This idea that Rapa Nui society collapsed came out of the imbalance between general resources present on the island, mainly population, timber and food sources, and the energy- and resource-intensive feat of transporting and raising the moai. Food resources may have been scarcer than in other areas of Polynesia because of factors like the cooler climate, lack of rainfall in comparison to other islands in the area, high winds and a lack of biodiversity, leading to common Polynesian crops not faring as well as they would in other areas of the Pacific. A source of good timber is also currently noticeably absent from the Island, the tallest, extant plant life averaging around 7 feet.