A HERB from South America can manipulate the sex ratio of its offspring, and is the first plant found to have this ability.
Many animals manipulate the sex ratio of their progeny, although often it is unclear how. But the evolutionary logic is simple: offspring of the rarer sex have a greater chance of finding a mate and siring grandchildren.
Now C茅sar Dom铆nguez and Sergio L贸pez at the Independent National University of Mexico in Mexico City have discovered that the herb Begonia gracilis gauges the number of nearby males by the amount of pollen it receives. When the researchers added extra pollen to plants, they found those that received the most pollen produced around 20 per cent more female flowers than those receiving low or medium pollen levels (Journal of Evolutionary Biology, vol 16, p 1177).
Advertisement