What is the importance of the dots, lines, and symbols engraved on stone, bones and ivory?刻在石头、骨头和象牙上的点、线以及符号究竟有什么重要性呢？
Future historians will be in a unique position when they come to record the history of our own times.未来的历史学家在记录我们这个时代的历史时，将会处于一个非常独特的地位。
They will hardly know which facts to select from the great mass of evidence that steadily accumulates.他们几乎无法从不断积累的大量证据中判断出应该选择哪些事实。
What is more, they will not have to rely solely on the written word.此外，他们将不必仅仅依赖书面文字。
Films, videos, CDs and CD-ROMs are just some of the bewildering amount of information they will have.电影、视频、CD以及CD-ROM只是他们所拥有的海量信息中的一部分而已。
They will be able, as it were, to see and hear us in action.他们将能够，可以说是，亲眼看到我们的活动，亲耳听到我们的声音。
But the historian attempting to reconstruct the distant past is always faced with a difficult task.但是，试图重建遥远过去的历史学家总是面临着一项艰巨的任务。
He has to deduce what he can from the few scanty clues available.他必须从现有的一些零星线索中尽可能地进行推断。
Even seemingly insignificant remains can shed interesting light on the history of early man.即使是一些看似微不足道的遗物，也能为了解早期人类的历史提供有趣的线索。
Up to now, historians have assumed that calendars came into being with the advent of agriculture, for then man was faced with a real need to understand something about the seasons.到目前为止，历史学家们一直认为日历的出现是与农业的诞生同时发生的。因为那时，人类确实迫切需要了解关于季节变化的规律。
Recent scientific evidence seems to indicate that this assumption is incorrect.最近的科学证据似乎表明，这一假设是不正确的。
Historians have long been puzzled by dots, lines and symbols which have been engraved on walls, bones, and the ivory tusks of mammoths.历史学家们长期以来一直对这些刻在墙壁上、骨头以及猛犸象象牙上的点、线条和符号感到困惑。
The nomads who made these markings lived by hunting and fishing during the last Ice Age which began about 35, 000 B.C. and ended about 10, 000 B.C.制造这些标记的游牧民族在最后一次冰河时代（大约始于公元前35000年，结束于公元前10000年）以狩猎和捕鱼为生。
By correlating markings made in various parts of the world, historians have been able to read this difficult code.通过将世界各地留下的标记进行关联分析，历史学家们已经成功解读了这段难以理解的代码。
They have found that it is connected with the passage of days and the phases of the moon.他们发现这与日期的流逝和月亮的相位有关。
It is, in fact, a primitive type of calendar.实际上，这是一种非常原始的日历形式。
It has long been known that the hunting scenes depicted on walls were not simply a form of artistic expression.人们早就知道，墙上描绘的狩猎场景并非仅仅是一种艺术表达形式。
They had a definite meaning, for they were as near as early man could get to writing.这些符号具有明确的含义，因为它们是早期人类所能达到的最接近文字的表达方式。
It is possible that there is a definite relation between these paintings and the markings that sometimes accompany them.这些壁画与有时伴随出现的标记之间可能存在某种明确的联系。
It seems that man was making a real effort to understand the seasons 20, 000 years earlier than has been supposed.看来，早在人们原先认为的时间之前2万年，人类就已经在努力理解四季的变化规律了。