Fossil evidence for Cretaceous escalation in angiosperm leaf vein evolution

Feild, Taylor S., Brodribb, Timothy J., Iglesias, Ari, Chatelet, David S., Baresch, Andres, Upchurch, Garland R., Gomez, Bernard, Mohr, Barbara A.R., Coiffard, Clement, Kvacek, Jiri, and Jaramillo, Carlos (2011) Fossil evidence for Cretaceous escalation in angiosperm leaf vein evolution. Proceedings of the National Academy of Sciences of the United States of America, 108 (20). pp. 8363-8366.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1073/pnas.101445610...
135


Abstract

The flowering plants that dominate modern vegetation possess leaf gas exchange potentials that far exceed those of all other living or extinct plants. The great divide in maximal ability to exchange CO(2) for water between leaves of nonangiosperms and angiosperms forms the mechanistic foundation for speculation about how angiosperms drove sweeping ecological and biogeo-chemical change during the Cretaceous. However, there is no empirical evidence that angiosperms evolved highly photosynthetically active leaves during the Cretaceous. Using vein density (D(V)) measurements of fossil angiosperm leaves, we show that the leaf hydraulic capacities of angiosperms escalated several-fold during the Cretaceous. During the first 30 million years of angiosperm leaf evolution, angiosperm leaves exhibited uniformly low vein D(V) that overlapped the D(V) range of dominant Early Cretaceous ferns and gymnosperms. Fossil angiosperm vein densities reveal a subsequent biphasic increase in D(V). During the first mid-Cretaceous surge, angiosperm D(V) first surpassed the upper bound of D(V) limits for nonangiosperms. However, the upper limits of D(V) typical of modern megathermal rainforest trees first appear during a second wave of increased D(V) during the Cretaceous-Tertiary transition. Thus, our findings provide fossil evidence for the hypothesis that significant ecosystem change brought about by angiosperms lagged behind the Early Cretaceous taxonomic diversification of angiosperms.

Item ID: 35656
Item Type: Article (Research - C1)
ISSN: 1091-6490
Keywords: angiosperm evolution, plant evolution, transpiration, tropical rainforest, venation
Funders: National Science Foundation (USA), Consejo Nacional de Investigaciones Científicas y Técnicas
Projects and Grants: NSF ( DEB-0919071, IOB-0714156)
Date Deposited: 01 Oct 2014 15:56
FoR Codes: 06 BIOLOGICAL SCIENCES > 0607 Plant Biology > 060705 Plant Physiology @ 100%
SEO Codes: 97 EXPANDING KNOWLEDGE > 970106 Expanding Knowledge in the Biological Sciences @ 100%
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page