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Biofuels and the Lessons of Easter Island  [PDF]
Antonio R. Chaves
Sustainability , 2009, DOI: 10.3390/su1030335
Abstract: The return to land-based biofuels ignores the lessons of the past that led to the collapse of civilizations such as that of Easter Island. Even the more efficient ethanol feedstocks such as sugar cane and switchgrass can greatly worsen the environmental damage associated with agriculture because they would require enormous amounts of land to meet US demand for transportation fuel. Too often, style wins over substance because most citizens do not know the basics of well-to-wheel analysis. Therefore, the incorporation of energy literacy into the high school curricula should play a significant role in any comprehensive plan for addressing the energy crisis.
Mathematical Model of Easter Island Society Collapse  [PDF]
M. Bologna,J. C. Flores
Quantitative Biology , 2010, DOI: 10.1209/0295-5075/81/48006
Abstract: In this paper we consider a mathematical model for the evolution and collapse of the Easter Island society, starting from the fifth century until the last period of the society collapse (fifteen century). Based on historical reports, the available primary sources consisted almost exclusively on the trees. We describe the inhabitants and the resources as an isolated system and both considered as dynamic variables. A mathematical analysis about why the structure of the Easter Island community collapse is performed. In particular, we analyze the critical values of the fundamental parameters driving the interaction humans-environment and consequently leading to the collapse. The technological parameter, quantifying the exploitation of the resources, is calculated and applied to the case of other extinguished civilization (Cop\'an Maya) confirming, with a sufficiently precise estimation, the consistency of the adopted model.
Herrera González,Víctor Fernando;
Ingeniare. Revista chilena de ingeniería , 2007, DOI: 10.4067/S0718-33052007000200010
Abstract: this project resorts al use integrated and satellite images application with high spatial resolution (quickbirdii). the purpose of this project is to demonstrate the contribution of geomatics technologies for cadastral applications in easter island (chile). this project resorts use integrating satellite images with high spatial resolution (quickbridii), gps equipment and geographic information system (gis) in a very particular zone in land use administration like rapa nui or easter island . the result obtained with high accuracy measurements, resolved the geo reference for the land use map of the city and also defined the geometric control point for the satellite image correction process. finally, with the creation of this cartographic data base we can mix the information with the cartographic mosaic necessary for the ministry of national assets . the data gathered with this technique is very important for the government actions regarding future transference of land to the descendants of ancient inhabitants of the island. also, there is special relevance in the application of geomatics technologies in the island, when it comes to improve the urban growth planning and people's life conditions.
Ecological Release and Venom Evolution of a Predatory Marine Snail at Easter Island  [PDF]
Thomas F. Duda, Taehwan Lee
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0005558
Abstract: Background Ecological release is coupled with adaptive radiation and ecological diversification yet little is known about the molecular basis of phenotypic changes associated with this phenomenon. The venomous, predatory marine gastropod Conus miliaris has undergone ecological release and exhibits increased dietary breadth at Easter Island. Methodology/Principal Findings We examined the extent of genetic differentiation of two genes expressed in the venom of C. miliaris among samples from Easter Island, American Samoa and Guam. The population from Easter Island exhibits unique frequencies of alleles that encode distinct peptides at both loci. Levels of divergence at these loci exceed observed levels of divergence observed at a mitochondrial gene region at Easter Island. Conclusions/Significance Patterns of genetic variation at two genes expressed in the venom of this C. miliaris suggest that selection has operated at these genes and contributed to the divergence of venom composition at Easter Island. These results show that ecological release is associated with strong selection pressures that promote the evolution of new phenotypes.
Easter Island: the Tongariki and Mataveri Solar Observatories Used a Common Methodology  [PDF]
Sergei Rjabchikov
Physics , 2015,
Abstract: Two additional positions of the famous Mataveri calendar of Easter Island have been interpreted. The information about the stars of the Virgo constellation has been obtained, too. As a result, the archaic Rapanui name of the star Spica and the Hawaiian name of this star have been compared.
Challenging Easter Island's collapse: the need for interdisciplinary synergies  [PDF]
Valentí Rull,Núria Ca?ellas-Boltà,Alberto Sáez,Olga Margalef,Roberto Bao,Sergi Pla-Rabes,Blas Valero-Garcés,Santiago Giralt
Frontiers in Ecology and Evolution , 2013, DOI: 10.3389/fevo.2013.00003
Abstract: The reigning paradigm holds that Easter Island suffered a socio-ecological collapse (ecocidal or not) sometime in the last millennium, prior to European contact (AD 1720). We discuss some novel paleoecological and archaeological evidence that challenges this assumption. We use this case study to propose a closer collaboration between archaeology and paleoecology. This collaboration allows us to unravel historical trends in which both environmental changes and human activities might have acted, alone or coupled, as drivers of ecological and social transformations. We highlight a number of particular points in which scholars from disparate disciplines, working together, may enhance the scope and the soundness of historical inferences. These points are the following: (1) the timing of the initial Easter Island colonization and the origin of the settlers, (2) the pace of ecological and social transformations since that time until the present, and (3) the occurrence of potential climate-human synergies as drivers of socio-ecological shifts.
The Astronomical and Ethnological Components of the Cult of Bird-Man on Easter Island  [PDF]
Sergei Rjabchikov
Physics , 2013,
Abstract: The bird-man cult remains the main secret of Easter Island (Rapa Nui), a remote plot of land in the Pacific. This paper includes not only necessary ethnological data, but also some results on the archaeoastronomy. The research of some lines marked on a stone calendar from the Mataveri area, an archaic zone of the bird-man cult, allows to insist that the natives watched at least the stars Canopus and Aldebaran. There are strong grounds for believing that, among others, the Sun, the Moon as well as Beta and Alpha Centauri were the matter for quasi-scientific enquiry. Several astronomical and calendar records in the rock art and in the script have been decoded.
