What symbiosis is a hummingbird?

Hummingbirds participate in a fascinating symbiotic relationship with certain flowering plants. Symbiosis refers to two or more organisms living in close association with each other, typically to the benefit of both. In the case of hummingbirds and plants, the hummingbird gets nectar as a food source from the flower, while the plant gets pollinated by the hummingbird. This relationship allows both species to thrive.

What is symbiosis?

Symbiosis refers to any type of long-term interaction between two different biological species. There are three basic types of symbiosis:

• Mutualism – a relationship where both species benefit
• Commensalism – a relationship where one species benefits and the other is unaffected
• Parasitism – a relationship where one species benefits at the expense of the other

The relationship between hummingbirds and flowering plants is an example of mutualism, where both species provide a benefit to the other. The hummingbird gets energy-rich nectar from the flower, while the plant gets pollinated by the hummingbird carrying pollen from flower to flower. This mutualistic symbiosis allows both species to obtain food and reproduce more effectively.

The coevolution of hummingbirds and flowering plants

Hummingbirds and many flowering plants have evolved together over time, adapting in ways that promote each other’s survival. This process is known as coevolution. Here is a brief overview of how this coevolution occurred:

• Flowering plants started developing nectar as a nutritional offering to attract pollinators.
• Hummingbirds evolved long beaks and tongues to reach nectar, gaining the ability to hover and fly backwards.
• Plants evolved trumpet-shaped flowers perfectly suited for hummingbird beaks and tongues.
• Hummingbirds became specialized nectar feeders, relying on the nectar for energy.
• Plants adapted flowering times and colors to match hummingbird migration and vision.

Through these coadaptive changes over thousands of years, the hummingbird-flower relationship became increasingly specialized and interdependent. The evolution of each species promoted the survival of the other.

Examples of hummingbird-pollinated flowers

Many flowering plants depend specifically on hummingbirds for pollination. Here are some common examples:

• Cardinal flower – Produces bright red tubular flowers loaded with nectar.
• Columbine – The nectar-rich flowers are red and trumpet-like.
• Fuchsia – Dangling red and purple flowers appeal to hummingbird tastes.
• Trumpet vine – Bright orange tubular flowers depend on hummingbirds.
• Salvia – Nearly 1,000 species of this nectar-filled plant genus are pollinated by hummingbirds.
• Coral bells – Numerous tubular flowers provide a constant nectar source.

These plants share certain adaptations that perfectly match the feeding abilities of hummingbirds:

• Bright, vibrant flower colors – Attracts hummingbirds
• Tubular flower shape – Perfectly fits hummingbird beaks and tongues
• Abundant nectar – Provides the energy hummingbirds need
• Little to no scent – Hummingbirds rely on vision, not smell

Without hummingbird pollination, many of these plants would struggle to reproduce and survive. This demonstrates the interdependent nature of the symbiotic relationship.

How hummingbirds and flowers interact

When a hummingbird feeds from a flower, an intricate process of interactions takes place:

1. The hummingbird spots a flower using keen color vision attuned to red and orange hues.
2. It rapidly beats its wings up to 70 times per second to fly in place while feeding.
3. The long, slender beak and tongue extend deep into the flower to lap up nectar.
4. As the bird feeds, its head picks up pollen from the flower’s anthers.
5. The pollen sticks to the hummingbird’s head and beak.
6. When it flies to the next flower, some of this pollen rubs off onto the stigma.
7. This pollinates the flower, allowing it to develop seeds and fruit.

This precisely choreographed system perfectly coordinates the needs of both species. The rapid wing beating while hovering is a unique adaptation that allows hummingbirds to exploit energy-rich nectar sources.

Why this relationship benefits both species

The symbiotic relationship between hummingbirds and flowering plants is mutually beneficial for several key reasons:

• Food source – The nectar provides hummingbirds with an abundant, high-energy food source.
• Energy needs – Hummingbirds have very high metabolisms and energy needs that nectar is perfectly adapted to meet.
• Pollination – The hummingbirds transfer pollen from flower to flower, enabling the plants to reproduce.
• Survival – Both species rely heavily on the other for nourishment and reproductive success.
• Distribution – Hummingbirds carry pollen far and wide, spreading the plant species.
• Evolution – The complementary adaptations show how the species evolved together.

Without this symbiosis, it is likely that both hummingbirds and many specialized flowering plants would be less abundant and more restricted in their ranges. The mutualistic benefits enhance survival for both groups of species.

Threats to this symbiotic relationship

Though hummingbird-flower interactions have persisted for millennia, some threats put this symbiosis at risk:

• Habitat loss from development, logging, and agriculture
• Pollution and pesticide use which reduce insect food sources
• Invasive plant species that crowd out native flower diversity
• Climate change affecting patterns of flowering and migration
• Disease, predators, and competition from other pollinators

Maintaining intact ecosystems and mitigating climate change are key to preserving this delicate symbiotic balance. Protecting areas of high hummingbird and flowering plant diversity is crucial.

Unique characteristics of hummingbirds

Hummingbirds have many unique evolutionary adaptations that enable their symbiotic relationship with flowers:

• Rapid wing beats – Up to 70 beats per second allows hovering in place
• Rotating wings – Allows flight in all directions necessary to feed while hovering
• Lightweight – Weighs 2-20 grams, the smallest birds
• Long beak and tongue – Adapted for drinking nectar from flowers
• High metabolism – Extremely rapid breathing, heart rate, and food intake
• Migratory ability – Some species migrate remarkably long distances
• Color vision – Excellent color sight tuned to the colors of nectar flowers
• Aggressive territoriality – Defends nectar-rich flower resources

These specialized traits equip hummingbirds to take advantage of energy-rich nectar and play their essential role as pollinators. Their unique lifestyle is exquisitely intertwined with the many flowers they feed from.

Keytakeaways

• Hummingbirds and specialized flowers evolved together in an ecologically interdependent manner.
• Access to nectar helps hummingbirds meet their high energy needs and fuels their rapid metabolisms.
• By transporting pollen, hummingbirds enable the plants to reproduce successfully.
• Their complementary traits and needs are evidence of how mutualistic symbiosis benefits both parties.
• This relationship is threatened by habitat loss, climate change, and other environmental disruptions.
• Preserving intact ecosystems can help maintain this 50+ million year old partnership.

Conclusion

The symbiosis between hummingbirds and flowering plants showcases how closely intertwined two species can become through evolutionary time. This relationship exemplifies mutualistic symbiosis, where both parties provide vital benefits to the other. Hummingbirds rely on nectar to fuel their metabolically demanding lifestyles, while plants depend on hummingbirds for pollination, reproduction, and genetic exchange. This delicate interaction has shaped the characteristics and natural histories of both groups of organisms. Ensuring the health of ecosystems where these interactions take place is key to preserving this beautiful natural wonder. Though facing some threats, the hummingbird-flower symbiosis persists as a stunning example of nature’s intricate coevolutionary handiwork.