Flammable biomes dominated by eucalypts originated at the Cretaceous-Palaeogene boundary

Nat Commun. 2011 Feb 15:2:193. doi: 10.1038/ncomms1191.

Abstract

Fire is a major modifier of communities, but the evolutionary origins of its prevalent role in shaping current biomes are uncertain. Australia is among the most fire-prone continents, with most of the landmass occupied by the fire-dependent sclerophyll and savanna biomes. In contrast to biomes with similar climates in other continents, Australia has a tree flora dominated by a single genus, Eucalyptus, and related Myrtaceae. A unique mechanism in Myrtaceae for enduring and recovering from fire damage likely resulted in this dominance. Here, we find a conserved phylogenetic relationship between post-fire resprouting (epicormic) anatomy and biome evolution, dating from 60 to 62 Ma, in the earliest Palaeogene. Thus, fire-dependent communities likely existed 50 million years earlier than previously thought. We predict that epicormic resprouting could make eucalypt forests and woodlands an excellent long-term carbon bank for reducing atmospheric CO(2) compared with biomes with similar fire regimes in other continents.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Bayes Theorem
  • Biological Evolution*
  • Computational Biology
  • DNA, Ribosomal Spacer / genetics
  • Ecosystem*
  • Fires*
  • Models, Genetic
  • Myrtaceae / anatomy & histology
  • Myrtaceae / genetics
  • Myrtaceae / physiology*
  • Paleontology
  • Phylogeny*
  • Plant Stems / anatomy & histology
  • Plant Stems / growth & development
  • Sequence Alignment
  • Sequence Analysis, DNA

Substances

  • DNA, Ribosomal Spacer