Final answer:
The end of the ahu and mo'ai building period on Rapa Nui coincided with the deforestation of the palm forest around 1600, which is true. This environmental degradation contributed to the society's collapse.
Step-by-step explanation:
The end of the mo'ai and ahu building period on Easter Island, also known as Rapa Nui, is often associated with environmental degradation on the island, particularly the deforestation of the palm forest. Historical studies and archaeological evidence suggest that the native people of Rapa Nui faced significant challenges due to the overexploitation of natural resources, which led to difficulties in sustaining their culture and the collapse of their society. The lack of wood for constructing boats meant they were isolated on the island, which coupled with external pressures such as European invasions and introduced diseases, led to the decline of their society. Hence, the statement that the end of the ahu and mo'ai building period roughly coincided with the complete destruction of the palm forest around 1600 is True.