Prior to human settlement, Rapa Nui was controlled by big palm trees of a range now extinct; nevertheless, they were connected to the Chilean red wine palm (Jubaea chilensis.

These enormous trees can measure up to 500 years; they’re likewise slow-growing, taking around 70 years to reach maturity and start to fruit.

Few of the palms stayed at the time of European contact in 1722. By the time the Europeans started to take an interest in the island’s ecology, they were gone.

“The Europeans essentially explain a treeless island, however they likewise explain palms and palm leaves,” stated Binghamton University’s Professor Carl Lipo.

“It’s difficult to understand whether they’re utilizing the term to explain some other tree.”

When setting out for a brand-new island, the Polynesian individuals brought their subsistence plan with them: taro, sweet potatoes, bananas, yams, pet dogs, chickens and pigs. Accompanying was, undoubtedly, the Polynesian rat.

Unlike the Norway rats (Rattus norvegicusgiven the island after European contact, this little, arboreal types chooses to reside in the tree canopy. For scientists, the rats are a goldmine of details.

“Because of their genes and the ‘creator’s impact,’ they have special haplotypes,” Professor Lipo stated.

“We can trace the colonization of individuals and, to some degree, the variety of colonizations by how variable the rats are as they cross the Pacific.”

Precisely how they wound up in Polynesian’ outrigger canoes refers argument: Were they stowaways or brought intentionally as a backup food source? Ethnographic proof recommends the latter.

“After the arrival of Europeans, a biologist gathering specimens for the British Museum saw a male strolling down a course, bring rats; he informed the collector that they were for lunch,” Professor Lipo stated.

Rat bones are likewise discovered in midden deposits– basically, ancient garbage loads– throughout the Pacific islands.

When the Polynesians got here on Rapa Nui around 1200 CE, the rats discovered a virtual Eden without predators and loaded with their preferred food.

Efficient in having numerous litters a year, the population took off into the millions in a couple of years’ time.

“Palm nuts are rat sweet. The rats went bananas,” Professor Lipo stated.

Rapa Nui’s palm trees co-evolved with birds and never ever established the boom-and-bust efficiency cycle that would make sure some nuts made it through exploitation by rodents.

The rats feasted on the palm nuts, avoiding the next generation of trees from settling.

The people cut down swathes of trees to develop their sweet potato fields. The mix of the 2 resulted in the logging that marks the island today.

In addition to plants and animals, the Polynesian survival package likewise consisted of practices such as slash-and-burn farming to increase soil fertility.

Older volcanic islands such as Rapa Nui can experience bad soils, the nutrients seeped out by the rain.

Cleaning and burning areas of forested land can momentarily instill the soil with nutrients.

When the nutrients wear, the farmers relocate to another website, leaving the land to recuperate and the trees to grow back.

“We see this in New Guinea and other locations throughout the Pacific,” Professor Lipo stated.

“But on Rapa Nui, the trees grow so gradually, and they do not grow back due to rat predation on the palm nuts.”

Eventually, the islanders turned to a brand-new design of farming, utilizing stone mulch to improve their crops.

While the loss of the palm forest was an indisputable ecological modification, it wasn’t a human catastrophe.

The islanders didn’t require the palm trees for survival; rather, their food sources depended upon cleared land.

In addition, palms aren’t hardwood trees; they’re connected to yards, and can not supply wood for canoes, homes or fire wood.

“It’s an unfortunate loss of a palm forest, however it wasn’t a catastrophe for individuals,” Professor Lipo stated.

“It wasn’t a needed part of their survival.”

While a few of the palm trees might have endured into the European profession, the intro of sheep ranching in the 19th century might have sounded the last knell of termination; any staying seedlings would have been consumed by the sheep.

Paradoxically, the Polynesian rats satisfied the exact same fate as the palms; on a lot of islands, they were driven to termination, out-competed by the Norway rat, or taken in by presented predators such as hawks.

While the particular types has actually altered, islanders still inform stories of rodent boom and bust cycles– years when the population takes off, followed by an enormous die-off.

The story of Rapa Nui is among unintentional repercussions– however likewise of adjustment and survival on among the world’s most remote occupied islands, where the closest next-door neighbors are 1,931 km (1,200 miles) away.

“We need to be more nuanced in our understanding of ecological modification,” Professor Lipo stated.

“We belong to the natural world; we improve it frequently for our advantage, however that does not always indicate that we develop an unsustainable world for ourselves.”

The findings appear in the Journal of Archaeological Science

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Terry L. Hunt & & Carl P. Lipo. 2025. Reassessing the function of Polynesian rats (Rattus exulansin Rapa Nui (Easter Island) logging: Faunal proof and eco-friendly modeling. Journal of Archaeological Science 184: 106388; doi: 10.1016/ j.jas.2025.106388