Featured Research

from universities, journals, and other organizations

Study of flower petals shows evolution at the cellular level

Date:
November 17, 2011
Source:
University of California - Santa Barbara
Summary:
A new study of flower petals shows evolution in action, and contradicts more that 60 years of scientific thought. Columbine flowers, known as Aquilegia, evolved several lengths of petal spurs that match the tongue lengths of their pollinators, including bees, hummingbirds and hawkmoths.

Aquilegia longissima flower.
Credit: Scott A. Hodges

A new study of flower petals shows evolution in action, and contradicts more that 60 years of scientific thought.

The findings are reported by a scientist from UC Santa Barbara and a research team from Harvard University in the Proceedings of the Royal Society B this week.

Columbine flowers, known as Aquilegia, evolved several lengths of petal spurs that match the tongue lengths of their pollinators, including bees, hummingbirds, and hawkmoths. The petal spurs are shaped like a tubular pocket and contain nectar at the tip. The spurs grow from 1 to 16 centimeters in length, depending on the species.

The research team discovered that longer spurs result from the lengthening of cells in one direction, called anisotropy, and not from an increased number of cells. This finding contradicts decades of scientific thinking that assumed the elongated petals form via continued cell divisions.

"When we went in and looked at this in detail, we found that even the super-long-spurred flower doesn't differ much in cell number from the short-spurred one," said Scott A. Hodges, professor in the Department of Ecology, Evolution, and Marine Biology at UCSB.

He said that most studies of shape, particularly of leaves and of some flower parts, have focused their attention primarily on genes controlling cell division. "What this study is saying is that you don't want to just look at those kinds of characteristics; here's this whole other way to produce a tremendous amount of shape diversity without involving cell divisions," said Hodges.

In long-spurred plants, the spurs reach the same length at the same point in time as the short-spurred flowers, but they keep on growing, said Hodges. The rest of the flower has to wait for the spurs to lengthen. Until then, the pollen can't be released and the ovules are not ready to be fertilized. The flower has to stop that part of development while the spurs grow. Then, almost a week later, those flowers become reproductive, after the spurs have grown longer.

The evolution of petal spurs in columbines is considered a textbook example of adaptive radiation. Like Darwin's finches, over time, the columbines evolved a variety of species to exploit different ecological niches. The short-spurred columbines can be easily pollinated by bees. Hummingbirds have long beaks and tongues and can pollinate flowers with spurs of medium length. Hawkmoths have very long tongues and can pollinate columbines with the longest spurs, such as Aquilegia longissima.

In addition to Hodges, the co-authors are Joshua R. Puzey, Sharon J. Gerbode, Elena M. Kramer, and Lakshminarayanan Mahadevan, all from Harvard University.


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. R. Puzey, S. J. Gerbode, S. A. Hodges, E. M. Kramer, L. Mahadevan. Evolution of spur-length diversity in Aquilegia petals is achieved solely through cell-shape anisotropy. Proceedings of the Royal Society B: Biological Sciences, 2011; DOI: 10.1098/rspb.2011.1873

Cite This Page:

University of California - Santa Barbara. "Study of flower petals shows evolution at the cellular level." ScienceDaily. ScienceDaily, 17 November 2011. <www.sciencedaily.com/releases/2011/11/111117144041.htm>.
University of California - Santa Barbara. (2011, November 17). Study of flower petals shows evolution at the cellular level. ScienceDaily. Retrieved August 31, 2014 from www.sciencedaily.com/releases/2011/11/111117144041.htm
University of California - Santa Barbara. "Study of flower petals shows evolution at the cellular level." ScienceDaily. www.sciencedaily.com/releases/2011/11/111117144041.htm (accessed August 31, 2014).

Share This




More Plants & Animals News

Sunday, August 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Raw: Australian Sheep Gets Long Overdue Haircut

Raw: Australian Sheep Gets Long Overdue Haircut

AP (Aug. 28, 2014) Hoping to break the record for world's wooliest, Shaun the sheep came up 10 pounds shy with his fleece weighing over 50 pounds after being shorn for the first time in years. (Aug. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Dramatic Diversity of Columbine Flowers Explained by a Simple Change in Cell Shape

Nov. 15, 2011 Columbine flowers are recognizable by the long, trailing nectar spurs that extend from the bases of their petals, tempting the taste buds of their insect pollinators. New research helps to explain ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins