Hummingbirds, with their iridescent feathers and rapid wingbeats, are captivating creatures known for their specialized feeding habits. Their reliance on floral nectar fuels their active lifestyles, but the mechanism behind their efficient consumption of this sugary liquid is more complex than it appears. The hummingbird’s tongue, a unique and highly adapted organ, plays a central role in this process, allowing these tiny birds to thrive.
The Remarkable Length of a Hummingbird Tongue
A hummingbird’s tongue is notably long, often reaching a length comparable to or even exceeding its head or bill. For common species like the Ruby-throated or Anna’s Hummingbird, the tongue can extend around 1.5 inches, nearly one-third of their 3.75 to 4-inch body length. Some tropical species, particularly those with elongated beaks, possess even longer tongues, occasionally reaching 3 to 4 inches. The Sword-billed Hummingbird, for instance, has a tongue up to 4 inches long, nearly matching its body length. When not actively feeding, this long tongue retracts and coils around specialized structures within the bird’s skull, supported by the hyoid apparatus.
The Science Behind Nectar Collection
For many years, it was believed that hummingbirds collected nectar using capillary action, much like a straw. However, high-speed photography and recent research have revealed a more dynamic mechanism. The hummingbird’s tongue is not a simple tube but a sophisticated liquid-trapping device, functioning like a micropump. Its structure is key: the tongue is forked at the tip, splitting into two slender halves. These halves are lined with numerous tiny, hair-like structures called lamellae.
When a hummingbird extends its tongue into nectar, the forked halves spread, and the lamellae unfurl. As the tongue contacts the liquid, these lamellae efficiently soak up the nectar, similar to how a brush absorbs water. Upon retraction, the lamellae quickly fold inward, trapping the nectar between the two halves of the tongue. This action is fast, with hummingbirds flicking their tongues in and out 12 to 20 times per second. This rapid feeding method, relying on the tongue’s elastic properties rather than muscular effort, allows hummingbirds to consume large quantities of nectar to sustain their high metabolic rates.
Beyond Nectar: Other Uses of the Tongue
While primarily associated with nectar feeding, the hummingbird’s tongue also plays a role in its broader diet. Nectar provides energy from sugar, but hummingbirds also require protein, fats, and minerals for growth and health. These nutrients are obtained by consuming small insects and spiders.
Hummingbirds catch tiny prey items by snatching them in mid-air (“hawking”) or picking them from leaves and branches (“gleaning”). Their beaks are adapted to snap shut at high speeds to capture insects. Although their tongue is highly specialized for nectar, it does not function as a sticky trap or pincer for manipulating insects. Instead, hummingbirds typically swallow small insects whole. This protein-rich diet is important for growing nestlings and adult birds during energy-demanding periods like nesting and migration.