The Edwards Lab



The "Portullugo" is a clade of ~2200 species that live in a wide variety of habitats and are found on every continent, though they have a penchant for deserts and the high alpine (lucky us). The lineage includes well known groups such as the cacti, and less famous but equally wonderful plants like the Molluginaceae, the purslanes, lewisias, and the Didiereaceae.

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We are especially interested in how C4 and CAM photosynthesis, two fairly complicated plant adaptations to low CO2, hot temperatures, and drought, have evolved so many times (~100s), mostly over the past 15 or so million years. We have worked on the C4 problem in grasses and are currently focusing our attention on C4 and CAM origins in the Portullugo, a lineage that holds a suprising number of both C4 and CAM plants.


Viburnum is a clade of ~165 species of woody shrubs and trees common in northern hemisphere forests, but they are also found in tropical Asia and montane forests throughout Central and South America. We are currently focused on using this lineage to study the evolution of leaf form and function, and in tropical-temperate biome transitions, but in reality we are pretty interested in every single thing about Viburnum.

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Edwards Lab Members

Edwards lab members, past and present.

Erika Edwards

Erika Edwards

Principal Investigator

Pauline Raimondeau

Pauline Raimondeau

YIBS Hutchinson Postdoc Fellow

Shawn Abrahams

Shawn Abrahams

NSF Plant Genome Postdoc Fellow

Anri Chomentowska

Anri Chomentowska

Graduate Student

Oluwatobi Oso

Oluwatobi Oso

Graduate Student

Lan Wei

Lan Wei

Graduate Student

Ana Betancourt

Ana Betancourt

Post-bac research fellow

Alison Carranza

Alison Carranza

Post-bac research fellow

Ellie Jose

Ellie Jose

Post-bac research fellow



Research Assistant



Research Assistant

Lab Alums:

Carlos Maya-Lastra, post-doc (2022-2023)

Jose Moreno-Villena, post-doc (2018-2022)

Haoran Zhou, post-doc (2019-2021)

Anthony Baniaga, post-doc (2019-2021)

Karolina Heyduk, post-doc (2018-2019)

Eric Goolsby, post-doc (2016-2018)

Zachary Lewis, post-doc (2016-2017)

Abigail Moore, post-doc (2013-2016)

Jurriaan de Vos, post-doc (2013-2015)

David Chatelet, post-doc (2010-2015)

Radika Bhaskar, post-doc (2011-2014)

Pascal-Antoine Christin, post-doc (2010-2012)

Monica Arakaki, post-doc (2009-2012)

Ian Gilman, grad student(2017-2023)

Josh Randall, grad student (2020-2023)

Morgan Moeglein, grad student (2014-2021)

Lillian Hancock, grad student (2012-2017)

Laura Garrison, grad student (2010-2016)

Matt Ogburn, grad student (2007-2012)

Nora Heaphy, undergrad and research technician (2020-2022)

Anthony Sarkiss, undergrad (2019-2021)

Haley Carter, undergrad (2014-2017)

Eric Kelosa-Kenyon, undergrad (2013-2015)

Regan Lichtenberg, undergrad (2013-2015)

Arisa Lohmeier, undergrad (2012-2014)

Joel Abraham, research technician (2018-2019)

Elizabeth Spriggs, undergrad and research technician (2008-2012)

Asya Rahlin, undergrad (2011-2012)

Alejandro Brambila, undergrad (2011-2012)

Sam Schmerler, undergrad (2008-2011)

Anne Williard, undergrad (2008-2009)

Cassidy Metcalf, undergrad (2007-2008)

Elissa Martin, research tech (2017-2018)

Kaya Schmandt, research tech (2008-2010)

Creature Cast

Our plant-y contributions to the Dunn Lab's creaturecast website. Animations about weird and beautiful plant life, (mostly) created by Brown undergrads enrolled in Bio43. All animations created under a creative commons license and freely available to use in any educational setting.