Eufáusidos de Isla de Pascua Euphausiids of Easter Island  [cached]
Oscar Robledo B.,Armando Mujica R.
Investigaciones Marinas , 1999,
Abstract: Se analiza la distribución espacial y abundancia relativa del Orden Euphausiacea en aguas circundantes a Isla de Pascua en mayo de 1994. Las muestras zooplanctónicas se obtuvieron en 16 estaciones oceanográficas mediante pescas oblicuas efectuadas con redes Bongo de 330 μ, entre la superficie y 250 m de profundidad. Se analiza la estructura comunitaria de los eufáusidos, mediante índices de constancia y dominancia. En todas las estaciones se registró la presencia de eufáusidos, encontrándose las mayores diversidades en las estaciones más alejadas de la isla. Stylocheiron suhmii y S. affine fueron las especies más abundantes y frecuentes. La posible influencia que pudiese tener la isla y las condiciones oceanográficas en la agregación de organismos zooplanctónicos, no pudo ser detectada en la distribución y abundancia de las especies de eufáusidos, debido principalmente a la escala espacial del muestreo. Se sugiere que el comportamiento y migración vertical de las especies, puede ser un factor determinante en la estructura comunitaria de los eufáusidos en torno a este ecosistema insular The spatial distribution and relative abundance of Euphausiacea, during May 1994, in waters around Easter Island, are analyzed. Zooplankton was sampled at 16 oceanographic stations. Double oblique sampling was done with Bongo net between the surface and 250 m depth. The community structure of euphausiids was analyzed using constancy and dominance. Euphausiids were present at all stations, and its diversity was most high in the most oceanic stations. Considering the numeric constancy and dominance the most important species were Stylocheiron affine and S. suhmii. The island presence and oceanographic influence in spatial distribution and relative abundance patterns of euphausiids around island don't was detected. It was associated to sampling scale. Probably the spatial distribution and relative abundance of euphausiids is related principally to behavior and vertical migration
Prevalencia de malformaciones congénitas al nacer y factores asociados en Isla de Pascua, Chile (1988-1998) Prevalence of congenital malformations at birth and associated factors in Easter Island, Chile  [cached]
Alfredo Aguila R,Julio Nazer H,Lucía Cifuentes O,Paola Mella A
Revista médica de Chile , 2000,
Abstract: Background: Consanguinity plays an important role in the genetic etiology of congenital malformations. In Easter Island the degree of consanguinity could be higher than in continental Chile. Therefore the study of the prevalence of congenital malformations in this island seems worthwhile. Aim: To study the prevalence of congenital malformations at birth in Easter Island. Material and methods: A review of personal and family features of all children born alive between 1988 and 1998 in the Rapa Nui Hospital of Easter Island. Results: During the study period, 772 newborns were reviewed and 22 were found to have congenital malformations. Among the latter, birth weight fluctuated between 3001 and 4000 g and the male/female ratio was 0.54. No differences in maternal age between children with and without malformations was observed. Heart and circulatory malformations, hemangiomas and Down syndrome were the predominant malformations. Conclusions: The prevalence of congenital malformations at birth in Easter Island is similar to that of continental Chile. No neural tube defects were detected in this sample.
Comment to Rull et al. (2013) – Challenging Easter Island’s Collapse: the need for interdisciplinary synergies  [PDF]
Annegret Larsen,Dale F. Simpson
Frontiers in Ecology and Evolution , 2014, DOI: 10.3389/fevo.2014.00056
Abstract: The road to deforestation and its social feedback on Rapa Nui is a fascinating and a possibly important parable; one with symbolic implications for how the rest of the world views environmental change and human impact. Rull et al. (2013) present a compilation and critique of Rapa Nui’s palaeoecological and archaeological data that is critical for progressing further work on the island, and state that Rapa Nui was subject of a gradual environmental change instead of rapid deforestation. The authors interpret the slower pace of deforestation as evidence for gradual social change, supported by Mulrooney’s (2013) recent archaeological investigation in La Pérouse Bay (Figure 1), therefore contradicting the hypothesis of an abrupt ecocidal collapse of Easter Island’s prehistoric society (Diamond, 1994). In order to advance their interpretations, the authors suggest a closer collaboration between archaeology and palaeoecology and propose a research agenda. It is important to understand that past environmental change provides limited conclusions in regards to societal change, as societies have the ability to adapt. However, palaeoecological information derived from the island’s lake records (Rano Aroi, Rano Raraku, and Rano Kau; Figure 1) is well established and used as the main evidence to support the island’s proposed collapse (Bahn and Flenley, 1992, Diamond, 2005). But, the limitations of palynological interpretation are well known and widely discussed in the scientific community (Blarquez et al., 2013, Flenley et al., 1991, Hunter-Anderson, 1998, Ritchie, 1995). Thus, a call for closer collaboration between archaeology and palaeoecology is somewhat surprising. Instead, we suggest that a widening of disciplines in order to use a varied range of interpretive techniques, and a multiplicity of environmental and archaeological archives, would be of much greater advantage in order to understand the heavily discussed past of Rapa Nui (F?rster et al., 2013). Rull et al. (2013) set up a research agenda which presumes common questions between archaeology and palaeoecology based on a summary of previous work. However, this summary seemed to be focused on selected archaeological publications, and furthermore dismissed palaeoecological data from archives other than lake records. As a result, the authors: 1. Point out that there is new evidence for a gradual deforestation of the island, instead of abrupt ecological change. To our knowledge however, the majority of scientists have not actually proposed rapid deforestation, but for the process lasting ~400 of years or
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