Hummingbirds are attracted to tubular shaped flowers for several key reasons. The tube shape of the flower correlates directly with the hummingbird’s long, slender beak and tongue which allows them to access the nectar at the base of the flower. Additionally, the red pigments found in many tubular flowers attract hummingbirds visually. Understanding why hummingbirds are drawn to these unique flowers helps us appreciate the specialized relationship between hummingbirds and their flower counterparts.
The Match Between Beaks and Flower Shape
Flowers pollinated by hummingbirds frequently have tube shaped blossoms which match the long, slender beaks of hummingbirds. Tubular flowers provide a perfect fit for the hummingbird’s beak and tongue which allows them to delve deep into the back of the flower to sip the nourishing nectar inside. The shape correlation between beak and flower tube means that the hummingbird can efficiently extract the maximum amount of sweet nectar.
In contrast, the beaks of other types of birds would not align properly with tubular shaped flowers. For example, sparrows have short sturdy beaks adept at cracking seeds but not well-suited to probe into narrow tubes. The slender bill of the hummingbird acts as an ideal “key” to unlock the nectar treasure hidden within the tube shaped flower.
Additionally, hummingbirds have bifurcated tongues which are essentially split down the middle. This forked tongue has tube-like channels along the edge which allow nectar to travel up the grooves in the tongue. When the hummingbird’s beak is inserted into a flower tube, the tongue neatly folds around the interior. Capillary action then draws the nectar up the channels in the tongue so the liquid can be swallowed. The tube shape of the tongue paired with tubular flowers allows hummingbirds to efficiently consume the maximum amount of sweet nectar fuel.
Red Flower Pigments Attract Hummingbirds
In addition to the mechanical fit between beak and flower, hummingbirds are also visually attracted to the color red. Many tubular shaped hummingbird flowers have brilliant red or orange hues which attract the hummingbird’s eye. Hummingbirds can see the color red exceptionally well which leads them to prefer and frequent red tubular flowers.
Hummingbirds have evolved with an excellent color sense to spot red flowers which are rich in nectar. Their visual acuity and color sensitivity is unmatched in the bird kingdom. Hummingbirds have four types of cones in their retinas which allow them to perceive red wavelengths particularly well. Since red flower tubes visually pop against green foliage, this color preference helps guide hummingbirds to plentiful nectar sources.
Interestingly, bees do not see the color red as vividly meaning red flowers specifically attract pollination by hummingbirds rather than bees. The red color essentially acts as an advertising signal guiding the hummingbird to its ideal energy source. This mutually beneficial relationship helps the hummingbird acquire food and helps the flower achieve pollination.
Specialized Adaptations Lead to Specialized Relationships
The precisely co-evolved match between tube shaped flowers and the anatomy of hummingbirds reveals an intriguing specialized relationship in nature. Plants which rely on hummingbirds for pollination have adapted tube shaped flowers which perfectly align to the beak and tongue of their pollinator. This shows an interdependent association between two organisms.
Over time, tubular flowers accessed by hummingbirds have evolved to attract these ideal pollinators. Bright red pigments grab the visual attention of hummingbirds leading them to land on the flower and probe inside with their slender beak. The inner tube shape ensures contact with the hummingbird’s head and body, allowing pollen to be transferred as the bird feeds on nectar.
Likewise, hummingbirds have adapted specialized anatomical traits to take advantage of tubular flowers as an energy source. This includes morphological adaptations like long slender beaks and bifurcated tongues. It also includes sensory adaptations like excellent vision attuned to the color red. Hummingbird and flower have evolved closely linked adaptations facilitating their mutualistic relationship.
Common Tubular Flowers Pollinated by Hummingbirds
Many types of tubular flowers depend specifically on hummingbirds for pollination and have evolved traits to attract these unique birds. Here are some of the most common tubular flowers pollinated by hummingbirds:
- Fuchsia
- Columbine
- Trumpet vine
- Penstemon
- Coral bells
- Cardinal flower
- Indian paintbrush
- Salvia
- Firecracker plant
- Marigold
These flowers share the tubular shape that provides an ideal access point for the slender beak and tongue of hummingbirds. Many also have the red or orange coloring that attracts hummingbirds by sight. By evolving to match hummingbird anatomy and vision, these flowers have established a specialized pollination relationship with hummingbirds.
Fuchsia
Fuchsia flowers have long tubular shaped blossoms which provide easy access to nectar for hummingbirds. Hanging vertically, the bright reddish-purple flowers are easily visible to hummingbirds searching for nectar. As hummingbirds insert their beaks and tongues into the flowers, pollen is transferred onto their heads. The co-evolved match between fuchsia tubes and hummingbird beaks makes them frequent partners.
Columbine
Columbine flowers feature elegant tubular nectaries containing sweet nectar perfectly matched to the long tongue of hummingbirds. Their distinctive shape has evolved to aid hummingbird pollination by limiting access to other pollinators. The downward hanging orientation of the columbine flower also allows hummingbirds to easily perch while drinking nectar.
Trumpet Vine
With long, flared tubular flowers in fiery shades of orange and red, trumpet vines are a magnet for hummingbird pollinators. The nectar is dispensed deep within the flower only accessible by the specialized beak and tongue of hummingbirds. As they drink from the trumpet-shaped blossoms, pollen is transferred on the bird’s head from flower to flower facilitating pollination.
Advantages of the Tube Flower Shape for Hummingbirds
The tubular flower shape provides several key advantages which make them attractive to hummingbirds:
- Nectar protection – The tube shape protects the inner nectar from rain and limits access to other insects and animals who cannot reach the nectar source.
- Specialized access – The narrow tube opening limits nectar extraction to hummingbirds with their specialized beak, tongue and head shape.
- Abundant nectar – Many tubular flowers produce generous amounts of sugary nectar to fuel the high metabolism of hummingbirds.
- Ideal pollination – As hummingbirds probe the tube opening, their head makes contact with pollen-coated anthers depositing pollen for cross-pollination.
- Color contrast – Many tubular flowers utilize bright red pigments which contrast sharply with green foliage attracting hummingbird vision.
Together these advantages make tubular flowers an ideal match for the physical design, sensory capabilities and nutritional needs of hummingbirds.
Conclusion
The unique characteristics of tubular flowers correlate directly with hummingbird anatomy and vision to create a highly specialized pollination relationship. Narrow tubes protect nectar while providing ideal access for hummingbird beaks and tongues. Bright red coloration attracts hummingbird vision leading them to abundant, pure energy. Hummingbirds in turn provide pollination services by transferring pollen between flowers as they feed. The co-evolution of these traits reveals the intricate interdependent relationships in nature and helps explain why hummingbirds favor tubular shaped flowers.
