MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
Sensitivity of leaf size and shape to climate: global patterns and paleoclimatic applications
DANIEL J. PEPPE; DANA L. ROYER; BÁRBARA CARIGLINO; FABIANY HERRERA; ELLEN D. CURRANO; LUIS FELIPE HINOJOSA; ARI IGLESIAS; CARLOS A. JARAMILLO; KIRK JOHNSON
WILEY-BLACKWELL PUBLISHING, INC
Año: 2011 vol. 190 p. 724 - 724
? Paleobotanists have long used models based on leaf size and shape to reconstructpaleoclimate. However, most models incorporate a single variable or usetraits that are not physiologically or functionally linked to climate, limiting theirpredictive power. Further, they often underestimate paleotemperature relative toother proxies.? Here we quantify leaf?climate correlations from 92 globally distributed, climaticallydiverse sites, and explore potential confounding factors. Multiple linearregression models for mean annual temperature (MAT) and mean annual precipitation(MAP) are developed and applied to nine well-studied fossil floras.? We find that leaves in cold climates typically have larger, more numerous teeth,and are more highly dissected. Leaf habit (deciduous vs evergreen), local wateravailability, and phylogenetic history all affect these relationships. Leaves in wetclimates are larger and have fewer, smaller teeth. Our multivariate MAT and MAPmodels offer moderate improvements in precision over univariate approaches(± 4.0 vs 4.8ºC for MAT) and strong improvements in accuracy. For example, ourprovisional MAT estimates for most North American fossil floras are considerablywarmer and in better agreement with independent paleoclimate evidence.? Our study demonstrates that the inclusion of additional leaf traits that are functionallylinked to climate improves paleoclimate reconstructions. This work alsoillustrates the need for better understanding of the impact of phylogeny and leafhabit on leaf?climate relationships.