Lecciones de la adaptación por los Incas al último calentamiento global de la Edad Media
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Lecciones de la adaptación por los Incas al último calentamiento global de la Edad Media
- 1. Lecciones de la adaptación por los Incas al último calentamiento global de la edad media Alex Chepstow-Lusty (Universidad de Sussex e IFEA) Mick Frogley (Universidad de Sussex) Stef de Haan (CIP) Henry Juarez (CIP) Graham Thiele (CRP en Raíces, Tubérculos y Bananas - CIP)
- 2. Una conversación: papa y maíz! • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 30 años • Lecciones para el cambio climático
- 3. Contenido • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 30 años • Lecciones para el cambio climático
- 4. Sistema agrícola andino: integración vertical Maíz Llamas Papa
- 5. Contenido • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 30 años • Lecciones para el cambio climático
- 6. La expansión demográfica y el imperialismo incaico hubiera sideo posible solamente con los cultivos locales sin el maíz? Inca: complejo religioso-tecnológico adaptado a economía de tributo basado en maíz
- 7. Cuzco Contabilidad Almacenes de granos - Ollantaytambo Red de caminos Quipu Tecnología informática, caminera y de almancenamiento
- 8. Economía de tributo vs economía de afecto Guaman Poma, c. AD 1615
- 9. La papa: • Seguridad alimentaria - población local • 70% agua = 3x llamas/almacenes • Permitía tributo en maíz para elite urbano • Solidaridad en la economía de afecto: «papa de regalo» Llumchuy Waqachi – Lo que hacer llorar a la noera
- 10. Qué pasaban sin las llamas ni alpacas? Importantes para carne, textiles y transporte, vital para fertilidad
- 11. Contenido • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 30 años • Lecciones para el cambio climático
- 12. Lagunas (amarillo), X más pequeña = más sensible a la actividad humana
- 13. A LA SELVA CAPAC ÑAN 12 KM A OLLANTAY-TAMBO LAGO-RELLENADO DE MARCACOCHA, 3350 MASL PASTOREO VALORIZADO PATACANCHA RIVER Porqué Marcacocha?
- 14. * ? Registro de pólen en Marcacocha durante 4200 años (Chepstow-Lusty et al., 2003)
- 15. /Wari Aumento de aliso y el calentamiento global de la edad media Aliso - Alnus semilla y polen – usado para leña (Chepstow y Winfield, 2000)
- 16. * ? Registro de pólen en Marcacocha durante 4200 años (Chepstow-Lusty et al., 2003)
- 17. Acaros oribatidos ? ? (Chepstow-Lusty, 2011)
- 18. 1900 1800 1700 1600 1500 1400 * INCA AD AD 1300 1200 1100 1000 900 800 N-content (%) 0 1 2 3 0 20 40 60 80 Ä Ä 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 Post- Inca Inca Killke Wari Mites (cm-3) 5 4 3 2 1 20 40 C-content (%) N% C% * * ? Acaros oribatidos /cm3 (Chepstow-Lusty et al., 2007)
- 19. Acaros oribatidos: Nueva técnica para estimar la población de herbivores ? Marcacocha hoy: = ? = ? * Acaros imagenes de A. Baker, NHM. • Acaros oribatidos Bosta
- 20. Calentamiento global: expansión de maíz reconfiguración de papa • Cultivo de maíz expande en pisos altos • Construcción masiva de terrazas • Complejo tecnológico con maíz de grano largo, riego y bosta • Maíz: vinculado con pago de tributo • Papa: desplazado y aumenta en pisos mas altos • Papa: vinculada con seguridad alimentaria y economía de afecto
- 21. Ademas de terrazas y riego que papel tenia los sistemas agroforestales en la conservación de suelos? x
- 22. + Datos de M. Leng POR QUÉ MENOS FUEGO DURANTE IMPERIO INCAICO? ? Macrocarbón (> 125 microns/cm3) (Foto: ECOAN) Chepstow-Lusty et al.,en prep.) +
- 23. Contenido • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 50 años • Lecciones para el cambio climático
- 24. Comparando el glacier de Qoyllur Riti, cerca a Cuzco (c. 1930 y Abril 2009) c. 1930 por Martin Chambi April 2009 por Paolo Greer
- 25. Distribución de las papas nativas
- 26. Acercamiento: Distribución de las papas nativas
- 27. Altitud Promedia de Papas Nativas Nativas amargas Nativas harinosas 297m - 50 años 260m - 50 años
- 28. Efecto en rancha (tizón tardío) 60% de los gastos adicionales para controlar rancha con los productores de papas nativas sobre los 3,000 msnm Giraldo, D., Juarez, H., Pérez, W., Trebejo, I., Yzarra, W. and Forbes, G. (2010) Severity of potato late blight (Phytophthora infestans) in agricultural areas of Peru associated with climate change. Revista Peruana Geo-Atmosférica (2):56-67.
- 29. Efecto en polilla de la papa Modelo(ILCYM) basado en temperatura acoplado a SIG estima problema en 2050 27,506 ha adicionales en riesgo debido al cambio climático. Kroschel, J., Sporleder, M., Tonnang, H.E.Z., Juarez, H., Carhuapoma, P., Gonzales, J.C. and Simon, R. (2013) Predicting climate change caused changes in global temperature on potato tuber moth Phthorimaea operculella (Zeller) distribution and abundance using phenology modeling and GIS mapping. Agricultural and Forest Meteorology 170:228-241.
