Fujio explains that the regionality of the earthen figure use might be related to the difference in the main food supplies available in the regions, the difference between the regions where the main food supplies were the nuts, beech, oak, chestnut and buckeye etc., from the deciduous trees (that is, these regions covered with deciduous forests) and the regions covered with laurel forests in much of the western Japan.
こうした土偶の使用の地域性について藤尾は、ブナ、ナラ、クリ、トチノキなどの落葉性堅果類を主食とした地域（つまりこれら落葉樹林に覆われていた地域）と、西日本を中心とした照葉樹林帯との生業形態の差異と関連づけて説明している。