I believe, I was taught this theory in school too and my parents told me about it.
"The history of Easter Island has long served as an environmental fable.
"The popular “ecocide” theory claims that, during their escalating obsession with building the famous Moai statues, the native Rapa Nui people deforested their once-verdant island, creating an ecological crisis that led to population collapse, cannibalism, and a complete reordering of Rapa Nui society.
A new study raises serious doubts about this narrative. After analyzing the remains of 15 ancient islanders, researchers found no evidence of the drop in genetic diversity one would expect after a population collapse. In fact, the genomes suggest Easter Island’s population grew steadily until European contact. According to archaeogeneticists Stephan Schiffels and Kathrin Nägele, “the study concludes that there were never more than 3,000 people living on Rapa Nui — a number close to that observed by the first colonizers and far from a previous estimate of 15,000 inhabitants — implying that the hypothesized collapse was always a fantasy.” ..."
From the abstract:
"Rapa Nui (also known as Easter Island) is one of the most isolated inhabited places in the world. It has captured the imagination of many owing to its archaeological record, which includes iconic megalithic statues called moai. Two prominent contentions have arisen from the extensive study of Rapa Nui.
First, the history of the Rapanui has been presented as a warning tale of resource overexploitation that would have culminated in a major population collapse—the ‘ecocide’ theory.
Second, the possibility of trans-Pacific voyages to the Americas pre-dating European contact is still debated.
Here, to address these questions, we reconstructed the genomic history of the Rapanui on the basis of 15 ancient Rapanui individuals that we radiocarbon dated (1670–1950 ce) and whole-genome sequenced (0.4–25.6×). We find that these individuals are Polynesian in origin and most closely related to present-day Rapanui, a finding that will contribute to repatriation efforts. Through effective population size reconstructions and extensive population genetics simulations, we reject a scenario involving a severe population bottleneck during the 1600s, as proposed by the ecocide theory. Furthermore, the ancient and present-day Rapanui carry similar proportions of Native American admixture (about 10%). Using a Bayesian approach integrating genetic and radiocarbon dates, we estimate that this admixture event occurred about 1250–1430 ce."
Ancient Rapanui genomes reveal resilience and pre-European contact with the Americas (open access)
Fig. 1: Shared drift and identity by descent between Ancient Rapanui and present-day populations.
Fig. 2: ROH and Rapanui population size estimates through time.
