What was the ancient bowstring made of?

The most primitive is javelin, and later people made bows and arrows in order to save physical strength and increase the range. The original bows and arrows were made of bamboo. Later, it was gradually improved and replaced by solid materials such as animal horns and animal tendons. Later, a bow made of copper appeared, which was more durable. Ancient bowstrings were generally made of animal tendons, and now there are many better materials to choose from.

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