Seasonal climatic instability in the western Chinese Loess Plateau during Marine Isotope Stages 12–10

Previous studies have shown abundant eggs in the surface soils of China and in the upper part of the Huining section^7,9. After breaking some of these eggs, we observed embryonic land-snail shells inside the eggs^7,9, which demonstrates undoubtedly that the eggs we observed are laid by land snails.

Egg cannibalism is unlikely in the Huining section. Egg cannibalism occurs when the eggs are laid as a clutch. Hatching asynchrony of the eggs in the clutch may cause the earliest hatchlings to eat the unhatched eggs within the same clutch¹². However, the eggs in the Huining section are mainly from…