Identifying and comparing various organisms and animal bones, one must depend on the help of zoology. To analyze layers of rock, one must rely on geology. Soil testing must rely on the specialty of chemists.
年代的測定須藉助物理學上「碳十四」的測試；動物骨骼和植物花粉等的辨別、比較，靠動物及植物學者鼎力相助；地層分析仰賴地質學；土壤化驗則是化學家的專業… …。