Academic Appointments

Administrative Appointments

  • Chair, Geological Sciences/Earth & Planetary Sciences, Stanford University (2020 - 2023)
  • Professor (by courtesy), Biological Sciences, Stanford University (2019 - Present)
  • Professor, Geological Sciences, Stanford University (2018 - Present)
  • Associate professor, Stanford University (2013 - 2018)
  • Associate professor, University of Chicago (2010 - 2013)
  • Assistant professor, University of Chicago (2003 - 2010)
  • National Research Council associate, NASA Astrobiology Institute (2001 - 2003)

Honors & Awards

  • Phillips Lecture in Paleoscience, University of Illinois Urbana-Champaign (2022)
  • Klepser Distinguished Lectureship, University of Tennessee (2015)
  • Fellow, MacArthur Foundation (2013-2018)
  • W. S. Cooper Award, Ecological Society of America (2012)
  • Fellow, Paleontological Society (2011-)
  • Charles Schuchert Award, Paleontological Society (2011)
  • Postdoctoral fellowship (declined), CIW Geophysical Laboratory (2001)
  • Predoctoral fellowship, NSF (1996-1999)

Boards, Advisory Committees, Professional Organizations

  • Member, Ethics Committee, Paleontological Society (2023 - Present)
  • Editor, Paleobiology (2018 - Present)
  • Member, Fellows Committee, Paleontological Society (2017 - 2019)
  • Member, Cooper Award committee, Ecological Society of America (2014 - 2016)
  • Extended adviser, Deep Time exhibit, Smithsonian NMNH (2014 - 2015)
  • Member, Strimple Award committee, Paleontological Society (2012 - 2015)
  • Associate editor, Paleobiology (2011 - 2018)
  • Chair, Paleobotanical Section, Botanical Society of America (2006 - 2007)
  • Research associate, Geology, Field Museum of Natural History (2004 - 2014)
  • Member, Moseley Award committee, Botanical Society of America (2004 - 2006)
  • Member, Cookson Award committee, Botanical Society of America (2003 - 2003)
  • Predoctoral fellow, Geophysical Laboratory, Carnegie Institution of Washington (1999 - 2001)

Professional Education

  • Ph.D., Harvard University, Organismic & Evolutionary Biology (2001)
  • B.S., California Institute of Technology, Literature (1995)
  • B.S., California Institute of Technology, Biology (1995)

Current Research and Scholarly Interests

I focus on the initial evolution of complex multicellular life on land in the Paleozoic (542 to 250 million years ago) through the establishment of more modern ecosystems over the Mesozoic (250 to 65 million years ago). I am interested in fossils as the remnants of functioning biological organisms that can inform on the evolution of their physiology, development, and biochemistry. Those organisms preserved in the fossil record were also components of larger ecological and environmental systems and I am particularly interested in how the evolution of physiology and structure would have influenced those larger systems including carbon and other nutrient cycles as well as climate. In practice, my work involves both living and fossil organisms and a wide variety of collaborative approaches: developmental and physiological investigation, modeling of climate and the geological carbon cycle, comparative study of morphological diversity through time, and cell and tissue-specific analysis of fossil elemental, isotopic, and organic chemistry.

My science has been rooted in the plant fossil record and the particular advantages that the anatomical preservation of plant fossils provides for studying physiological and developmental evolution. Over the last decade, my work and that of my students has increasingly come to encompass the complete terrestrial biota including animals, fungi, and microbial communities. My students can expect to develop their own projects and be as much collaborator as apprentice. Applicants are welcome from both geological or biological backgrounds and with interest or expertise in any component of the terrestrial system.

2023-24 Courses

Stanford Advisees

  • Doctoral (Program)
    Seamus Callaghan

All Publications

  • Evolution of terrestrial herbivory: nutrient stoichiometry, body size, and dietary diversity FRONTIERS IN ECOLOGY AND EVOLUTION Boyce, C. 2023; 11
  • Linking host plants to damage types in the fossil record of insect herbivory PALEOBIOLOGY Schachat, S. R., Payne, J. L., Boyce, C. 2023; 49 (2): 232-258
  • Macroecological diversification of ants is linked to angiosperm evolution EVOLUTION LETTERS Nelsen, M. P., Moreau, C. S., Boyce, C., Ree, R. H. 2023: 79-87


