The berries of the Pentadiplandra plant are sweet to humans and other primates, but not gorillas. Gorillas may have evolved to no longer desire to eat this berry, since it is low-calorie and hence, low-energy.

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The berries of the Pentadiplandra plant are sweet to humans and other primates, but not gorillas. Gorillas may have evolved to no longer desire to eat this berry, since it is low-calorie and hence, low-energy.