Navigation Links
High-speed video and artificial flowers shed light on mysteries of hummingbird-pollinated flowers
Date:11/20/2012

How flowers have evolved particular colours, shapes and scents to attract pollinators has long fascinated ecologists. Now, using artificial flowers and high-speed video, researchers have gained intriguing insights into the intimate relationship between hummingbirds and the flowers they pollinate. The study, published in the British Ecological Society's journal Functional Ecology, is the first to measure how much energy hummingbirds use while hovering to feed from flowers of different orientation.

Hummingbirds are among the smallest and most brightly-coloured birds on Earth, and one of the only types of bird capable of hovering for long periods. They are also crucial pollinators of flowering plants across the Americas. Hummingbird-pollinated flowers are usually red, tubular-shaped and have no smell, characteristics that have been well-studied by ecologists. Why most hummingbird-pollinated flowers hang down vertically, however, has remained a mystery.

Working with Anna's hummingbirds (Calypte anna) the most common hummingbird species on their university campus Dr Nir Sapir and Dr Robert Dudley of the University of California, Berkeley built a series of artificial "flowers". The artificial flowers, which pointed horizontally, vertically-downwards or were tilted 45 degrees downward, supplied nectar to the birds.

After training the hummingbirds to feed from the artificial flowers, the researchers used high-speed video to record how flower orientation affected the birds' body position and hovering style while feeding. They then fitted the artificial flowers with a mask to measure the amount of oxygen and hence how much energy the birds used to hover while feeding.

The results revealed that to feed from flowers hanging down vertically, the hummingbirds had to adopt a "bizarre" body position, with their bodies upright and heads bent back, and that doing so required 10% more energy than feeding from horizontal flowers.

The results are intriguing, says Dr Sapir: "Because flowers need pollinators to reproduce, flowers have evolved to attract pollinators. Almost all hummingbird-pollinated flowers hang down vertically, so our hypothesis was that they evolved this way because hummingbirds would have to use less energy to feed from them. We found the opposite that it's more costly in energy terms for hummingbirds to feed from these flowers."

In evolutionary terms, this means other factors must be at play. "Our findings suggest other factors may be dictating flower orientation. Flowers may need to exclude less efficient pollinators, such as insects, and so flowers that hang down vertically may be selected during evolution to increase pollination efficiency. And horizontal flowers are more exposed to rain, which can dilute the amount of nectar in a flower, and we know that hummingbirds can tell how sweet nectar is, so they may select downward-facing flowers because their nectar is less diluted by rain and thus contains the most sugar."


'/>"/>

Contact: Becky Allen
beckyallen@ntlworld.com
44-012-235-70016
Wiley
Source:Eurekalert

Related biology news :

1. BGI and Aspera collaborate on high-speed data exchange to advance genome research
2. Video-article shows how to purify magnetic bacteria
3. Can videogaming benefit young people with autism spectrum disorder?
4. Video-gaming fish play out the advantages of groups
5. Chemistry on Mars video with Curiosity Rover from the American Chemical Society
6. New video series highlights the people who fuel Americas innovation pipeline
7. First ever videos of snow leopard mother and cubs in dens recorded in Mongolia
8. Pre-surgical steps for eye surgery are standardized through JoVEs video publication
9. Camera trap video offers rare glimpse of worlds rarest gorilla
10. Spanish researcher releases a video showing a beetle from the inside
11. Nature: Video reveals wave character of particles
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/18/2016)... 2016  Extenua Inc., a pioneering developer of ... and access of ubiquitous on-premise and cloud storage, today ... Cyber.  ... C4ISR and Cyber initiatives in support of National ... technology solutions," said Steve Visconti , Extenua ...
(Date:1/11/2016)...  higi, the leading retail and omni-channel community engagement ... and mobile, today announced it has closed funding ... --> --> ... higi,s health platform – its network of health ... expanding services and programs to retail partners and ...
(Date:1/7/2016)... , Jan. 7, 2016  A United States ... the first court in the country to interpret a ... lawsuit to go forward against the photo website Shutterfly ... BRIAN NORBERG vs. SHUTTERFLY, INC.; and ... plaintiff alleges that Shutterfly violates the Illinois Biometric Privacy ...
Breaking Biology News(10 mins):
(Date:2/4/2016)... -- ContraVir Pharmaceuticals, Inc. (NASDAQ: CTRV ), a ... targeted antiviral therapies, announced today that it will present ... held February 8-9, 2016, at the Waldorf Astoria New ... Healthcare Conference, taking place in New York ... Sapirstein , Chief Executive Officer of ContraVir, will provide ...
(Date:2/4/2016)... Brooklyn, NY (PRWEB) , ... February 04, 2016 , ... ... cuvettes for over 10 years. What sets them apart from other cuvette ... that is posted on their website. On top of this steady flow of ...
(Date:2/3/2016)... and HOLLISTON, Mass., Feb. 3, 2016 Harvard ... a biotechnology company developing bioengineered organ implants for ... today announced that CEO Jim McGorry , ... Investor Conference on Tuesday, February 9, 2016 ... York City . HART,s presentation will be ...
(Date:2/3/2016)... , ... February 03, 2016 , ... ... annual report which summarizes and analyzes nearly 750 unique supply chain ... alert, and analysis service. , Supply chain risk management practitioners subscribe to ...
Breaking Biology Technology: