TY - JOUR
T1 - Why are evergreen leaves so contrary about shade?
AU - Lusk, Christopher H.
AU - Reich, Peter B.
AU - Montgomery, Rebecca A.
AU - Ackerly, David D.
AU - Cavender-Bares, Jeannine
PY - 2008
Y1 - 2008
N2 - Leaf mass per area (LMA) is one of the most widely measured of all plant functional traits. In deciduous forests, there is similarity between plastic and evolutionary responses of LMA to light gradients. In evergreens, however, LMA is lower in shaded than sunlit individuals of the same species, whereas shade-tolerant evergreens have higher LMA than light-demanders grown under the same conditions. We suggest that this pattern of ‘counter- gradient variation’ results from some combination of (i) close evolutionary coordination of LMA with leaf lifespan, (ii) selection for different leaf constitutions (relative investment in cell walls versus cell contents)in sun and shade environments and/or (iii) constraints on plasticity as a result of genetic correlations between phenotypes expressed in sun and shade.
AB - Leaf mass per area (LMA) is one of the most widely measured of all plant functional traits. In deciduous forests, there is similarity between plastic and evolutionary responses of LMA to light gradients. In evergreens, however, LMA is lower in shaded than sunlit individuals of the same species, whereas shade-tolerant evergreens have higher LMA than light-demanders grown under the same conditions. We suggest that this pattern of ‘counter- gradient variation’ results from some combination of (i) close evolutionary coordination of LMA with leaf lifespan, (ii) selection for different leaf constitutions (relative investment in cell walls versus cell contents)in sun and shade environments and/or (iii) constraints on plasticity as a result of genetic correlations between phenotypes expressed in sun and shade.
KW - leaves
KW - shade
UR - http://handle.uws.edu.au:8081/1959.7/506180
M3 - Article
SN - 0169-5347
VL - 23
SP - 299
EP - 303
JO - Trends in Ecology and Evolution
JF - Trends in Ecology and Evolution
IS - 6
ER -