Abstract Detail

Recent Topics Posters

Park, Daniel [1], Potter, Daniel [2].

Why Close Relatives Make Bad Neighbors in the Thistle Tribe.

The number of exotic plant species that have been introduced into the United States far exceeds that of any other group of organisms, and many have become highly invasive. In the California Floristic Province (CAFP), a biodiversity hotspot, members of the Asteraceae, especially the thistle tribe, Cardueae, are highly problematic. While Darwin hypothesized that plant invaders closely related to native species would be at a disadvantage compared to more distantly related invaders, we found evidence that introduced thistles more closely related to native ones are more likely to become invasive. In order to elucidate the mechanisms behind this pattern, we modeled the ecological niches of thistle species present in the CAFP and calculated and compared the niche distances between taxa. Invasive species were found to have larger predicted niches than non-invasive introduced species, and pairwise niche distance was significantly correlated with phylogenetic distance, suggesting phylogenetic niche conservatism. We also found that invasive thistles have superior dispersal capabilities compared to non-invasive introduced species, and that these capabilities exhibit a phylogenetic signal. By analyzing the modeled ecological niches and dispersal capabilities of over a hundred species, we found that these traits are phylogenetically conserved to varying but significant degrees, offering insight into why close exotic relatives may make bad neighbors in the thistle tribe. We suggest that the both habitat filtering and dispersal ability are important in determining the invasion success of Cardueae species in the CAFP.

1 - Unversity of California, Davis, Plant Sciences, 3800 Solano Park Cir, #3923, Davis, CA, 95616, USA
2 - University Of California Davis, DEPARTMENT OF PLANT SCIENCES MAIL STOP 2, One Shields Avenue, Davis, CA, 95616-8780, USA

Keywords:
Asteraceae
Cardueae
invasive plants
niche modeling
dispersal
Thistle.

Presentation Type: Recent Topics Poster
Session: P
Location: /
Date: Monday, July 28th, 2014
Time: 5:30 PM
Number: PRT012
Abstract ID:1249
Candidate for Awards:None