Sage RF, IS Gilman, JAC Smith, K Silvera, EJ Edwards. 2023. Atmospheric CO2 decline and the timing of CAM plant evolution. Invited review for Annals of Botany 132: 753-770.

Edwards EJ. 2023. Reconciling continuous and discrete models of C4 and CAM evolution. Invited review for Annals of Botany 132: 717-725.

Gilman IS, JAC Smith, JA Holtum, RW Sage, K Winter, EJ Edwards. 2023. The CAM lineages of planet Earth. Invited review for Annals of Botany 132: 627-654.

Sage RF, EJ Edwards, K Heyduk, JC Cushman. 2023. Crassulacean Acid Metabolism (CAM) at the crossroads: a special issue in the Annals of Botany to honor 50 years of CAM research by Klaus Winter. Annals of Botany 132: 553-561.

Donoghue MJ, DA Eaton, CA Maya-Lastra, MJ Landis, PW Sweeney, ME Olson, NI Cacho, MK Moeglein, JR Gardner, NM Heaphy, M Castorena, A Segovia Rivas, WL Clement, EJ Edwards. 2022. Replicated radiation of a plant clade along a cloud forest archipelago. Nature Ecology and Evolution 6: 1318-1329.

Moreno Villena JJ, H Zhou, I Gilman, L Tausta, M Cheung, EJ Edwards. 2022. Spatial resolution of an integrated C4+CAM photosynthetic metabolism. Science Advances 8, eabn2349.

Gilman IS, JJ Moreno Villena, ZR Lewis, EW Goolsby, EJ Edwards. 2022. Gene co-expression reveals the modularity and integration of C4 and CAM in Portulaca. Plant Physiology 189: 735-753.

Donoghue MJ, EJ Edwards. 2022. Clade biology, phylogenetic biology, and systematics. Plant Science Bulletin 68: 7-11.

Holtum JAH, L Hancock, EJ Edwards, K Winter. 2021. CAM photosynthesis in desert blooming Cistanthe of the Atacama, Chile. Functional Plant Biology 48: 691-702

Baird AS, SH Taylor, J Pasquet-Kok, C Vuong, Y Zhang, T Watcharamongkol, C Scoffoni, EJ Edwards, PA Christin, CP Osborne, L Sack. 2021. Developmental basis for the worldwide climatic distribution of grass leaf size. Nature 592: 242-247

Landis MJ, EJ Edwards, MJ Donoghue. 2021. Modeling phylogenetic biome shifts on a planet with a past. Systematic Biology 70: 86-107

Landis MJ, DAR Eaton, WL Clement, B Park, EL Spriggs, PW Sweeney, EJ Edwards, MJ Donoghue. 2021. Joint phylogenetic estimation of geographic movements and biome shifts during the global diversification of Viburnum. Systematic Biology 70: 67-85

Moeglein MK, D Chatelet, MJ Donoghue, EJ Edwards. 2020. Evolutionary dynamics of genome size in a clade of woody plants. American Journal of Botany 107: 1527-1541

Griffith D, C Osborne, EJ Edwards, S Bachle, D Beerling, W Bond, T Gallaher, B Helliker, C Lehmann, L Leatherman, J Nippert, S Pau, F Qiu, W Riley, M Smith, C Stromberg, L Taylor, M Ungerer, CJ Still. 2020. Lineage functional types (LFTs): characterizing functional diversity to enhance the representation of ecological behavior in Earth Systems models. New Phytologist 228: 15-23

Nurk, N, P Linder, R Onstein, M Larcombe, C Hughes, L Fernandez, P Schluter, L Valente, C Beierkuhnlein, V Cutts, MJ Donoghue, EJ Edwards, R Field, S Flantua, S Higgins, A Jentsch, S Liede-Schumann, MD Pirie. 2020. Diversification in evolutionary arenas- assessment and synthesis. Ecology and Evolution 10: 6163-6182

