Hummingbirds and Indian sunbirds

Source: The post is based on the article “Aztec hummingbirds and Indian sunbirds” published in The Hindu on 25th February 2023

What is the News?

A study found that the loss of a key gene, FBP2 makes Hummingbirds more efficient at breaking down sugar to use it for energy.

What are Hummingbirds?

Hummingbirds are small, colourful birds found throughout the Americas. There are over 300 species of hummingbirds.

They are known for their unique ability to hover in mid-air by rapidly flapping their wings, which can beat up to 50 times per second.

Hummingbirds feed on nectar from flowers and are important pollinators for many plant species. Tubular flowers that are bright red or orange (such as lantana and rhododendron) are preferred.

The energy demands of hovering are very high. Relative to their body mass, hummingbirds have the highest metabolic rate (calories burnt per minute) among vertebrates. 

– Most of this energy comes from nectar. Rapid sugar uptake by their digestive system ensures that they utilize energy from nectar ingested just a few minutes ago.

Their lungs are 10 times better at absorbing oxygen from the air than mammals of similar size.

Hummingbirds are capable of vocal mimicries like parrots and some songbirds. They are also able to align their muscular movements with auditory sensations that come to their ears, creating a dance.

What are the similarities between Hummingbirds and Indian Sunbirds?

Indian Sunbirds, though unrelated to Hummingbirds, share many common features through convergent evolution. They are part of the same Nectariniidae family.

Though slightly larger, the sunbirds can hover briefly, and go for bright, tubular flowers. They are critical pollinators of the ‘Flame of the Forest’.

As the energy demands of hovering are very high, sunbirds need to ‘perch’ while feeding, unlike Hummingbirds. Like hummingbirds, they may catch insects, especially to feed their young.