- 30. Cortando aliso (Alnus acuminata) por el rio Patacancha malo para el aliso – desproteje la ribera
- 31. Producción de leña y madera Foto ECOAN Guaman Poma, c. AD 1615 2007 Reliquio de chachacoma a 3700 m arriba del Valle Sagrado
- 32. Arboles nativos sobreviven protegidos alrededor a las casas (cerca a Huilloc, 1996)
- 33. Contenido • Sistema agrícola andino: integración vertical • El complejo religioso-técnico incaico • Calentamiento global de la edad media • Cambios en los últimos 30 años • Lecciones para el cambio climático
- 34. Selección participativa de papa en la Cuenca de Patacancha
- 35. Variedades liberadas con selección Liberadas: • 2007: Pallay Poncho (INIA 311) • 2007: Puka Lliclla (INIA 312) • 2010: Altiplano (INIA 317) • 2013: Kawsay (INIA 320) En carpeta: • 2014: Poderosa (La Libertad) • 2015: PAT-12 (Cusco) participativa
- 36. Puka lliclla: « manta roja que llevan las mujeres de Cuzco »: resistente a la rancha 10% área - Paucartambo
- 37. Choquebamba terrazas, valle de Patacancha P, cerca a Ollantaytambo, 6 km de canal Pumamarca Restoracion del sistema de abastecimiento (Cusichaca Trust, 1997) Restoración de canales de riego y terrazas en colaboracion con las comunidades locales y con enfoque holistico
- 38. Vacas comen hojas y arboles jovenes de f Polylepis, cerca a Queuñacocha, Huilloc. Controlar el acceso para regenerar el bosque
- 39. Otras formas para reducir el efecto de cambio climatico Ollantaytambo en el valle Patacancha x Huilloc Marcacocha X Pallata • Conservacion y expansión de bosque para proteger cuencas • Control de fuego Polylepis en Queuñacocha X Pequeño bosque de Unka (Myrcianthes oreophylla)
- 40. fin Y el futuro? Programas integrados de desarrollo, innovación y restauración
- 41. PÓLEN DE CIPERÁCEAS DEPOSITADO DURANTE PERIODOS SECOS
- 42. Porque la region de Cuzco es especial? x
- 43. Imperio incaico: crecimiento y caída Ollantaytambo Imperio incaico (AD 1400-1533)- predecible como la ultima etapa del desarrollo social pre-Colombino?
- 44. Dos imperios antes de los Inca: Tiwanaku c. AD 500-AD 1100 y Wari c. AD 600-AD 1000 PIKILLACTA Servicio Aerofotográfico Nacional, Peru. CUZCO * El éxito de los Incas depende del «colapso» de los Wari y Tiwanaku y tecnologia y conocimiento prestado?
- 45. La papa: Papa Maíz Productividad kg/ha (riego – 2400 masl) Productividad kcal/ha Kcal/kg Número de llamas para abastecer a Cuzco Número de hectáreas pasto natural
Hinweis der Redaktion
- We are going to look at the factors that contributed to producing the largest Empire in the New World, the Inca Empire (AD 1400-1533): In terms of technologies developed (or expanded), climate change and the « specialness » of the landscape in the heartland of the Cuzco area. However, fundamentally, we need to understand why food production (plus storage, distribution) could increase markedly and provide such surpluses to free up a large proportion of the population from agricultural activities, to undertake other specialized tasks, such as road building, building granaries, maintaining a large standing army, etc. To help understand these patterns we are going to focus on a palaeo-environmental record obtained from the small infilled lake (more of a « pond » that infilled about AD 1850) of Marcacocha (X), in the Patacancha Valley, 12 km north of the Inca settlement of Ollantaytambo, -the latter is where the Inca had their last battle (photo of the terraced fortress in a future picture) with the Spanish before retreating into the jungle. This valley is typical of many valleys north of the Sacred Valley-and we shall return to the site in detail later on.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …their amazing granaries (and technologies) for storing foods, and other products such as textiles and wood. Or their road systems, or even their quipus-most of which were destroyed by the Spanish, but some were transcribed in the Junin area, and reveal a system for counting a wide range of products, by a system of knots on different arrangements of cords. The granaries above Ollantaytambo, built on steep slopes, were very sophsticated and air would flow through them, while the produce remained dry inside-for potentially years. There are stories of the Spanish finding about ten years supply of food in the Inca granaries, showing how well stocked they were (even at a time of civil war, mobilizing two major forces against each other between the half brothers, Atahualpa-in the Quito area and Huascar in the Cuzco area, after the death of their father Huayna Capac). Certainly the supplies available show the efficiency of the Inca agricultural system, and perhaps the favorable climate at the time, but also the ability to store vast surpluses as an insurance against periods when the climate was not so optimal. And last but not least is..
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- And it must be remembered that crops such as maize (and potatoes to a lesser extent?) require lots of fertilizers, which have to be replenished. The Incas and their predecessors had only camelids as large domesticated animals. No horses, cattle, pigs, sheep, goats or chickens until the Spanish arrived. To what extent guano was brought from the coast is not known-as no clear archaeological evidence as such (yet). In terms of domesticated animals, they had abundant camelids (i. e. llamas and alpacas), who defecate communally, and it is an easy resource to be gathered. They had other smaller domestic animals, such as guinea pigs, dogs and ducks, but these were more of a minor food source. The abundant dung of camelids was (is) a vital resource in the Andes, not only as a fertilizer, but in this part of the world where trees are generally rare, dried dung can be used for cooking, heating, and even firing pottery. The camelids also provide meat and textiles and were used as beasts of burden. When considering warming during the Medieval Warm Period, and people expanding their agricultural zones to higher altitudes, fertilizers are still an important part of the equation. The Spanish chroniclers also record that human excrement was important as a fertilizer for maize in the Cuzco area. But not quite last it is worth considering…
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- Just to show a quick map of the area we are interested in, and the location of Marcacocha, 12 km northeast of Ollantaytambo. The flower symbols are major archaeological sites, but in this area, it is literally covered in archaeological sites. The blue line is the Sacred Valley, the red lines=the modern road network, and the hashed line, the railway network. The yellow boxes are lake sites/wetlands we have been investigating, but the focus has been Marcacocha (and the the Lucre Basin-but still yet to publish on this). You don’t really have to say much about this map. It is just to show the position of Marcacocha, and you may find you want to use it elsewhere.
