They have lots of water and were often used as a source of water in dry areas. Rind used to make pickles. Orientals preserve in salt. Canteloupes and honey dew etc. The wild ancestors of these are unknown.
Cucumbers are native to southern Asia.
Has long been cultivated in both. Probably drifted across Atlantic from Africa to S. America. The bottle gourd is not only used as a food plant, but is probably most important as a container plant. Luffa, momordica are minor cucurbit crops. This fruit plant is native to Peru or Mexico.