Recombination and Speciation in the Annual Sunflowers

The greatest study ever done in my lab was conducted by Kate Ostevik, who completed a postdoc with Mark Braucher and is now an assistant professor at UC Riverside. Kate successfully carried out a reciprocal transplant on sand dunes, a challenging task due to the harsh conditions. Despite past difficulties faced by graduate students on the sand dunes, Kate was able to plant hybrids and parents in the area. These plants are often the only green vegetation on the sand dunes and are quickly consumed by animals. However, Kate was able to overcome these challenges and determine the strength of reproductive isolation between the dune and non-dune systems at different stages of the life cycle. Unsurprisingly, immigrant inability was identified as the strongest barrier due to the inability of small seeds from the non-dune ecotype to survive on the dunes.