Plants with male and bisexual flowers on the same plant are better mothers

Apr 30, 2007
Male and Bisexual Flowers in Horsenettle
Male (left) and bisexual (right) flowers in horsenettle (Solanum carolinense). Credit: Mario Vallejo-Marin

What would be the opening chapter of the Kamasutra of plant sex? A good pick would be a description of the numerous ways in which plants arrange their sexual organs: from both sexes in the same flower to sexes separated in different flowers or individuals. One widespread sexual strategy that remains an evolutionary enigma is the production of both male and bisexual flowers in the same plant, which occurs in approximately 4000 species.

What is the advantage of producing these redundant male flowers? Mario Vallejo-Marin and Mark Rausher, evolutionary biologists from Duke University, report that producing male flowers can make a plant a better mother, in the May issue of the American Naturalist.

The authors showed this counter-intuitive benefit of a "male" strategy through a series of field experiments with horsenettle, a common weed in North Carolina. The experimental demonstration that male flowers can sometimes increase seed number supports a new interpretation that male flowers increase not only male but also female reproductive success.

So what is the mechanism through which male flowers increase female reproductive success? Such a benefit may arise if resources saved by producing smaller male flowers are reallocated to increased seed production, if male flowers are more attractive to pollinators, or if male flowers remove less pollen from pollinators than bisexual flowers, thus increasing the amount of non-self pollen available for fruit-producing flowers. Which one of these mechanisms is responsible for the "good mothers" in Vallejo-Marin and Rausher's study?

"We don't know yet," says Mario, "but these alternatives could easily be tested through more experiments." Data from an unrelated study indicate that the female advantage of producing male flowers is not unique to horsenettle. To what extent strategies traditionally interpreted as "male" also benefit female fitness in other species remains an open and interesting question.

Source: University of Chicago

Explore further: Adventurous bacteria

add to favorites email to friend print save as pdf

Related Stories

A roly-poly pika gathers much moss

Dec 17, 2013

In some mountain ranges, Earth's warming climate is driving rabbit relatives known as pikas to higher elevations or wiping them out. But University of Utah biologists discovered that roly-poly pikas living ...

Chanel, UCSB's corpse flower, blooms and causes a big stink

Jul 31, 2013

Chanel, UC Santa Barbara's corpse flower, has finally spread her odiferous wings, broadcasting a stench that smells like a cross between rotting flesh and Limburger cheese. "It's disgusting," said UCSB junior Connor Way, ...

Recommended for you

Adventurous bacteria

33 minutes ago

To reproduce or to conquer the world? Surprisingly, bacteria also face this problem. Theoretical biophysicists at Ludwig-Maximilians-Universitaet (LMU) in Munich have now shown how these organisms should ...

Japan lawmakers demand continued whaling

1 hour ago

Japanese lawmakers on Wednesday demanded the government redesign its "research" whaling programme to circumvent an international court ruling that described the programme as a commercial hunt dressed up as ...

Revealing camouflaged bacteria

2 hours ago

A research team at the Biozentrum of the University of Basel has discovered an protein family that plays a central role in the fight against the bacterial pathogen Salmonella within the cells. The so cal ...

User comments : 0

More news stories

Adventurous bacteria

To reproduce or to conquer the world? Surprisingly, bacteria also face this problem. Theoretical biophysicists at Ludwig-Maximilians-Universitaet (LMU) in Munich have now shown how these organisms should ...

Revealing camouflaged bacteria

A research team at the Biozentrum of the University of Basel has discovered an protein family that plays a central role in the fight against the bacterial pathogen Salmonella within the cells. The so cal ...

How kids' brain structures grow as memory develops

Our ability to store memories improves during childhood, associated with structural changes in the hippocampus and its connections with prefrontal and parietal cortices. New research from UC Davis is exploring ...

Gate for bacterial toxins found

Prof. Dr. Dr. Klaus Aktories and Dr. Panagiotis Papatheodorou from the Institute of Experimental and Clinical Pharmacology and Toxicology of the University of Freiburg have discovered the receptor responsible ...