What ability allows species like Cacajao to survive the non-fruiting periods in the Amazonian floodplains?

Answer

Switching reliance from high-sugar fruit to higher-fiber/protein diet

The ability to switch reliance from a high-sugar fruit diet to a higher-fiber/protein diet, relying on seeds and insects, allows them to survive non-fruiting periods.

What ability allows species like Cacajao to survive the non-fruiting periods in the Amazonian floodplains?
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