- Why Marcacocha? Small and sensitive to surrounding landscape (« lake » only 35-40 m in diameter; in 1996, the infilled « lake » can be clearly identified by the concentration of brown sedges growing on top of it). For example, it mostly collects local pollen from the plants nearby, and the small organisms living in it are responding rapidly to the environment around it; an example as we shall see, are the oribatid mites which as detritivores are eating the broken down remains of large herbivore excrement which enters the lake, and comes from the animals using the concentrated pasture next to it (but we will talk about this later). Organic sediments have remained wet and well preserved for the last 4000 years (even during major arid intervals), as adjacent to the constantly flowing Patacancha River, from which water also infiltrates into the lake. It is so organic as a lot of terrestrial plant matter was also entering the « lake ». You have to imagine the circle of brown sedges as an open body of water before AD 1840. Located on major trading route and provides guaranteed pasture. The llamas would have come down to the pasture and defecated communally, creating an easily gatherable resource. Close to the boundary of maize and tuber production, and the upper limit for the only straight growing tree, the Andean alder, aliso. Surrounded by archaeological sites, so ideal for comparison with changes in human impact on the landscape over the last 4000 years. The photo is taken looking north up the Patacancha Valley, from the ruins of an Inca fortress. A 6.3 m organic core was obtained from the centre of the « lake » which has provided a detailed record of environmental changes over the last 4000 years…
- A lot of what I say below is give you a bigger picture of what is happening. But you may just want to cut it down in speaking to the last 1000 years in relation in the run-up to the Inca Empire. This is a simplified pollen diagram from Marcacocha, where just a few of the pollen types are shown-more like a cartoon. It shows the number of pollen grains for a centimeter cubed of sediment (i.e. pollen grains/cm3). As I said the 4200 year record represents 6.3 m of lake sediment. The Inca Period (ie the expansion of the Empire between AD 1400-1533) is a very short period, indicated by both the red astrerisk and the red line. To the right is the archaeological chronology for the Cuzco area, devised by Brian Bauer, a renown archaeologist, who has worked in the Cuzco area for many years, with whom this work was published. Essentially, the cultural changes, defined by pottery or archaeological remains, can be dated, with which we make our environmental comparison. The yellow bands mark drier intervals, when the lake level goes down (and often corresponding with cultural changes) as indicated by the sedges (Cyperaceae) colonizing those newly exposed wet areas. As we have discussed, a big change occurs about 2700 years ago, when maize pollen appears for the first time (and an important demographic expansion occurs-called the Late Formative, which corresponds in the north with the rise of the Chavin). Simultaneously, there is also a subsequent decline in Chenopodiaceae pollen, which includes crops such as quinoa and their wild relatives.-Similarly Ambrosia pollen ( which comes from a single species, a large shrub, A. arborescens) indicating soil erosion, but also used to stabilize the soil really shows a major decline at the same time. Farming practices may have changed at this time, including increased weeding and from archaeobotanical evidence elsewhere, a shift to using mostly cultivated quinoa and relatives, and less of the wild Chenopods, i.e. less emphasis on hunter-gathering. Subsequently, maize pollen (which is particularly large and poorly dispersed for pollen, being often larger than 75 microns) makes its appearance during brief arid (and presumably warmer intervals) when people could move up opportunistically to the altitude of Marcacocha at 3350 m and cultivate it. Maize is grown on the drained slopes just up from the lake today, but not that much good quality maize at higher altitudes (though that may change in the future). Unfortunately, we cannot say much about potatoes (or the other tubers), being insect pollinated (and hence occurring in low abundances), and there are numerous other Solanums in the Andes to confuse matters. We are still waiting for a good technique to indicate potatos,(maybe some biomarker?) but they are certainly very important at the altitude of the lake and above. The lake is at the boundary in this area for maize/potato cultivation. But for the purposes of the audience, is to note the abundance of Alnus pollen from about 1100 AD. This is the only alder (aliso) in South America, and its altitudinal migration reflects the increasing temperatures of the Medieval Warm Period. Being wind pollinated it is very abundant and easy to see in the pollen record, unlike many other plants which are insect pollinated-including other trees which would have moved up unnoticed in the pollen record. Before 1100 AD, Aliso is hardly visible in the record, and pollen beforehand probably is only from long distance wind transportation, not the tree itself growing near the the lake. The first appearance of aliso occurs after the « collapse » of the Wari and at the same time as the cultural group, the Killke appear (the proto-Inca), recognised by their pottery. This tree is of significance as it was the only fast and straight growing tree in the Andes, necessary in roof and lintel construction, for example, as well as being nitrogen fixing-hence improving soils. No doubt soon after its migration to higher altitudes, people followed to exploit the new agricultural areas available, as shown by the maize cultivation. The potato zone would also have been pushed up to much higher altitudes (ie here in the Patacancha it is between 3400 m up to 4100 m). No doubt aliso, was an easy tree to have in agro-forestry systems, but although it required wetter areas, the climate although warmer here, was not necessarily wetter, and its needs were supplemented by meltwater available due to the increase in warming. Not shown here is the record of aquatic and semi-aquatic plants that show the lake became much shallower about the same time as aliso moved up the valley from AD 1100, and subsequent to the arid interval (as indicated by the sedges), which assisted in the « collapse » of the Wari. The inorganics can be considered as a measure of erosion (by water or even bringing dust) into the lake, but we shall talk about this later. I don’t want to overload you with too much information, so the next diagram you can ignore-but it is just to show you the mechanism of how the lake responded during arid intervals, and was colonized at the edges by sedges, and later totally filled in about AD 1840, and was covered with further sedges. Aliso is still an important tree in the Andes today, but it has been somewhat usurped by eucalyptus, which can be very detrimental to local water needs (and ecologically). A local tree planting NGO, ECOAN is planting more aliso in the Patacancha Valley, but this we will also talk about later.
