Abstract Detail



Ecophysiology

Avila-Lovera, Eleinis [1], Ashlock, Sarah [2], Vargas, Oscar M [3], Funk, Jennifer [4], Kay, Kathleen M [3], Goldsmith, Gregory R [5].

Plasticity, not genetic differentiation, drives trait-environment relationships in Neotropical understory herbs.

Environmental variation can lead to selection on plant functional traits that confer a fitness advantage and ultimately promote speciation. Alternatively, those traits may simply vary with environment through phenotypic plasticity, even in the absence of selection. Can we provide insights into what extent environment might promote the differentiation of species through plant functional traits? We studied how plant functional traits vary among species across environmental gradients, the extent to which that variation may be ascribed to environmentally-driven genetic differentiation, and to what extent trait values are influenced by shared evolutionary history. By combining field and common garden observations of >35 species of understory herbs (genus Costus), we addressed the following questions: 1) What is the nature of trait-environment relationships across temperature and precipitation gradients? 2) Do trait-environment relationships reflect underlying genetic differentiation or phenotypic plasticity? 3) How is phylogenetic signal differentially expressed in the field and common garden? We observed significant relationships between functional traits and environment in the field, which mostly disappeared when species were observed in a common garden environment. For example, stomatal conductance decreased, whereas stem density and rhizome dry matter content increased, as mean annual temperature and seasonality decreased. Species resembled each other more than expected by chance in both field and common garden experiment, but phylogenetic signal was higher in the latter. We concluded that trait values in the field are strongly related to key climate conditions, particularly with respect to variation in mean temperature and the seasonality of precipitation. Trait values are not fixed and can change plastically, as demonstrated by observing the same species at two or more sites and through observations in the common garden.


1 - Chapman University, Schmid College Of Science And Technology, 450 N Center St., Orange, CA, 92866, United States
2 - University of California, Santa Cruz, Ecology and Evolutionary Biology, 156 High St, Santa Cruz, CA, 95064, US
3 - University of California, Santa Cruz
4 - Schmid College Of Science And Technology, One University Drive, Orange, CA, 92866, United States
5 - Chapman University, One University Drive, Orange, CA, 92866, United States

Keywords:
Ecophysiology
Costus
climate
functional traits
phylogenetic signal.

Presentation Type: Oral Paper
Session: ECOPH3, Ecophysiology III
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 3:30 PM
Number: ECOPH3003
Abstract ID:595
Candidate for Awards:None


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