Skip to Main Content
Insect outbreak shifts the direction of selection from fast to slow growth rates in the long-lived conifer Pinus ponderosaAuthor(s): Raul de la Mata; Sharon Hood; Anna Sala
Source: PNAS. 114(28): 7391-7396.
Publication Series: Scientific Journal (JRNL)
Station: Rocky Mountain Research Station
Download Publication (1.0 MB)
DescriptionLong generation times limit species' rapid evolution to changing environments. Trees provide critical global ecosystem services, but are under increasing risk of mortality because of climate change-mediated disturbances, such as insect outbreaks. The extent to which disturbance changes the dynamics and strength of selection is unknown, but has important implications on the evolutionary potential of tree populations. Using a 40-y-old Pinus ponderosa genetic experiment,we provide rare evidence of context-dependent fluctuating selection on growth rates over time in a long-lived species. Fast growth was selected at juvenile stages, whereas slow growth was selected at mature stages under strong herbivory caused by a mountain pine beetle (Dendroctonus ponderosae) outbreak. Such opposing forces led to no net evolutionary response over time, thus providing a mechanism for the maintenance of genetic diversity on growth rates. Greater survival to mountain pine beetle attack in slow-growing families reflected, in part, a host-based life-history trade-off. Contrary to expectations, genetic effects on tree survival were greatest at the peak of the outbreak and pointed to complex defense responses. Our results suggest that selection forces in tree populations may be more relevant than previously thought, and have implications for tree population responses to future environments and for tree breeding programs.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
Citationde la Mata, Raul; Hood, Sharon; Sala, Anna. 2017. Insect outbreak shifts the direction of selection from fast to slow growth rates in the long-lived conifer Pinus ponderosa. PNAS. 114(28): 7391-7396.
Keywordsfluctuating selection, growth-survival trade-offs, selection response, Pinus ponderosa, Dendroctonus ponderosae
- Mountain pine beetle dynamics and reproductive success in post-fire lodgepole and ponderosa pine forests in northeastern Utah
- Water potential in ponderosa pine stands of different growing-stock levels
- Susceptibility of ponderosa pine, Pinus ponderosa (Dougl. Ex Laws.), to mountain pine beetle, Dendroctonus ponderosae Hopkins, attack in uneven-aged stands in the Black Hills of South Dakota and Wyoming USA
XML: View XML