- This is a clear diagram just to show the increase of Alder pollen in relation to the Medieval Warm Period, and even increasing dryness as recorded in the Quelccaya ice core-ie when layers are thinner, less precipitation has fallen to form the ice layers and vice versa (but remember the ice core was taken at over 5600 m asl and is over 100 km southeast of Marcacocha, whereas Marcacocha is recording what is happening on the ground where the people are living. And as I said this was one of the most important trees to the Inca as it grew straight. Most of the diagrams I have given you, the labels can be changed to Spanish. This one was generated some time ago, and I do not have the original diagram for switching labels, as it was created with Blue Peter technology, with curves being lined up on a piece of paper and using cellotape, if not sticky black plastic! So you would have to stick with it, or put labels over the top in power point. The Tiwanaku and Wari are grouped together as the Middle Horizon in some chronologies, and likewise the Late Intermediate Period, includes many groups in Peru, one of whom were the Killke. Bloody archaeologists. All the same it is a diagram that makes it easy to explain the warming that allowed the alder, aliso, to move up the mountains-and the people too. So the pollen tells us something about the rise of the Medieval Warm Period, and how trees moved up the mountains, followed by the people, as supported by the archaeological record-showing after AD 1100 that occupation of sites occurred higher up which had never been on this scale before. There is also another newly developed technique, which tells us about the history of pastoralism and trade, and fertilizers available, by using…
- A lot of what I say below is give you a bigger picture of what is happening. But you may just want to cut it down in speaking to the last 1000 years in relation in the run-up to the Inca Empire. This is a simplified pollen diagram from Marcacocha, where just a few of the pollen types are shown-more like a cartoon. It shows the number of pollen grains for a centimeter cubed of sediment (i.e. pollen grains/cm3). As I said the 4200 year record represents 6.3 m of lake sediment. The Inca Period (ie the expansion of the Empire between AD 1400-1533) is a very short period, indicated by both the red astrerisk and the red line. To the right is the archaeological chronology for the Cuzco area, devised by Brian Bauer, a renown archaeologist, who has worked in the Cuzco area for many years, with whom this work was published. Essentially, the cultural changes, defined by pottery or archaeological remains, can be dated, with which we make our environmental comparison. The yellow bands mark drier intervals, when the lake level goes down (and often corresponding with cultural changes) as indicated by the sedges (Cyperaceae) colonizing those newly exposed wet areas. As we have discussed, a big change occurs about 2700 years ago, when maize pollen appears for the first time (and an important demographic expansion occurs-called the Late Formative, which corresponds in the north with the rise of the Chavin). Simultaneously, there is also a subsequent decline in Chenopodiaceae pollen, which includes crops such as quinoa and their wild relatives.-Similarly Ambrosia pollen ( which comes from a single species, a large shrub, A. arborescens) indicating soil erosion, but also used to stabilize the soil really shows a major decline at the same time. Farming practices may have changed at this time, including increased weeding and from archaeobotanical evidence elsewhere, a shift to using mostly cultivated quinoa and relatives, and less of the wild Chenopods, i.e. less emphasis on hunter-gathering. Subsequently, maize pollen (which is particularly large and poorly dispersed for pollen, being often larger than 75 microns) makes its appearance during brief arid (and presumably warmer intervals) when people could move up opportunistically to the altitude of Marcacocha at 3350 m and cultivate it. Maize is grown on the drained slopes just up from the lake today, but not that much good quality maize at higher altitudes (though that may change in the future). Unfortunately, we cannot say much about potatoes (or the other tubers), being insect pollinated (and hence occurring in low abundances), and there are numerous other Solanums in the Andes to confuse matters. We are still waiting for a good technique to indicate potatos,(maybe some biomarker?) but they are certainly very important at the altitude of the lake and above. The lake is at the boundary in this area for maize/potato cultivation. But for the purposes of the audience, is to note the abundance of Alnus pollen from about 1100 AD. This is the only alder (aliso) in South America, and its altitudinal migration reflects the increasing temperatures of the Medieval Warm Period. Being wind pollinated it is very abundant and easy to see in the pollen record, unlike many other plants which are insect pollinated-including other trees which would have moved up unnoticed in the pollen record. Before 1100 AD, Aliso is hardly visible in the record, and pollen beforehand probably is only from long distance wind transportation, not the tree itself growing near the the lake. The first appearance of aliso occurs after the « collapse » of the Wari and at the same time as the cultural group, the Killke appear (the proto-Inca), recognised by their pottery. This tree is of significance as it was the only fast and straight growing tree in the Andes, necessary in roof and lintel construction, for example, as well as being nitrogen fixing-hence improving soils. No doubt soon after its migration to higher altitudes, people followed to exploit the new agricultural areas available, as shown by the maize cultivation. The potato zone would also have been pushed up to much higher altitudes (ie here in the Patacancha it is between 3400 m up to 4100 m). No doubt aliso, was an easy tree to have in agro-forestry systems, but although it required wetter areas, the climate although warmer here, was not necessarily wetter, and its needs were supplemented by meltwater available due to the increase in warming. Not shown here is the record of aquatic and semi-aquatic plants that show the lake became much shallower about the same time as aliso moved up the valley from AD 1100, and subsequent to the arid interval (as indicated by the sedges), which assisted in the « collapse » of the Wari. The inorganics can be considered as a measure of erosion (by water or even bringing dust) into the lake, but we shall talk about this later. I don’t want to overload you with too much information, so the next diagram you can ignore-but it is just to show you the mechanism of how the lake responded during arid intervals, and was colonized at the edges by sedges, and later totally filled in about AD 1840, and was covered with further sedges. Aliso is still an important tree in the Andes today, but it has been somewhat usurped by eucalyptus, which can be very detrimental to local water needs (and ecologically). A local tree planting NGO, ECOAN is planting more aliso in the Patacancha Valley, but this we will also talk about later.