Gilman I, EJ Edwards. CAM Photosynthesis. 2020. Current Biology 30: R57-R62

Ferrari RC, PP Bittencourt, MA Rodrigues, JJ Moreno-Villena, FRR Alves, VD Gastaldi, SF Boxall, LV Dever, D Demarco, SCS Andrade, EJ Edwards, J Hartwell, L Freschi. 2020. C4 and crassulacean acid metabolism photosynthesis within a single leaf: deciphering key components behind a rare photosynthetic adaptation. New Phytologist 225: 1699-1714

Ogburn RM, EJ Edwards. 2019. Celebrating a new Division of Botany at SICB: An introduction to the Integrative Plant Biology symposium. Integrative and Comparative Biology 59: 489-492

Hancock LP, JAM Holtum, EJ Edwards. 2019. The evolution of CAM photosynthesis in Australian Calandrinia reveals lability in C3+CAM phenotypes and a possible constraint to the evolution of strong CAM. Journal of Integrative and Comparative Biology 59: 517-534

Winter K, RF Sage, EJ Edwards, A Virgo, JAM Holtum. 2019. Facultative CAM in a C3-C4 intermediate. Journal of Experimental Botany 70: 6571-6579

Edwards EJ. 2019. Evolutionary trajectories, accessibility, and other metaphors: the case of C4 and CAM photosynthesis. Tansley Review, New Phytologist 223: 1742-1755

Spriggs EL, C Schlutius, DAR Eaton, B Park, P Sweeney, EJ Edwards, MJ Donoghue. 2019. Differences in flowering time maintain species boundaries in a continental radiation of Viburnum. American Journal of Botany 106: 833-849

Heyduk K, JJ Moreno-Villena, I Gilman, PA Christin, EJ Edwards. 2019. The genetics of convergent evolution: insights from plant photosynthesis. Nature Reviews Genetics 20: 485-493

Donoghue MJ, EJ Edwards. 2019. Model clades are vital for comparative biology, and ascertainment bias is not a problem in practice – a response to Beaulieu and O’Meara. American Journal of Botany 106: 327-330

Spriggs EL, DAR Eaton, PW Sweeney, C Schlutiusgg, EJ Edwards, MJ Donoghue. 2019. RADSeq data reveal a cryptic Viburnum species on the North American coastal plain. Systematic Biology 68: 187-203

Thiele KR, F Obbens, L Hancock, EJ Edwards, JG West. 2018. Proposal to conserve the name Parakeelya against Rumicastrum (Montiaceae). Taxon 67: 214-215

Olson ME, D Soriano, JA Rosell, T Anfodillo, MJ Donoghue, EJ Edwards, C Leon-Gomez, T Dawson, JJ Martinez, M Castorena, A Echeverria, CI Espinosa, A Fajardo, A Gazol, S Isnard, RS Lima, CR Marcati, R Mendz-Alonzo. 2018. Plant height and hydraulic vulnerability to drought and cold. Proceedings of the National Academy of Sciences USA 115: 7551-7556

Thulin M, A Larsson, EJ Edwards, AJ Moore. 2018. Phylogeny and systematics of Kewa (Kewaceae). Systematic Botany 43: 689-700

Hancock LP, F Obbens, AJ Moore, K Thiele, JM de Vos, J West, JAM Holtum, EJ Edwards. 2018. Phylogeny, evolution, and biogeographic history of Calandrinia (Montiaceae). American Journal of Botany 105: 1021-1034

Li M, H An, R Angelovici, C Bagaza, A Batushansky, L Clark, V Coneva, MJ Donoghue, EJ Edwards, D Fajardo, H Fang, MH Frank, T Gallaher, S Gebken, T Hill, S Jansky, B Kaur, PC Klahs, LL Klein, V Kuraparthy, J Londo, Z Migicovsky, A Miller, R Mohn, S Myles, CN Topp, A Van Deynze, K Zhang, L Zhu, BM Zink, DH Chitwood. 2018. Topological data analysis as a morphometric method: using persistent homology to demarcate a leaf morphospace. Frontiers in Plant Science 9:553

