Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sundews just want to be loved

18.08.2010
Why do some insect-eating plants like sundews keep their flowers so far away from their traps? New research suggests that it isn't a clever trick to keep pollinators safe, it's about getting pollinated

Sex can be complicated at the best of times, but plants have an extra difficulty. If you're a plant who relies on insects to pollinate your flowers and reproduce, you will want your flowerstalks to be long. That way your flowers are on display to insects above the crowd. But if your stalk is too long, you'll stand out to herbivores, and you flower will end up as someone's lunch.

It used to be thought that carnivorous plants like Sundews had the opposite problem. They reproduce better if they avoid eating insects that pollinate them, so a long stalk prevents an unfortunate meal. Simply looking at a plant, it's impossible to tell if the stalks evolved for sex or safety, but Bruce Anderson at the University of Stellenbosch has now found an answer to be published in the October issue of the Annals of Botany.

He examined two Sundews, Drosera cistiflora, which has a long stalk above its rosette of traps and Drosera pauciflora, which is more upright and has a shorter flower stalk. Both plants attract the same pollinators, so Anderson reasoned if a longer stalk is safer, D. pauciflora should accidentally catch more pollinators in its traps. To test his idea he observed the pollination of 500 plants of each species. Then he examined a sample of the traps to see what they had caught. Anderson said: "The pollinators all tended to be quite large, over 5mm. Most of them were monkey beetles. But the traps had a different catch. It's harder to say what many of them were exactly, because the Sundews left their bodies in poor condition, but they were small. Most were less than 2mm long. Only one plant had caught a pollinator. Statistically the length of the flower stems made no difference to the safety of the pollinators."

"But just because the stems didn't affect safety, it doesn't automatically follow that the other explanation, attracting pollinators, must be right by default. So I tested that too."

Flowers were cut from D. pauciflora and placed in test tubes. Some were set so the flowers were at normal height, while the other test tubes were buried so that the flower was barely above ground level. Anserson said: "Doing this meant there were few variables in the experiment. The flowers were identical. The only difference was their height. This way it's possible to simulate how well a Sundew that hadn't evolved a long stem could attract insects."

The results were emphatic. The taller flowers had ten times the number of visitors than the short flowers.

Anderson said: "There have been a few people who've suggested that the flower stalks are for attracting pollinators. However, the standard explanation in most textbooks is that the stems are to protect pollinators. It's a good story. It sounds like the kind of elegant solution that evolution comes up with. Now we have the hard data from these experiments and it shows that explanation is wrong. It's not about food, it's about sex. Sundews want to improve their chances of pollination and maximise their reproductive success."

Dr. David Frost | EurekAlert!
Further information:
http://www.le.ac.uk

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Individualized fiber components for the world market

23.06.2017 | Physics and Astronomy

How brains surrender to sleep

23.06.2017 | Life Sciences

Can we see monkeys from space? Emerging technologies to map biodiversity

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>