Sunbirds Use Unique Tongue Suction to Drink Nectar

Sunbirds drink nectar by generating suction with their tongues, making them the first known vertebrates to use this method ^[1].

This discovery challenges previous assumptions about how nectar-feeding birds operate and highlights a distinct evolutionary path. While sunbirds and hummingbirds both feed on nectar, their biological mechanisms for doing so are entirely different.

Researchers at the University of California, Berkeley said the findings were reported in April 2026 ^[2]. The study observed sunbirds in their natural habitats across Africa and Asia to determine how they extract liquid from flowers ^[4]. The team said these small nectar-feeding passerine birds use a tongue-generated suction mechanism to pull nectar into their mouths ^[1].

This mechanism stands in direct contrast to the method used by hummingbirds ^[1]. According to the research, hummingbirds do not use suction but instead employ a sponging action to collect nectar [1, 3]. The distinction suggests that these two groups of birds evolved similar dietary habits through different biological adaptations.

The ability to create suction is an evolutionary adaptation that allows sunbirds to extract nectar efficiently [1, 2]. By utilizing their tongues to create a vacuum, they can draw liquid upward more effectively than through simple capillary action, or sponging.

Scientists used video analysis to confirm the movement of the tongues during the feeding process ^[2]. The observations confirm that the suction is generated specifically by the tongue's movement rather than by the bird's throat or cheeks ^[1].