Goolsby EW, AJ Moore, LP Hancock, JM de Vos, EJ Edwards. 2018. Molecular evolution of key metabolic genes during transitions to C4 and CAM photosynthesis. American Journal of Botany 105: 602-613

Spriggs EL, S Schmerler, EJ Edwards, MJ Donoghue. 2018. Leaf form varies along a shared axis across multiple scales in Viburnum. American Naturalist 191: 235-249

Moore AJ, JM de Vos, LP Hancock, E Goolsby, EJ Edwards. 2018. Targeted enrichment of large gene families for phylogenetic inference: phylogeny and molecular evolution of photosynthesis genes in the portullugo (Caryophyllales). Systematic Biology 67: 367-383

Holtum JAM, LP Hancock, EJ Edwards, K Winter. 2018. Crassulacean Acid Metabolism (CAM) in the Basellaceae (Caryophyllales). Plant Biology 20: 409-414

Holtum JAM, LP Hancock, EJ Edwards, K Winter. 2017. Facultative CAM photosynthesis in four species of Calandrinia, ephemeral succulents of arid Australia. Photosynthesis Research 134: 17-25

Edwards EJ, DS Chatelet, B Chen, JY Ong, S Tagane, J Kanemitsu, K Tagawa, K Teramoto, B Park, KF Chung, JM Hu, T Yahara, MJ Donoghue. 2017. Convergence, consilience, and the evolution of temperate deciduous forests. American Naturalist 190: S87-S104

Obbens FJ, LP Hancock, EJ Edwards, KR Thiele. 2017. Calandrinia holtumii (Montiaceae), a new and unusual species from arid Western Australia. Nuytsia 28: 217-233

Dunning L, JJ Moreno-Villena, MR Lundgren, A Brautigam, EJ Edwards, P Nosil, CP Osborne, PA Christin. 2017. Reticulate evolution facilitated the recurrent emergence of C4 photosynthesis within closely related species. Evolution 71: 1541-1555

Holtum JAM, LP Hancock, EJ Edwards, K Winter. 2017. Optional use of CAM photosynthesis in two C4 species, Portulaca cyclophylla and Portulaca dignya. Journal of Plant Physiology 214: 91-96

Edwards EJ, DS Chatelet, EL Spriggs, ES Johnson, C Schlutius, MJ Donoghue. 2017. Correlation, causation, and the evolution of leaf teeth: A reply to Givnish and Kriebel. American Journal of Botany 104: 509-515

Forrestel EJ, MJ Donoghue, EJ Edwards, W Jetz, JCO du Toit, MD Smith. 2017. Different clades and traits yield similar grassland functional responses. Proceedings of the National Academy of Sciences 114: 705-710

Barish S, M Arakaki, EJ Edwards, MJ Donoghue, WL Clement. 2016. Characterization of 16 microsatellite markers for the Oreinotinus clade of Viburnum (Adoxaceae). Applications in Plant Sciences 4: 1600103

Thulin M, AJ Moore, H El-Seedi, A Larsson, PA Christin, EJ Edwards. 2016. Phylogeny and generic delimitation in Molluginaceae, new pigment data in Caryophyllales, and the new family Corbichoniaceae. Taxon 65: 775-793

Edwards EJ, EL Spriggs, D Chatelet, MJ Donoghue. 2016. Unpacking a century old mystery: winter buds and the latitudinal gradient in leaf form. American Journal of Botany 103: 975-978

Scoffoni C, D Chatelet, J Pasquet-Kok, M Rawls, MJ Donoghue, EJ Edwards, L Sack. 2016. Hydraulic basis for the evolution of photosynthetic productivity. Nature Plants 2: 16072