- The purpose of this diagram is to show the history of oribatid mites over the 4200 year record at Marcacocha, and therefore the history of camelid excrement (pastoralism, trade), at least until the Spanish arrive. It is the same as the original pollen diagram, but now with the oribatid mite record added. I would use it mostly for pointing out that the first appearance of maize corresponds with a major peak of oribatid mites about 2700 years ago. We know from the archaeoogical record that society became more complex and sedentary at this time, with a major demographic increase. So it is by no coincidence that there were more camelids around using the pasture, perhaps even using the trading route this far back-and the availability of camelid excrement probably helped boost maize (and potato) production. The diagram also clearly identifies a peak of oribatid mites during the Inca interval (red asterisk) but we can look at this in more detail in the next diagram. It is just intereresting to place the Inca in a longer perspective at the top of all the societies that have gone before them.
- This diagram shows the oribatid mite history (= large herbivore excrement, pastoralism, trade) in more detail over the last 1200 years, with a very distinctive peak during the Inca Empire. (the dots on the topright are the dates provided by Pb210 dates and the black asterisks below are radio-carbon dates-this is just so you know, you don’t have to talk about these). What is important is to spell out is that the peaks of oribatid mites (=large herbivores in the pasture) can be corroborated by historical events after the arrival of the Spanish. Numbered 1-5 With the large peak during the Inca Empire (1) there would have been lots of caravans of llamas travelling to and fro from the mountains to the selva bringing products in both directions, for example salt from the Cuzco area, and coca leaves back from the jungle. They would be using the excellent pasture around Marcacocha. (2) Sees the collapse of the Inca Empire. Indigenous populations collapsed through diseases, or were moved from the countryside into settlements (which made them even more vulnerable to diseases!), or even moved down to places such as Potosi to work in the silver mines. The trading systems using llamas as pack animals would have broken down, or the llamas were pushed up to graze at higher altitudes, or trading directions re-orientated in terms of supplying other areas with food such as Potosi (llamas later replaced by mules, etc). It was also not just the humans who died of diseases, but two-thirds of the llamas in the Cuzco area are reported by the Spanish chroniclers soon after they arrived to have caught a skin mange, most of whom were killed and buried. (3) Sees somewhat of a recovery of rural populations and probably the replacement of camelids at this altitude by herbivores from the Old World, using the pasture around Marcacocha:horses, cattle, sheep, goats, etc. (4) Suddenly a major collapse of human and livestock populations in the late 1600s-early 1700s. This was not only the coldest conditions of the Little Ice Age, as well as 4 major El Nino events during this period (bringing droughts), but a smallpox epidemic in 1719 nearly killed all the native people in the Patacancha Valley, and was known to have killed in a single day in Cuzco, over 600 people in 1720 (as recorded in historical documents). (5) Sees the recovery of rural populations and livestock. The decline in oribatid mites that occurs above this you don’t necessarily need to mention, but it is when the lake is infilling, and finally peats are deposited on top and it is no longer a lake, but a wetland. The numbers of oribatid mites are greatly diluted in the peats, so that the numbers are not comparable with the lake sediments below. Two other points of interest from this diagram. First is that the N% often increases when there are the oribatid mite peaks, in part reflecting the addition of more nitrogenous matter derived from excrement and urine entering the lake. The second is the C% record, which is an indicator of how C rich the sediments are, and this decreases when inorganic material is brought by erosion into the lake. What is particularly noticeable is as people move up the valley after AD 1100. There is a striking peak between AD 1100-1200, unique to the complete core (shown by a ?), of a layer of large shaley clasts often larger than 2 cm (much smaller in the rest of the record when there is inorganic material), which have not travelled far-i.e. very local. It was a difficult barrier to core through. We think this represents the period when major re-landscaping was going on, i.e. the terraces and irrigation canals were being constructed. And until that stability was created, it meant there was a brief window when the landscape was vulnerable to erosion. Subsequently, one sees very little erosion (ie inorganic material) enter the lake, except when it finally infills at c. AD 1850, and animals may have been trampling on the surface. One last thing to consider in relation to Inca land management, is fire, as this is a recurring problem today, especially when fires get out of control (even around Machu Picchu)….
