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Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

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Page 1: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui)(CELF Institute)

Page 2: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Do Now:

How has our environment influenced our culture?

Page 3: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Easter Island

Page 4: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Location, Location, Location Chile lies 2,300 miles to the east and Tahiti 2,500 miles to the

northwest.

The nearest island, with a total population of 54 people, is tiny Pitcairn island, 1,400 miles to the west. Easter Island is approximately 60 square miles.

Its subtropical location, latitude-at 27S support a mild climate, and its volcanic origins make its soil fertile.

In theory, this combination of blessings should have made Easter a miniature paradise, remote from problems that beset the rest of the world.

Page 5: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Most Widely Accepted History “In the fifth century CE, the island was reached by no more than twenty or thirty Polynesians. The population slowly grew as agriculture developed on the island. Many native Polynesian food sources could not be propagated on the island. Sweet potatoes and chickens were successfully raised. The islanders were heavily dependent on fishing, which they did in wooden canoes.

16 C the population peaked at around 7,000 – 10,000 people. Initially, the agriculture was successful enough so as to only require a relatively small amount of labor, leaving the inhabitants with large amounts of free time that enabled them to develop complex religious ceremonies and rituals.”

In 1877, 110 inhabitants remained, the rest having been taken into slavery by European explorers.

Clive Ponting (1991)

Jared Diamond (2005)

Page 6: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

The Mystery of the Stone Giants •There are 887 stone busts (Moai) located

throughout the island.

•Their function is not understood. They are believed to have been used in religious ceremonies and also as signs of prestige among the different clans on the island.

•Moai are visible in many positions. Some face out to the sea, others face inland “to watch and protect the villages.”

•Many are toppled, and others await release from the sides of the cone at Rano Raraka, birthplace of the Moai.

Page 7: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Ancient Monoliths

Rano Raraku’s slopes are filled with several hundred eye-less Moai in various states of construction.

Half buried Moai on the sides of the volcanic cone of Rano Raraku are pieces still waiting to be transported to ahu (platforms) around the island.

Moai sticking out of the ground have bodies that extend underground 20 - 40 feet, to the waist.

Centuries of erosion from slopes above cover all but the tops of these giants.

Moai (Ahu Tahai), restored by William Mulloy

Page 8: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Map of Easter Island Showing Locations of Moai

Page 9: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Number and Distribution of Moai Total number of Moai that were successfully transported to their

final ahu locations: 288 (32% of 887)

Total number of Moai still in the Rano Raraku quarry: 397 (45%)

Total number of Moai lying ‘in transit’ outside of the Rano Raraku quarry: 92 (10%)

Why? Was this due to the inherent difficulties in transporting them? Were the ones that remain in the quarry (45%) deemed culturally

unworthy of transport? Were they originally intended to remain in place on the quarry

slopes? Had the islanders run out of the resources necessary to complete

the Herculean task of carving and moving the Moai?

(PBS,2007)

Page 10: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Excavation and RestorationAhu Tongariki, excavated and restored (1995) by archaeologists Claudio Cristino and Patricia Vargas.

“Final results of this on-going research project and full presentation of the archaeological data, chronology and conservation and reconstruction procedures of the site await completion. Most of the preliminary conclusions presented, regarding the character and archaeological evolution of the monument, should be considered with reservation, although we think that they will not significantly change after the data analysis of this profoundly disturbed site are completed.”

Page 11: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

How could such a people create, and then move such enormous structures? The answer lies in Easter islands’ ecological past, when the

island was not a barren place.

Dutch recorded that the Moai “walked” suggesting that they were transported in an upright position.

Easter Island society built the famous statues and hauled them around the island using wooden platforms and rope constructed from the forest. The construction of these statues peaked from 1200 to 1500 AD, probably when the civilization was at its greatest level.

Pollen analysis shows that at this time the tree population of the island was rapidly declining as deforestation took its toll.

Page 12: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

How Were the Moai Transported? In Dutch illustrations, the statue is on a base of

some sort. Workers are in the process of doing something underneath the base while others appear to pull.

American Geologist Charles Love, in a series of experiments, successfully moved a replica Moai by placing it on two logs cut to fit into the bottom of the statue. When raised onto a track of wooden rollers he found that his 10 ton Moai could be moved 145 feet in just a few minutes using 25 men and two ropes.

Page 13: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Theories of Moai Transport

NOVA on-line

Page 14: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

The Relationship Between Culture and Environment The island environment contributed to the development of certain

cultural practices. Subsequently, culture had a massive effect on the environment.

The ease of farming permitted sufficient time to develop their culture. Available stone allowed for the massive quarrying, and the abundance of trees most likely prompted the people to transport these statues the way that they did.

Although the culture that developed on Easter Island was largely influenced by the ecosystem of the island, certain aspects of the society became increasingly incompatible with that ecosystem. It was the cultural practices of the islanders and their inability to change their ways that destroyed the resources (namely forests) that the society depended on, ultimately destroying the society of Easter Island.

Page 15: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Trees native to Easter Island were extremely slow growing (Ehrlich, 2000), what may have been a standard deforesting process for the early islanders in their previous homes could have been too much for Easter Island to support.

Most scholars point to the cultural drive to complete the colossal stone projects on Rapa Nui as the key cause of depletion of the island's resources.