Bhaskar R, S Porder, P Balvanera, EJ Edwards. 2016. Ecological and evolutionary variation in community nitrogen use traits during tropical dry forest secondary succession. Ecology 97: 1194-1206

Holtum JAC, L Hancock, EJ Edwards, M Crisp, D Crayn, R Sage, K Winter. 2016. Australia lacks stem succulents but is it depauperate in plants with Crassulacean Acid Metabolism (CAM)? Current Opinion in Plant Biology 31: 109-117

Ogburn RM, EJ Edwards. 2015. Life history lability underlies rapid climate niche evolution in the angiosperm clade Montiaceae. Molecular Phylogenetics and Evolution 92: 181-192

Yang X, JC Cushman, AM Borland, EJ Edwards, and 47 others. 2015. A roadmap for research on crassulacean acid metabolism (CAM) to enhance sustainable food and bioenergy production in a hotter, drier world. New Phytologist 207: 491-504

Edwards EJ, JM de Vos, MJ Donoghue. 2015. Brief Communications Arising: Doubtful pathways to cold tolerance in plants. Nature 521, doi:10.1038/nature14393

Spriggs EA, WL Clement, PW Sweeney, S Madrinan, EJ Edwards, MJ Donoghue. 2015. Temperate radiations and dying embers of a tropical past: the diversification of Viburnum. New Phytologist 207: 340-354

Christin PA, M Arakaki, CP Osborne, EJ Edwards. 2015. Genetic enablers underlying the clustered evolutionary origins of C4 photosynthesis in angiosperms. Molecular Biology and Evolution 32: 846-858

Donoghue MJ, EJ Edwards. 2014. Biome shifts and niche evolution in plants. Annual Review of Ecology, Evolution, and Systematics 45: 547-572

Gao L, EJ Edwards, Y Zeng, Y Huang. 2014. Major evolutionary trends in hydrogen isotope fractionation of vascular plant leaf waxes. PLoS ONE 9(11): e112610

Edwards EJ. 2014. The inevitability of C4 photosynthesis. eLife 3:e03702

Howison M, F Zapata, EJ Edwards, CW Dunn. 2014. Bayesian genome assembly and assessment by markov chain monte carlo sampling. PLoS ONE 9(6): e99497

Clement WL, M Arakaki, PW Sweeney, EJ Edwards, MJ Donoghue. 2014. A chloroplast tree for Viburnum and its implications for phylogenetic classification and character evolution. American Journal of Botany 101: 1029-1049

Christin PA, M Arakaki, CP Osborne, A Brautigam, RF Sage, JM Hibberd, S Kelly, S Covshoff, GKS Wong, L Hancock, EJ Edwards. 2014. Shared origins of a key enzyme during the evolution of C4 and CAM metabolism. Journal of Experimental Botany 65: 3609-3621

Hancock L, EJ Edwards. 2014. Phylogeny and the inference of evolutionary trajectories. Journal of Experimental Botany 65: 3491-3498

Spriggs EL, PA Christin, EJ Edwards. 2014. C4 photosynthesis promoted species diversification during the Miocene grassland expansion. PLoS ONE 9(5):e97722

Edwards EJ, DS Chatelet, L Sack, MJ Donoghue. 2014. Leaf life span and the leaf economic spectrum in the context of whole plant architecture. Journal of Ecology 102: 328-336

Christin PA, E Spriggs, CP Osborne, CAE Stromberg, N Salamin, EJ Edwards. 2014. Molecular dating, evolutionary rates, and the age of the grasses. Systematic Biology 63: 153-165

Still CJ, S Pau, EJ Edwards. 2014. Land surface skin temperature captures thermal environments of C3 and C4 grasses. Global Ecology and Biogeography 23: 286-296

