A species of primitive cycad plant from Australia relies on a surprisingly sophisticated system of meting out food to ensure successful pollination.
These plants take an active role in their reproduction by selectively attracting and repelling small insects known as thrips, a new study shows.
Scientists had long thought that cycads were passively wind-pollinated.
But in a push-pull system, male cones of this "living fossil" species heat up and emit strong odors to send pollen-bearing insects fleeing.
Female cones then emit a more attractive perfume to lure the bugs back in.
Pollination accomplished.
"I think the work demonstrates that plants aren't just sitting there looking pretty or just smelling good to attract their pollinators and that there's a lot more dynamics involved," said study co-author Irene Terry, a biologist at the University of Utah.
(Related: "Orchid Has 'Active' Sex With Itself—A Flower First?" [June 21, 2006].)
The mechanics of such primeval systems could provide insight into how pollination occurs in natural environments such as forests, something that Terry says there is still much to learn about.
The study appears this week in the journal Science and was funded in part by the National Geographic Society, which owns National Geographic News.
Nagging Mystery
Cycads are one ancient lineage of seed-producing plants called gymnosperms, which also include firs, spruce, pines, sequoias, and redwoods.
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