Palm forests disappeared, cleared for agriculture and for moving Moai.

“The price they paid for the way they chose to articulate their spiritual and political ideas was an island world which came to be, in many ways, but a shadow of its former natural self.”

Page 16: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Ecology The Easter Island of ancient times supported a sub-tropical

forest including the tall Easter Island Palm, a tree suitable for building homes, canoes, and latticing necessary for the construction and transport of Moai.

The vegetation of the island, provided natives with fuel wood and the resources to make rope.

Sea-worthy canoes enabled Easter Islanders to live off a steady diet of porpoise.

A complex social structure developed complete with a centralized government and religious priests.

Page 17: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Deforestation Moai were transported over the island on systems giant wooden

transport structures. This practice was ultimately responsible for the almost complete deforestation of the island. (Ponting, 1991)

By 1600, deforestation had dried out and practically ruined the soil, making agriculture much less productive.

Islanders could no longer make boats for fishing, and more importantly, were essentially trapped on the island.

Evidence based on pollen analysis supports the theory that Easter Island inhabitants destroyed their own society through deforestation. (Diamond, 1995)

Page 18: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Impact of Deforestation on Society The quality of life for Islanders plummeted. Streams and drinking water supplies dried up. Crop yields declined as wind, rain, and sunlight

eroded topsoil. Fires became a luxury - no wood could be found on

the island, and grasses were used for fuel. Rope was no longer available to move the Moai and

they were abandoned. Islanders began to starve, lacking their access to

porpoise meat and having depleted the island of birds.

The orderly society disappeared - chaos and disarray prevailed.

Page 19: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

1722: Europeans Discover Easter Island Easter Island was a barren landscape with no trees over ten feet in

height. No animals besides rats inhabited the island and the natives lacked

sea-worthy boats.

In 1722, Dutch explorers found the 3,000 islanders “engaged in almost perpetual warfare and cannibalism to supplement the food supplies on the island.” Inhabitants were thin and emaciated and lived in a state of civil disorder. (Ponting, 1991)

No sign of the great civilization that once ruled the island other than the strange statues

Europeans were mystified by the presence of great stone statues, 33 feet tall and weighing 82 tons -abandoned statues-as tall as 65 feet and weighing up to 270 tons. These too fell victim as they were ultimately desecrated.

Page 20: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

What Causes Deforestation on Pacific Islands?Deforestation is more severe on: Dry islands than wet islands; Cold high-latitude islands than warm equatorial

islands; Old volcanic islands than new volcanic islands; Islands without aerial ash fallout than islands with; Islands far from Central Asia’s dust plume than

islands near it; Low islands than high islands; Remote islands than islands with near neighbors;

and Small islands than big islands. (Diamond, 2005.)

Page 21: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Extinction 1400, Easter Island palm extinct due to over harvesting. Reproduction

severely limited by the proliferation of rats, introduced by the islanders when they first arrived, which ate its seeds.

Trees native to Easter Island were extremely slow growing (Ehrlich, 2000), what may have been a standard deforesting process for the early islanders in their previous homes could have been too much for Easter Island to support.

After the disappearance of the palm, ancient garbage piles reveal that porpoise bones declined sharply. The islanders, no longer with the palm wood needed for canoe building, could no longer make journeys out to sea.

The consumption of land birds, migratory birds, and mollusks increased. Soon land birds went extinct and migratory bird numbers were severely reduced –forests lost their animal pollinators and seed dispersers.

2007, only 1 of the original 22 species of seabird still nests on Easter Island.

Page 22: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Easter Island, Ancient Lorax?

How Life Works:

Many people simply do not understand a key scientific fact: that all life is predicated upon a host of unseen and therefore under-appreciated natural processes – the vital interactions produced by millions of years of evolution.

What are some of the processes/services provided by nature?

Page 23: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Easter Island as A Metaphor for the Modern World

Resource Depletion Isolation (no help to be found) No where to go Globalization (Easter Island’s clans)

Page 24: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Questions to Consider What are human-resource interaction and human impact on the

landscape?

Environment influences culture and culture influences the environment. How has our environment influenced our culture?

Throughout history there are many examples of human successes and failures of environmental manipulation. What are some examples for each?

What parallels do you see between the society of Easter Island and ours?

Why is Ester Island often referred to as a metaphor for our future?

Page 25: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

Easter Island as a Metaphor for Our Future? First inhabited more than 1000 years ago,

Easter Island, has become a showcase of the effects of human influences on the landscape.

With a population that peaked at over 10,000

people, the inhabitants quickly exceeded the island’s ecosystem, degrading the once-lush landscape and causing a collapse of the native civilization.

Page 26: Environmental Change and Sustainability: Lessons from Easter Island (Rapa Nui) (CELF Institute)

E. O. Wilson, Ph.D.“It is easy to overlook the services that ecosystems provide humanity. They enrich the soil and create the air we breathe. Without these amenities, the remaining tenure of the human race would be nasty and brief. The life-sustaining matrix is built of green plants with legions of microorganisms and mostly small, obscure animals. Such organisms support the world with efficiency because they are so diverse, allowing them to divide labor and swarm over every square meter of the earth’s surface. They run the world precisely as we would wish it to be run because our bodily functions are finely adjusted to the idiosyncratic environment already created.”