Christin PA, SF Boxall, R Gregory, EJ Edwards, J Hartwell, CP Osborne. 2013. Parallel recruitment of multiple genes into C4 photosynthesis. Genome Biology and Evolution 5: 2174-2187

Chatelet DS, WL Clement, L Sack, MJ Donoghue, EJ Edwards. 2013. The evolution of photosynthetic anatomy in Viburnum (Adoxaceae). International Journal of Plant Sciences 174: 1277-1291

Edwards EJ, MJ Donoghue. 2013. Is it easy to move and easy to evolve? Evolutionary accessibility and adaptation. Journal of Experimental Botany 64: 4047-4052

Ogburn RM, EJ Edwards. 2013. Repeated origin of three-dimensional leaf venation releases constraints on the evolution of succulence in plants. Current Biology 23: 722-726

Christin, PA, CP Osborne, DS Chatelet, JT Columbus, G Besnard, TR Hodkinson, LM Garrison, MS Vorontsova, EJ Edwards. 2013. Anatomical enablers and the evolution of C4 photosynthesis in grasses. Proceedings of the National Academy of Sciences USA 110: 1381-1386

Pau S, EJ Edwards, CS Still. 2013. Improving our understanding of environmental controls on the distribution of C3 and C4 grasses. Global Change Biology 19: 184-196

Christin PA, MJ Wallace, H Clayton, EJ Edwards, RT Furbank, PW Hattersley, RF Sage, TD Macfarlane, M Ludwig. 2012. Multiple photosynthetic transitions, polyploidy, and lateral gene transfer in the grass subtribe Neurachninae. Journal of Experimental Botany 63: 6297-6308

Schmerler S, W Clement, J Beaulieu, D Chatelet, L Sack, MJ Donoghue, EJ Edwards. 2012. Evolution of leaf form correlates with temperate/tropical transitions in Viburnum. Proceedings of the Royal Society of London B: Biological Sciences 279: 3905-3913

Liu H, EJ Edwards, R Freckleton, CP Osborne. 2012. Phylogenetic niche conservatism in C4 grasses. Oecologia 170: 835-845

Ogburn RM, EJ Edwards. 2012. Quantifying succulence: a rapid, physiologically meaningful measure of plant water storage. Plant, Cell and Environment 35: 1533-1542

Feild T, EJ Edwards. 2012. Celebrating giant steps toward a synthetic history of angiosperm evolution. Special issue of International Journal of Plant Sciences 173: 599-560

Edwards EJ, RM Ogburn. 2012. Angiosperm responses to a low CO2 world: CAM and C4 photosynthesis as parallel evolutionary trajectories. Special issue of International Journal of Plant Sciences 173: 724-733

Christin PA, EJ Edwards, G Besnard, SF Boxall, R Gregory, EA Kellogg, J Hartwell, CP Osborne. 2012. Adaptive evolution of C4 photosynthesis through recurrent lateral gene transfer. Current Biology 22: 445-449

Christin PA, G Besnard, EJ Edwards, N Salamin. 2012. Effect of genetic convergence on phylogenetic inference. Molecular Phylogenetics and Evolution 62: 921-927

Grass Phylogeny Working Group II. 2012. New grass phylogeny resolves deep evolutionary relationships and discovers C4 origins. New Phytologist 193: 304-312

Taylor SH, PJ Franks, SP Hulme, E Spriggs, PA Christin, EJ Edwards, FI Woodward, CP Osborne. 2012. Photosynthetic pathway and ecologial adaptation explain stomatal trait diversity amongst grasses. New Phytologist 193: 387-396

Sage RF, PA Christin, EJ Edwards. 2011. C4 plant lineages of planet Earth. Special issue of Journal of Experimental Botany 62: 3155-3169

Christin, PA, CP Osborne, RF Sage, M Arakaki, EJ Edwards. 2011. C4 eudicots are not younger than C4 monocots. Special issue of Journal of Experimental Botany 62: 3171-3181

