印加文明是在南美洲西部、中安第斯山区发展起来的又一著名的印第安古代文明。它的影响范围大体说来包括了现今厄瓜多尔山区部分、秘鲁山区部分、玻利维亚高原地区、半个智利和阿根廷西北部。据考古学家的研究，上述这一广大地区是美洲最早出现农业的地区，时间大约在公元前8000年。到公元前3000年，沿海地区的居民已定居下来。到公元前2000年末，中安第斯山区已出现一系列古代文化中心。在公元前1000年中下期，发达的农业文化已经形成，这奠定了印加文明的基础，并出现了阶级和国家的最早形式。这标志文明开始形成。公元10世纪后半叶以后，中安第斯山区出现了各种文化相互渗透和兼并的局面。导致了一些原有文化的衰落和消失，并在此基础上形成了印加入统一中安第斯山区前的各种文化基础。

印加国是一个奴隶制国家，奴隶主阶级包括印加王、王室贵族、高级官吏和祭司。他们不从事生产劳动，过着奢侈的生活。印加王被称为太阳之子，神的化身，拥有至高无上的权力，独揽国家一切政治、军事和宗教大权。为了维护自己的统治，印加王建立了以中央集权为中心的政治制度，他通过各级官吏，牢牢地控制着全国。除了政权机构外，印加奴隶主还拥有一支20万人的训练有素的常备军队，用其对外扩张，对内镇压反叛力量。印加帝国还建立了严厉的司法制度，用来维护奴隶主阶级的利益。为了巩固自己的统治，印加王还采取了一些文化和经济措施。例如，对于那些刚被征服的地区，强行推广克丘亚语。再者，在全国大兴道路和释站，修建了条条道路通京城的交通网，以利于对边远地区的控制。

印加人能在中安第斯山区建立这样一个幅员辽阔的国家，与当地的发达的经济文化是分不开的。 在农业方面，印加人继承前人的成就，在干旱缺水的山区修建了水渠和梯田，使粮食生产得到稳定发展，保证了非农业人口的需要。印加人的水渠和梯田修筑得非常坚固，有些水渠至今还在使用。印加人培育了大约40多种作物。他们还饲养骆马和羊驼，成为美洲印第安人中唯一饲养大牲畜的人民。这些动物的饲养不仅为人民提供了肉食和毛皮，而且还为农业生产提供了优质肥料，这反过来又促进了粮食产量的提高。

印加人的金属加工业比较发达，他们不但懂得金、银、铜、铅、锡、汞的冶炼，还会冶炼各种合金，并知道利用汞来提纯黄金。有研究认为，印加人的金银装饰品，其技巧可与欧洲文艺复兴时相比。印加入的纺织技术也达到了较高的水平。远在公元前2000年，他们就会纺纱织布了。他们的毛织品和棉织品花色多样，色彩调和，制作精细。如lO00年前留下来的一幅地毯，每英寸含绒纱500根，而欧洲中世纪同类织物却只有100根。在南部沿海皮斯科附近出土的木乃伊套服，被称作是“世界纺织品的奇迹之一”。在医药学方面，印加人的成就也令人惊叹。他们的外科手术特别是穿颅术在当时居于世界先进行列。手术刀主要是一种“T”形铜刀，非常锋利。与外科手术相伴而生的麻醉术，印加人也是内行。印加人知道多种草药，如奎宁、可可等。

但是，英国泰晤士报于2009年7月27日7:55以另外一个全新的观点刊登了一篇关于印加文明的文章。

Climate change helped the Incas build civilization

Their warfare, building and agricultural skills may have been impressive but, according to scientists in Peru, the Incas would have been nothing without good weather induced by climate change.

New research has revealed that a prolonged period of warm weather between AD1100 and 1533 cleared large areas of mountain land to be used for farming, helping the Incas to spread their influence from Colombia to the central plains of Chile.

With the tree line moving steadily higher up the mountains, the Incas carved terraces into the mountainside to grow potatoes and maize, and developed a system of canals to irrigate the land.

The climate remained dry but melting glacial ice provided a constant supply of water, resulting in a surplus of crops to feed the population.

The men freed up from agricultural duties were then able to focus on other activities, among them constructing roads and buildings such as the Incas' 3,250-mile Royal Road through the highlands, the 2,520-mile Coastal Road and Machu Picchu, the Lost City of the Incas.

Dr Alex Chepstow Lusty, a British people working for the French Institute for Andean Studies in Lima, Peru, said the clement（mild）weather also freed up men to fight in the Inca's ambition and expansionist Army.

"Yes, they were highly organised, and they had a sophisticated hierarchical system, but it wouldn't have counted a jot without being underpinned by the warming of the climate," he told The Times. "It was the perfect incubator for the expansion of a civilisation."

Dr Chepstow Lusty and his team made their discovery by analysing sediment on the floor of a small lake called Marcacocha, 11,000 feet above sea level in the Peruvian Andes near Cuzco, the cradle of the Incan civilisation.

The layers of sediment at different heights represent different periods of time, like rings in the trunk of a tree. The scientists found suggestions of trees and crops at the critical time, suggesting the tree cover had moved upwards.

Dr Chepstow Lusty believes modern civilizations have much to learn from the pre-Columbians when it comes to the environment. He wants to see controlled deforestation and the increased growing of crops on terraces using glacier melt as irrigation.

"Such methods increase crop yields. In fact, they are beginning to be reintroduced by the local populations,” he told the French scientific publication CNRS.

reveal [ri‵vi:l] vt.显示; 露出

Her laugh revealed her even teeth.

她一笑就露出了她那整齐的牙齿。

泄露; 透露

He never revealed his identity.

他从未暴露过自己的身份。

terrace [‵terəs] n. 梯田

The people here grow rice on terraces.

此地的人们在梯田里种植水稻。

maize [meiz] n.玉米

There's a field planted with maize behind the house.

房子后面有一块玉米地。

irrigate [‵iriɡeit] vt.灌溉

They have built canals to irrigate the desert.

他们建造成水渠以灌溉沙漠。

冲洗(伤口)

Irrigate his nose and throat with hot water

用热水冲洗他的鼻喉

surplus [‵sə:pləs] adj.过剩的, 多余的

The manufacturers in some countries dumped their surplus commodities abroad.

一些国家的制造商向国外倾销过剩产品。

n.过剩

The United States tried to dispose of its grain surpluses. 美国努力把过剩粮食处理掉。

sophisticate [sə‵fistikeit] adj.老练的

hierarchical [‵haiə‵rɑ:kikəl] adj.分等级的

underpin [‵ʌndə‵pin] vt.加强; 巩固

incubator [‵iŋkjəbeitə]

n.孵化器、(用于放置早产婴儿的)恒温箱

sediment [‵sedimənt]

n.沉淀物

The sediment settled and the water was clear.

杂质沉淀后, 水变清了。

cradle [‵kreidl]

n.摇篮

The child slept soundly in her cradle.

那孩子在摇篮里睡得很熟。

发源地, 发祥地

Tokyo was the cradle of Japanese culture.

东京是日本文化的发源地。

婴儿时期

They knew each other from the cradle.他们自幼相识。

suggestion [sə‵dʒestʃən]

n. 细微的迹象

I detected a suggestion of malice in his remarks.

我觉察出他说的话略带恶意。

deforestation [di‵fɔris‵teiʃən]

n.采伐森林