Abstract Detail

Ecology

Turck, Daniel [1], Harmon, Luke [2], Tank, David [3].

Fire in the Tree: The Origin and Distribution of Fire Adapted Traits within Conifers and their Influence on Speciation Rates across the Conifer Phylogeny.

Fire as a disturbance has been affecting plant ecosystems since at least the Silurian. Many plant species possess traits, which increase their fitness in the face of specific fire regimes. There is evidence that clades rich in fire adapted traits have higher rates of diversification than those without. Conifers are one of the older plant lineages to be affected by fire, with Pinaceae having evolved fire adaptations in the Cretaceous. The Coniferae clade has four fire adaptations present in its phylogeny: thick insulating bark, serotinous cones, seedling grass stage, and the ability to resprout foliage post fire. Given the presence of identical fire adapted traits, as well as speciose and species depauperate clades, we sought to determine when adaptations arose across the whole conifer phylogeny and establish if these traits are tied to elevated diversification rates. Using a combination of ancestral state reconstructions, as well as diversification rate simulations, we were able to ascertain the timing of fire adaptations and differing speciation rates across Araucariaceae, Cupressaceae, Pinaceae, Podocarpaceae, and Taxaceae. Our results indicate numerous convergent evolutionary events within conifers coinciding with the emergence of novel fire regimes in the Cretaceous, Paleogene, and Neogene. However, we find no evidence linking fire adaptations to increased diversification rates within the conifer clade.

1 - University of Idaho, Department of Biological Sciences, 503 E D Street, Moscow, ID, 83843, United States
2 - University of Idaho, Department of Biological Sciences, 875 Perimeter Drive MS 3051, Moscow, Idaho, 83844, United States
3 - University Of Idaho, Department Of Biological Sciences, 600 Ridge Rd., Moscow, ID, 83843, United States

Keywords:
conifers
Fire Adaptations
Thick Bark
Serotinous Cones
Seedling Grass Stage
Resprouting.

Presentation Type: Oral Paper
Session: ECO1, Ecology: Phylogeny, Disturbance, and Tree Architecture Over Large Spatial Scales
Location: /
Date: Tuesday, July 20th, 2021
Time: 10:45 AM(EDT)
Number: ECO1004
Abstract ID:277
Candidate for Awards:Ecological Section Best Graduate Student Paper