Arakaki M, PA Christin, A Lendel, R Nyffeler, U Eggli, RM Ogburn, E Spriggs, M Moore, EJ Edwards. 2011. Recent and contemporaneous radiations of the worlds succulent plant lineages. Proceedings of the National Academy of Sciences USA 108: 8379-8384

Christin PA, T Sage, EJ Edwards, RM Ogburn, R Khoshravish, RF Sage. 2011. Complex evolutionary transitions and the significance of C3-C4 intermediate forms of photosynthesis in Molluginaceae. Evolution 65: 643-660

Ogburn RM, EJ Edwards. 2010. The ecological water-use strategies of succulent plants. invited review, Advances in Botanical Research 55: 179-255

Davis CC, EJ Edwards, MJ Donoghue. 2010. A clade's eye view of global climate change. in M. A. Bell, D. J. Futuyma, W. F. Eanes, and J. S. Levinton, eds. Evolution since Darwin: the first 150 years. pp. 623-627. Sinauer, Sunderland, Massachusetts

Edwards EJ*, CO Osborne*, CAE Stromberg*, SA Smith and the C4 Grasses Consortium. 2010. The origins of C4 grasslands: integrating evolutionary and ecosystem science. Science 328: 587-591

Edwards EJ, SA Smith. 2010. Phylogenetic analyses reveal the shady history of C4 grasses. Proceedings of the National Academy of Sciences USA 107: 2532-2537

Cellinese N, SA Smith, EJ Edwards, ST Kim, RC Haberle, MJ Donoghue. 2009. Historical biogeography of the endemic Campanulaceae of Crete. Journal of Biogeography 36: 1253-1269

Ogburn RM and EJ Edwards. 2009. Anatomical variation in the closest relatives of cacti: trait lability and evolutionary innovation. American Journal of Botany 96: 391-408

Nyffeler R, U Eggli, RM Ogburn, EJ Edwards. 2008. Variations on a theme: repeated evolution of succulent life forms in the Portulacineae. invited paper, Haseltonia 14: 26-36

Butterworth CA, EJ Edwards. 2008. Investigating Pereskia and the earliest divergences in Cactaceae. invited paper, Haseltonia 14: 46-53

Edwards EJ, CJ Still. 2008. Climate, phylogeny and the ecological distribution of C4 grasses. Ecology Letters 11: 266-276

Edwards EJ, CJ Still, MJ Donoghue. 2007. The relevance of phylogeny to studies of global climate change. Trends in Ecology and Evolution 22: 243-249

Edwards EJ. 2006. Correlated evolution of stem and leaf hydraulic traits in Pereskia (Cactaceae). New Phytologist 172: 479-489

Edwards EJ, MJ Donoghue. 2006. Pereskia and the origin of the cactus life form. American Naturalist 167: 777-793

Edwards EJ, M Diaz. 2006. Ecological physiology of Pereskia guamacho, a cactus with leaves. Plant Cell and Environment 29: 247-256

Riedel SM, EH Epstein, DA Walker, DL Richardson, MP Calef, EJ Edwards, A Moody. 2005. Spatial and temporal heterogeneity of vegetation properties among four tundra plant communities at Ivotuk, Alaska, USA. Arctic, Antarctic, and Alpine Research 37: 25-33

Edwards EJ, R Nyffeler, MJ Donoghue. 2005. Basal cactus phylogeny: implications of Pereskia paraphyly for the transition to the cactus life form. American Journal of Botany 92 (7): 1177-1188

Brodribb TJ, NM Holbrook, EJ Edwards, MV Gutierrez. 2003. Relations between stomatal closure, leaf turgor and xylem vulnerability in eight tropical dry forest trees. Plant Cell and Environment 26: 443-450

Bell CD, EJ Edwards, ST Kim, MJ Donoghue. 2001. Dipsacales phylogeny based on chloroplast DNA sequences. Harvard Papers in Botany 6: 481-499