- Oribatid mites. The message is the more the oribatid mites (found in the lake sediments), the more the excrement that was deposited, the more camelids (and later other large herbivores after the Spanish conquest) visiting the pasture around the lake. The oribatid mites lived in the lake of Marcacocha and on the wet surface of the wetland today. They are not eating directly the large herbivore excrement, but when it starts to break down as they are detritivores. Initial studies seems to show they are dominated by one species, or at least one genus called Hydrozetes, being investigated by Anne Baker at the Natural History Museum in London. Not much taxonomy of oribatid mites has been carried out in recent years in Peru. Our assumption is that populations of this mite respond rapidly to extra food available, i.e. the broken down remains of excrement. What does not enter the lake or get broken down in pools of water in the wetland, in the past, would have been gathered for fertilizer, fuel, etc. by the local people. By the way, the oribatid mites when alive look more like spiders, but when they die the first thing to drop off are their limbs. This one may appear to be waving, but it may just be drowning… in broken down excrement. In Inca times, it would have been camelids using the pasture. With the arrival of the Spaniards, camelids were pushed up to higher altitudes, and cows, horses, etc. used the pasture (as today as shown in the top right photo). So now to look at the record of oribatid mites=excrement=large herbivores within a longer time perspective….
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …..How much of the Andean landscape was re-landscaped to maximize food production, as shown here in the Patacancha Valley around Marcacocha. Although most of the irrigation canals fell into disuse with the arrival of the Spanish, water was available all the year to be chanelled by canal systems to terraced fields, as the Patacancha River flows throughout the year, even during the dry season (May-October) due to the additional supply of meltwater. Terracing was vital for reducing soil erosion and conserving the moisture and nutrients in the soils. And although the Spanish noted « bare hillsides with patches of trees », they recorded the importance that was placed by the Inca on tree conservation, and the harsh laws if trees were illegally felled. And as we shall show certain tree species were invaluable to the Inca, as recorded both in historical documents by the Spanish (the Inca had no written system as such-just the quipu). In fact, important planted trees were revered with the same word for a dead ancestor « mallki », whereas « sacha » was used for a wild tree. Now is the time to look at the Inca time interval more clearly, but within a longer perspective from the lake sediment record obtained from the infilled lake of Marcacocha (X) to assess some of the lines of evidence about which we have speculated…
- The last 1000 years+, including the Inca Period (signalled by the red asterisk) is distinguished by some burning, but no massive events compared to many significant events in the previous 3000 years (especially in the early part of the record). Is this a management issue or climate change? Or both. We are not sure. (The topmost peats at 50 cm depth since AD 1840 are not part of the comparison as charcoal is probably very diluted in the peats). One might expect more macrocharcoal/potential for burning with more human activity/larger populations at higher altitudes, with more agriculture and pastoralism, and even more biomass, with for example, trees such as alder (and others) moving up the mountains, compared to earlier in the record,. But this is clearly not the case and this is also recorded in many other records in the Andes. Did earlier people really make such a big impact on the landscape by burning? It has been assumed that trees were not common earlier in the record, for example, from 4000 years ago, but it might be possible that the pollen record is not seeing them as they are insect pollinated, including trees, for example, in the genera Escallonia and Myrcianthes (which exist still in the Patacancha Valley today). Just for your interest, but you don’t have to say anything about it, but the C/N ratio gives a measure of how much terrestrial matter is entering the lake. When it is close to 20 or over (for which it is much of the time), it is dominated by organic terrestrial input. For example, when the lake completely infills before peat deposition takes over, there is a big peak of C/N. The shallowing of Marcacocha, as shown by the macro-remains/cm3, i.e. of plants colonizing the margins (Juncaceae=rushes) or aquatics favouring shallow water (Charophytes=stoneworts) have always suggested that it was largely a dry interval, but this may have to be re-evaluated, if it can be argued that this is just the natural process of the lake getting shallower. One thing is for sure and that is from 4000 years ago, the lake was en route to dying as a lake, and from 1000 years ago, this process of shallowing indicated by the above plants (as shown iin the diagram), especially the charophytes, was accelerated. There is no way of reversing the process, short of digging the sediment out of the lake. Once again this diagram shows the erosional layer (indicated by the blue arrow) when we consider major re-landscaping took place (terracing, irrigation canal construction), after which little erosion is noticeable and the landscape is stabilized. The previous diagram used a more refined technique to measure C%, whereas this one has inorganics%, measured by heating off the organic component at 550°C, and recording the difference in weight, and calculating that difference in relative terms (%). It also shows a little erosion after the collapse of the Inca Empire, when people were not there to maintain terraces, etc. And now it might be worth quickly showing the effects of recent climate change since Marcacocha was cored in 1993, and also some of the strategies to alleviate some of the negative effects of climate change that may be employed by working together with the local populations for ensuring water supply and reducing the damage caused by major erosional events, as the climate becomes less predictable and erratic. This is not quite my field, but I will supply a few suggestions and observations-which probably apply during the Inca Period. It is hard to believe that they were not also faced by major climate challenges and uncertainties. There are probably lots of places where you want to add something, or make it relevant to crop and other tuber production. You can decide if you want to trim out some of the overheads, in case I am giving you too much information.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- This is the place of the Qoyllur Riti festival, which attracts annually more than 10,000 indigenous people, that takes place in late May or early June, east of Cuzco, near Ocongate. The photo shows a comparsion between the renown indigenous Cuzco photographer, Martin Chambi and a more recent photo taken by the explorer, Paolo Greer (well known also for his archival discoveries in showing that there were maps and a lot of activity by Westerners in the Machu Picchu area before Hiram Bingham). The comparison clearly shows a major reduction in glaciers today. The situation is so marked that at one time pilgrims used to return with glacial ice with its holy properties to their communities (to heal the sick, water the fields and give to the livestock), but this is today forbidden-as it is realized how quickly it is disappearing. So returning now back to Marcacocha-and the Patacancha Valley, as an example of one valley, what can be done to help reduce the impact of climate change, and possibly most importantly to conserve the water, when the glacial source supplementing the Patacancha River completely disappears, as well as how to reduce major soil erosion during extreme events?…
- There needs to be protection of the river banks, as when vegetation is removed- as in this case a large specimen of aliso along the Patacancha River-it increases the risk of eroding away river banks-and potentially fields. This photo was taken in 1996.
