannibalism after total deforestation left them without building material or means for husbandry, e.g., without trees and wood, it was very difficult to avoid soil erosion, which made agriculture extremely tenuous. 
Other pacific islands that may have suffered similar fates include New Zealand , the Solomon Islands , Fiji, New Guinea , Polynesia and Sumatra . Conclusive evidence of cannibalism has also been found among the Anasazi , another society which suffered environmental collapse. 
Examples from Recent History
Credible reports of modern cannibalism include:
- Jamestown colonists during "the Starving Time" from 1609–1610. After food supplies were exhausted, colonists dug up corpses for food. One colonist confessed to having killed, salted, and eaten his pregnant wife. 
- Survivors of the Luxborough Galley in 1727 during their two weeks on a small boat in the mid-atlantic.
- The Donner Party while snowbound in the mountains for the winter of 1846–47.
- The last survivors of Sir John Franklin's 1848 expedition in their final push across King William Island, Canada.
- Survivors of the ship Dumaru after it exploded and sank during World War I [Lowell Thomas, The Wreck of the Dumaru (1930)]
- Ukrainians during a famine in the 1930s and Soviets during the World War II Siege of Leningrad 
- Chinese during their Civil War (1945-49), Great Famine (1958-61) and following the "Great Leap Forward".
- Prisoners in World War II Nazi concentration camps 
- Japanese troops during World War II 
- North Koreans during a famine between 1995 and 1997.
- Survivors of a Uruguayan flight consisting of a college rugby team and some of their family members, while trapped at the crash site. The flight crashed on 13 October 1972 but because of severe weather rescue operations did not begin until 22 December 1972. 
update sff 01-25
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