Abstract Detail

Innovation and Novelty in the Evolution of Plants

Stull, Gregory [1], Walker-Hale, Nathanael [2], Maeda, Hiroshi [3], Yang, Ya [4], Brockington, Samuel [5], Smith, Stephen [6].

Placing the origins of phenotypic novelties in Caryophyllales in a geologic and evolutionary context.

While some plant lineages remain relatively stereotyped in their morphology, life history, and ecological preferences for considerable durations of geologic time, others are characterized by extraordinary diversity in these respects with a remarkable capacity to generate phenotypic novelties alongside extreme shifts in ecological setting. The Carophyllales are an unrivaled example of the latter, with representatives tolerant of extremes in heat, cold, drought, elevation, and salinity and showing an array of remarkable phenotypic features including succulence, betalain pigments, alternative photosynthetic pathways (C4, CAM), huge variation in androecial patterns, and carnivory. Some of these novelties/innovations have repeated origins in the order and some as well are only found in Caryophyllales. Placing the origins of these functionally significant traits in a firm geologic context—though critical for fully understanding their evolutionary and ecological significance—has been made difficult by the generally poor fossil record of Carophyllales, a consequence of many lineages occurring predominantly in non-depositional environments. However, based on a critical survey of the fossil literature of Carophyllales, we have amassed an appreciable number of reliable fossil occurrences (especially pollen) spanning the phylogenetic breadth of the order and ranging in geologic time from Late Cretaceous to the present. We leverage these fossil data to examine spatial/temporal patterns of fossil occurrences and to reconstruct divergence times across the order. We then use this dated tree to reconstruct the temporal origins of major novelties, which we relate to geologic history as well as broader patterns in phenotypic rates, disparification, genomic conflict, and polyploidization. Through this synthesis we aim to better understanding the intrinsic and extrinsic factors that facilitate the origins of phenotypic novelties in plants.

1 - National Museum of Natural History, Department of Botany, Washington, DC, 20013, USA
2 - University Of Cambridge, Department Of Plant Sciences, Downing Street, Cambridge, CAM, CB23EA, United Kingdom
3 - University of Wisconsin-Madison, Department of Botany, Madison, WI, 53706, USA
4 - University of Minnesota, Plant and Microbial Biology, 1445 Gortner Ave, St Paul, MN, 55108, USA
5 - 4 Sleaford Street, Cambridge, CAM, CB12PW, United Kingdom
6 - University of Michigan, Ecology and Evolutionary Biology, 1105 N University Ave, Ann Arbor, MI, 48109

Keywords:
betalains
Carophyllales
Fossils
innovation
novelty
paleobotany
trait evolution.

Presentation Type: Colloquium Presentations
Number: C6001
Abstract ID:565
Candidate for Awards:None