- Now to look briefly at some of the problems and solutions that might reduce the impacts that climate change may pose-and regardless of climate change, pragmatic ways of managing the landscape, both for sustaining rural populations and biodiversity. The photo above compared with the Guaman Poma drawing shows the continuity of collecting firewood through time, but we know the Inca very carefully managed their woodland resources. Curiously a few large trees, such as this relict Chachacoma (Escallonia resinosa) at 3700 m asl show just how large some of the trees can grow at high altitude. This one would predate the Inca Period, and may reflect the initial migration of trees up the mountains a 1000 years ago or been planted very early. Its protection may be due to Inca laws originally, but it might also classify as a « mallki »=dead ancestor, and would certainly be revered still today. If examples like this did not exist, one would not believe trees could get so large at these altitudes-and for doubters of the Medieval Warm Period in the Andes, here is another line of evidence. Sadly, Escallonias are insect pollinated and it is virtually invisible in the pollen record, and only future macro-charcoal work (or other evidence) will help elucidate its history. Mick Frogley took this photo on a trip to a lake called Yanacocha surrounded by Polylepis forest at 4000 m asl above Yucay in the Sacred Valley in 2003. In the photo is the renown botanist, Alfredo Tupayachi Herrera and the president of the NGO, ECOAN, Constantino Aucca Chutas, with whom we have had a very fruitful collaboration all these years.
- Most of the landscape is without trees in the upper part of the Patacancha Valley, where a few native trees survive within walled small farmsteads. This is a very typical one in Huilloc (c. 3600 m asl), next to a tributary on the right side of the Patacancha River when following the river upstream. You can also see the freeze dried potatoes lying out in different piles. So as I said one soon moves into the potato and tuber zone above Marcacocha, which is at 3350 m asl.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.
- This is where I diverge a little in my comments from the slide, and what the reality is. But this is not necessarily what you are meant to talk about. I came to work in the Patacancha Valley in 1993 because an english lady called Ann Kendall (=Cusichaca Trust) had rightfully noticed the importance of the little infilled lake of Marcacocha. She had a team of voluntary archaeologists working for three seasons between 1993 and 1996 on an archaeological site less than 100 m away from it (a great site, but out of which very little published work has ever emerged). All this has relevance as you shall see. Ann Kendall was an ex-archaeologist who considered that Inca terraces and canals could be restored with local people and traditional technology, to boost agricultural productivity and arrest the migration of local people to the cities. Her rural development project in the Patacancha Valley lasted between 1987-1997, including the amazing restoration of the 6 km Pumamarca canal to irrigate the Choquebamba terraces in the picture above (supposedly 160 hectares). She also had projects to improve the diets of local people. I thought the project had all been a great success, and she moved on to another long-term rural development project in the Pampachiri area, lasting even longer than ten years. Anyway, when I returned in 2005 having never seen the completed project to do with the restored canal, I was taken by the engineer, who had been involved with it for 5 years. A year after the canal was finished in 1998, it was largely abandoned, except for a small bit at the end fed by a waterfall (which had breached the canal bringing the water from more than 5 km away). The engineer was in tears as he showed me. In later years, I walked the canal more than ten times between the end of 2007-end of 2009. Some of it further up had been destroyed by damage caused by extracting logs from a eucalyptus plantation above it and dragging them down the hillside. Nevertheless, much of the canal is a marvel of construction, but apparently it was one of those projects driven more by the ideas of a gringo than by the local people, who were happy to find any employment at the time. Afterwards, instead of local people staying to work the land (a road was built to these terraces for transporting crops but most of the time subsequently was blocked by landslides), it was more lucrative to find work linked with the Inca Trail. Many of the terraces in the view above were certainly not under maize or any other cultivation. Perhaps, the Patacancha Valley was just too to close to the tourist magnet to carry out these kind of projects, but I like to think her projects in Pampachiri worked out better. This is not a judgement on the work. It is just what happened. Sadly, with all these projects, there are no reports to show what occurs afterwards (for the outside world and the donors)-and even on the website for the Cusichaca Trust, you would think it was all a great success. Meanwhile, other NGOs arrive (as Cuzco is a nice place to have an NGO and bring donors to) and think they are inventing the wheel, without knowing the failures of those who have gone before. Ann Kendall also set up a museum in Ollantaytambo, which was opened by Princess Anne-and seems to have disappeared since-although it was a great little museum, covering all aspects of the Patacancha Valley. Anyway, a little history for you. I’ll take you on the canal walk if we can ever get to Cuzco at the same time.
- Similar to the last image, cattle are allowed to graze at some of the highest altitudes. This photo is above 4000 m asl. This can cause major damage to the Polylepis forests, as well as preventing regeneration. This is less of a problem now that the NGO, ECOAN works very closely with the local communities. These Polylepis forests are also important for the local people as they contain medicinal plants and dyes for textiles. Besides their importance for controlling the water being released, they also have a number of endemic birds and other fauna, which are limited to these patches of forest-which makes them of global significance.
- In the Patacancha Valley, the high altitude forests of Polylepis need to be protected (and expanded). There is a Cuzco based NGO (ECOAN) which is doing this, as well as planting other native trees in the lower valley, such as Aliso. There is a small fragment of Polylepis forest above Huilloc around a small lake called Queuñacocha (=Polylepis Lake, 4200 m asl). In contrast, there is a completely different kind of forest, up the tributary of the Patacancha river (at c. 3400 m asl), northwest from Pallata, dominated by Myrcianthes oreophylla (Unka), endemic to Peru. Both provide examples of very likely much larger forested landscapes in the past.