    Ants are abundant, diverse, and occupy nearly all habitats and regions of the world. Previous work has demonstrated that ant diversification coincided with the rise of the angiosperms, and that several plant traits evolved as ants began to expand their nesting and foraging habits. In this study, we investigate whether associations with plants enabled niche expansion and are linked to climatic niche evolution in ants. Our analysis of over 1,400 ant species reveals that ancestral expansion from forest floors into the canopy and out into non-forested habitats closely followed evolutionary innovations in angiosperms. Several Paleogene-Neogene ant lineages independently diversified in non-forested habitats on multiple continents, tracking the evolution and expansion of elaiosome-bearing and arid-adapted angiosperms. The evolution of arboreal nesting tracked shifts in angiosperm physiology associated with the onset of everwet tropical rainforests, and climatic optima and rates of climatic niche evolution were linked to nesting location, with arboreally nesting groups having warmer and less seasonal climatic optima, and lower rates of climatic niche evolution. Our work further underscores the varied paths by which niche diversification occurred in ants, and how angiosperms influenced the ecological and evolutionary trajectories of interacting lineages.

    View details for DOI 10.1093/evlett/qrad008

    View details for Web of Science ID 000961078400001

    View details for PubMedID 37033878

    View details for PubMedCentralID PMC10078972

  • Illusion of flight? Absence, evidence and the age of winged insects BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY Schachat, S. R., Goldstein, P. Z., Desalle, R., Bobo, D. M., Boyce, C., Payne, J. L., Labandeira, C. C. 2022
  • What we talk about when we talk about the long-term carbon cycle. The New phytologist Boyce, C. K., Ibarra, D. E., D'Antonio, M. P. 2022


    The terrestrial biota is a crucial part of the long-term carbon cycle via the deposition of biomass as coal and other sedimentary organic matter and the impact of plants, fungi, and microbial life on the weathering of silicate minerals. Understanding these processes and their changes through time requires both geochemical modeling of the system as well as expertise in the living and fossil biotas and their ecological interactions, but details of these components are often lost in translation between disciplines. Here, we highlight misconceptions of the long-term carbon cycle that most frequently infiltrate the literature and hamper progress: mass balance requirements, the nature and duration of perturbations, opposing timescale constraints on biological and geological processes, and the role of models.

    View details for DOI 10.1111/nph.18665

    View details for PubMedID 36484141

  • The preservation of cause and effect in the rock record PALEOBIOLOGY D'Antonio, M. P., Ibarra, D. E., Boyce, C. 2022
  • Diodonopteris virgulata sp. nov., a climbing fern from the early Permian Wuda Tuff Flora and its paleoecology REVIEW OF PALAEOBOTANY AND PALYNOLOGY Zhou, W., Li, D., Psenicka, J., Boyce, C., Wang, S., Wang, J. 2022; 304
  • Nitrogen-based symbioses, phosphorus availability, and accounting for a modern world more productive than the Paleozoic. Geobiology Boyce, C. K., Ibarra, D. E., Nelsen, M. P., D'Antonio, M. P. 2022


    Evolution of high-productivity angiosperms has been regarded as a driver of Mesozoic ecosystem restructuring. However, terrestrial productivity is limited by availability of rock-derived nutrients such as phosphorus for which permanent increases in weathering would violate mass balance requirements of the long-term carbon cycle. The potential reality of productivity increases sustained since the Mesozoic is supported here with documentation of a dramatic increase in the evolution of nitrogen-fixing or nitrogen-scavenging symbioses, including more than 100 lineages of ectomycorrhizal and lichen-forming fungi and plants with specialized microbial associations. Given this evidence of broadly increased nitrogen availability, we explore via carbon cycle modeling how enhanced phosphorus availability might be sustained without violating mass balance requirements. Volcanism is the dominant carbon input, dictating peaks in weathering outputs up to twice modern values. However, times of weathering rate suppression may be more important for setting system behavior, and the late Paleozoic was the only extended period over which rates are expected to have remained lower than modern. Modeling results are consistent with terrestrial organic matter deposition that accompanied Paleozoic vascular plant evolution having suppressed weathering fluxes by providing an alternative sink of atmospheric CO2 . Suppression would have then been progressively lifted as the crustal reservoir's holding capacity for terrestrial organic matter saturated back toward steady state with deposition of new organic matter balanced by erosion of older organic deposits. Although not an absolute increase, weathering fluxes returning to early Paleozoic conditions would represent a novel regime for the complex land biota that evolved in the interim. Volcanism-based peaks in Mesozoic weathering far surpass the modern rates that sustain a complex diversity of nitrogen-based symbioses; only in the late Paleozoic might these ecologies have been suppressed by significantly lower rates. Thus, angiosperms are posited to be another effect rather than proximal cause of Mesozoic upheaval.

