Abstract Detail


Chen, Yanni [1], Latvis, Maribeth [2], Perkins, Lora [3], A. Joshua, Leffler [3], Johnson, Matt [4].

The Macroevolution of a Smoke-induced Seed Germination Trait.

Smoke induced seed germination has been widely detected among distantly related angiosperm species, yet, the evolutionary mechanism is unclear. The response has been more frequently studied in fire-prone ecosystems (e.g. North America California chaparral and South Africa Western Cape & Eastern Cape fynbos), leading to the dominant hypothesis among ecologists that it represents a convergent adaptation to these environmental conditions. However, smoke-induced germination has also been reported in low-fire ecosystems, cultivated species, and is likely the result of a genetic mechanism that predates the origin of seeds. An alternative hypothesis suggests smoke induced seed germination may have evolved earlier in the evolutionary history of the angiosperms, perhaps representing an adaptation to previous fire-prone environments or exaptation to the current environment. To test between the convergence (adaptation) and deep ancestry (exaptation) hypotheses, we combine data from previously published studies with our own germination study for North American species for the first global synthesis (2000+ species) of smoke-induced seed germination in an evolutionary context. We assess the phylogenetic signal, conduct ancestral state reconstruction using both maximum likelihood and Bayesian approaches, and evaluate models of trait evolution using BISSE and HISSE. If the ancestral state reconstruction supports the convergent evolution hypothesis, the results indicate the genetic evolution of smoke response was likely regulated by more recent environmental factors.

1 - Texas Tech University, Department of Biological Sciences, 2901 Main Street, Lubbock, TX, 79409, USA
2 - South Dakota State University, Department Of Natural Resource Management, 1390 College Avenue, Box 2140B, South Dakota State University , Brookings , SD, 57007, United States
3 - South Dakota State University, Department Of Natural Resource Management, 1390 College Avenue, Box 2140B, Brookings, SD, 57007, USA
4 - Texas Tech University, Biological Sciences, 2901 Main Street, Ms3131, Lubbock, TX, 79409, United States

smoke induced seed germination
phylogenetic signal
Ancestral state reconstruction
trait evolution.

Presentation Type: Oral Paper
Number: MACRO II012
Abstract ID:698
Candidate for Awards:None

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