Click on an oval to select your answer. To choose a different answer,
click one different oval.
我的笔记 编辑笔记
For most of human history, we have foraged (hunted, fished, and collected wild plants)for food. Small nomadic groups could easily supply the necessities for their families. No one needed more, and providing for more than one's needs made little sense. The organization of such societies could be rather simple, revolving around age and gender categories. Such societies likely were largely egalitarian; beyond distinctions based on age and gender, virtually all people had equivalent rights, status, and access to resources.
Archaeologist Donald Henry suggests that the combination of a rich habitat and sedentism (permanent, year-round settlement) led to a dramatic increase in human population. In his view, nomadic, simple foragers have relatively low levels of fertility. Their high-protein, low-carbohydrate diets result in low body-fat levels, which are commonly associated with low fertility in women. High levels of physical activity and long periods of nursing, which are common among modern simple foragers, probably also contributed to low levels of female fertility if they were likewise common among ancient foragers.
In Henry's view, the adoption of a more settled existence in areas with abundant food resources would have contributed to higher fertility levels among the sedentary foragers. A diet higher in wild cereals produces proportionally more body fat, leading to higher fertility among women. Cereals, which are easy to digest, would have supplemented and then replaced mother's milk as the primary food for older infants. Since women are less fertile when they are breast-feeding, substituting cereals for mother's milk would have resulted in closer spacing of births and the potential for a greater number of live births for each woman. A more sedentary existence may also have lowered infant mortality and perhaps increased longevity among the aged. These more vulnerable members of society could safely stay in a fixed village rather than be forced regularly to move great distances as part of a nomadic existence, with its greater risk of accidents and trauma.
All of these factors may have resulted in a trend of increasing size among some local human populations in the Holocene (since 9600 B.C.E.). Given sufficient time, even in very rich habitats, human population size can reach carrying capacity, the maximum population an area can sustain within the context of a given subsistence system. And human population growth is like a runaway train: once it picks up speed, it is difficult to control. So even after reaching an area's carrying capacity, Holocene human populations probably continued to grow in food-rich regions, overshooting the ability of the territory to feed the population, again within the context of the same subsistence strategy. In some areas, small changes in climate or minor changes in plant characteristics may have further destabilized local economies.
One possible response to surpassing the carrying capacity of a region is for a group to exploit adjoining land. However, good land may itself be limited-for example, to within the confines of a river valley.Where neighbors are in the same position, having filled up the whole of the desirable habitat available in their home territories, expansion is also problematic. Impinging on the neighbors' territory can lead to conflict, especially when they too are up against the capacity of the land to provide enough food.
Another option is to stay in the same area but to shift and intensify the food quest there. The impulse to produce more food to feed a growing population was satisfied in some areas by the development of more-complex subsistence strategies involving intensive labor and requiring more cooperation and greater coordination among the increasing numbers of people. This development resulted in a change in the social and economic equations that defined those societies. Hierarchies that did not exist in earlier foraging groups but that were helpful in structuring cooperative labor and in organizing more-complex technologies probably became established, even before domestication and agriculture, as pre-Neolithic societies (before the tenth millennium B.C.E.) reacted to the population increase.
题型分类:推理题
题干分析:用题干问题发现整段都可能是定位范围。
选项分析:
选项A说他们更早地断掉了母乳喂养,来源于本段第四句“Since women are less fertile when they are breast-feeding, substituting cereals for mother s milk would have resulted in closer spacing of births and the potential for a greater number of live births for each woman”发现谷类可以代替母乳,正确;
选项B说他们体内脂肪含量更低,而第三段第二句说“produces proportionally more body fat”;与原文相悖;
选项C说他们吃的谷类种类更少了,而第三段第二句说“A diet higher in wild cereals”;与原文相悖;
选项D说他们更难得到容易消化的食物,而第三段第三句说“Cereals, which are easy to digest”,与原文相悖。
如果对题目有疑问,欢迎来提出你的问题,热心的小伙伴会帮你解答。