- I am sure you will have your own ideas in relation to what approaches may be potentially most beneficial, including conserving crop varieties, etc. and promoting the role of CIP.
- You may not need to even use this diagram at all, but it is just for your understanding to show that Cyperaceae pollen gets deposited during low lake levels and when the lake gets infilled. Since this diagram was made, we now know that the sedges are dominated by the species Scirpus californicus subsp. tatora , also called totora. So in fact, it would be the same species at the edge as covering it. Although there are several species of rushes (Juncaceae) in the wetland, which in the northern Hemisphere look like totora, it is in fact all totora as shown in the photo with the dark circle. Really all you need to say is that sedges covered the lake or appear when the lake-levels are low. Honestly, I am trying to simplify the story without giving you too much detail-and this is a good exercise for me as well.
- Although we are considering the Medieval Warm Period (MWP; sometimes known as the Medieval Climatic Anomaly), which has slightly variable time boundaries depending where in the world it is examined, Lonnie Thompson who is renown for his investigations of tropical ice cores in the Andes and elsewhere, considered it between AD 1000-1520. Nevertheless, the subsequent Little Ice Age (which may have continued until as late as AD 1880, does not have a major impact until the late 17th and early 18th centuries-so it did not impact on the Inca Empire. For the moment, though the MWP is an important part of our story, let’s think about the Cuzco area (and the Central Andes) in terms of a longer perspective, and what could make the area special. It is probably no coincidence that major cultural centres in the Andes arose in areas of high biodiversity. There is a positive relationship between the conditions which are important in processes of biological diversification and those which appear to contribute to the establishment of human population centres (Fjeldsa and Rahbek). In this area, this « ecological stability » as quoting Fjeldsa and Rahbek is due amongst other requirements to predictable water supplies (in the long term), and these authors highlight the presence of cultural centres in warm montane basins immediately adjacent to mountain ridges and sustained cloudiness. Also, an important feature is that the rivers in valleys north of the Sacred Valley are fed often not just by rainfall, but glacial water and with an increase in warming (but not excessive) there is more water available throughout the year. Certainly in this area there are endless niches for crop relatives to evolve at the different altitudes and in the valleys separated from each other, as shown in this photo above Marcacocha, taken about 8.30 am in August 1996. The glacier of Nevado Halancoma is visible behind. For many crops, including the potato, the process of domestication has probably been going on for at least the last 5000 years in the Central Andes, especially after the end of the mid-Holocene aridity event (c. 8000-5000 years ago). It has been estimated that at the time of the Spanish conquest, the Inca were cultivating at least 70 crop species, but….
- But first now a little background to the Inca and their immediate predecessors. As many of us already know, at it’s height, the Inca Empire (AD 1400-1533) stretched from its centre at Cuzco to the modern Colombian border and down to central Chile, from the highlands down to the coast, and although expansion was restricted into the selva, much trading still took place. This is a very short period of time for what was achieved, but with the capture of the Inca leader, Atahualpa, by the Spanish in 1532 in Cajamarca, the Empire rapidly collapsed, followed by a massive reduction of the indigenous population by introduced diseases. However, its origins are much earlier, as a group of people in the upper Cuzco Valley (see previous map) from possibly as early as AD 1000, identified by a distinctive pottery type known as Killke, and bit by bit, this group was to expand locally geographically by various means, ranging from outright conquest to alliances based on strategic marriages, to occupy for example the very fertile Sacred Valley. However, we must not forget their predecessors.
- Before the Inca, there were two major empires, the Wari and the Tiwanaku. They both « collapsed » about AD 1000/AD 1100 in what has been considered protracted droughts, leaving behind many smaller groups, including the Killke (proto-Inca) in the upper part of the Cuzco Valley. Many technologies, such as irrigation, terracing, crop knowledge (and organizational systems, such as quipu-the counting system using knots) would have been passed on, but as we shall see climate change played a major role in allowing larger areas at higher altitude to be exploited later on. A factor in the collapse of the Tiwanaku, largely based around Lake Titicaca, was the vulnerability of their raised field systems (camellones) which required water fed by precipitation supplying springs. Similarly vulnerable was the site of Pikillacta in the photo above, a huge Wari administrative site, down the Cuzco Valley, above the Lucre Basin (in the direction of Lake Titicaca-shown on map already)-built on a grid system, without taking the landscape into account (and in an arid area by contrast to the Sacred Valley). It was constructed well above the level of Lake Huacarpay below. Water could be channeled to it by vulnerable viaducts and canals, but not from the lake. Evidence suggests major burning of the site by the subjugated population at the end. It was only following the protracted drought that populations could begin to slowly move up the mountains to exploit new agricultural areas to which I shall return, but this was not possible during the Wari Period as too cool for most of the time, and hence crops such as maize could largely be grown only below 3000 m. However, with increased warming post AD 1100 in the Cuzco area, there was also meltwater available from the glaciers-which I probably shall keep repeating.
- …was this demographic expansion possible with the absence of maize, originally from Central America, and not common as a major crop in the high Andes, probably until about 3000-2700 years ago. The Medieval Warm Period meant that with increased warming, the agricultural zones could be moved up, with good quality maize being grown up to 3400 m, and potatoes and other tubers reaching over 4000 m in the Cuzco area. However, neither should we under-estimate the importance of the native crops. Probably an opportunity for you to say something or even add a slide if you want. But let’s consider a few other factors.