Pollination by Flotation (IMAGE) Brown University Caption Some conifers still have buoyant pollen that, upon contact with an emitted droplet, float up into a downward facing ovule. The mechanism has been evolving out of existence. Credit Patrick Knopf Usage Restrictions with credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.