    View details for DOI 10.1111/gbi.12519

    View details for PubMedID 35949039

  • What to Do with Prototaxites? INTERNATIONAL JOURNAL OF PLANT SCIENCES Nelsen, M. P., Boyce, C. 2022

    View details for DOI 10.1086/720688

    View details for Web of Science ID 000803651200001

  • Two new leptosporangiate ferns from in situ volcanic ash of the Whetstone Horizon (Kladno Formation, Pennsylvanian), Pilsen Basin, Czech Republic REVIEW OF PALAEOBOTANY AND PALYNOLOGY Psenicka, J., Zhou, W., Boyce, C., Frojdova, J., Bek, J., Oplustil, S., Wang, J. 2022; 299
  • Generating and testing hypotheses about the fossil record of insect herbivory with a theoretical ecospace REVIEW OF PALAEOBOTANY AND PALYNOLOGY Schachat, S. R., Payne, J. L., Boyce, C., Labandeira, C. C. 2022; 297
  • The impact of vegetation on meandering rivers Nature Reviews Earth & Environment Ielpi, A., Lapôtre, M., Gibling, M., Boyce, C. 2022
  • A new anachoropterid fern from the Asselian (Cisuralian) Wuda Tuff Flora REVIEW OF PALAEOBOTANY AND PALYNOLOGY Zhou, W., Psenicka, J., Bek, J., Wan, M., Boyce, C., Wang, J. 2021; 294
  • Primary tissues dominated ground-level trunk diameter in Sigillaria: evidence from the Wuda Tuff, Inner Mongolia JOURNAL OF THE GEOLOGICAL SOCIETY D'Antonio, M. P., Boyce, C., Zhou, W., Pfefferkorn, H. W., Wang, J. 2021
  • Lepidoptera demonstrate the relevance of Murray's Law to circulatory systems with tidal flow. BMC biology Schachat, S. R., Boyce, C. K., Payne, J. L., Lentink, D. 2021; 19 (1): 204


    BACKGROUND: Murray's Law, which describes the branching architecture of bifurcating tubes, predicts the morphology of vessels in many amniotes and plants. Here, we use insects to explore the universality of Murray's Law and to evaluate its predictive power for the wing venation of Lepidoptera, one of the most diverse insect orders. Lepidoptera are particularly relevant to the universality of Murray's Law because their wing veins have tidal, or oscillatory, flow of air and hemolymph. We examined over one thousand wings representing 667 species of Lepidoptera.RESULTS: We found that veins with a diameter above approximately 50 microns conform to Murray's Law, with veins below 50 microns in diameter becoming less and less likely to conform to Murray's Law as they narrow. The minute veins that are most likely to deviate from Murray's Law are also the most likely to have atrophied, which prevents efficient fluid transport regardless of branching architecture. However, the veins of many taxa continue to branch distally to the areas where they atrophied, and these too conform to Murray's Law at larger diameters (e.g., Sesiidae).CONCLUSIONS: This finding suggests that conformity to Murray's Law in larger taxa may reflect requirements for structural support as much as fluid transport, or may indicate that selective pressures for fluid transport are stronger during the pupal stage-during wing development prior to vein atrophy-than the adult stage. Our results increase the taxonomic scope of Murray's Law and provide greater clarity about the relevance of body size.

    View details for DOI 10.1186/s12915-021-01130-0

    View details for PubMedID 34526028

  • An upright psaroniaceous stump and two surrounding pecopteroids from the early Permian Wuda Tuff Flora PALAEOWORLD Zhou, W., D'Antonio, M. P., Boyce, C., Wang, J. 2021; 30 (3): 451-460
  • Secondary phloem in arborescent lycopsids. The New phytologist D'Antonio, M. P., Boyce, C. K. 2021


    Consensus regarding arborescent lycopsid gross anatomy has not been reached in 150 years of study (Williamson, 1872; Walton, 1935; Pannell, 1942; Felix, 1952; Andrews & Murdy, 1958; Eggert, 1961; Bateman, 1994; Krings et al., 2011; Boyce & DiMichele, 2016; Hetherington et al., 2016; D'Antonio & Boyce, 2020; D'Antonio et al., 2020; DiMichele & Bateman, 2020). By comparison, the idea that they did not produce secondary phloem originated in the mid-19th century (Williamson, 1872).

    View details for DOI 10.1111/nph.17641

    View details for PubMedID 34309033

  • Maximum CO2 diffusion inside leaves is limited by the scaling of cell size and genome size. Proceedings. Biological sciences Théroux-Rancourt, G. n., Roddy, A. B., Earles, J. M., Gilbert, M. E., Zwieniecki, M. A., Boyce, C. K., Tholen, D. n., McElrone, A. J., Simonin, K. A., Brodersen, C. R. 2021; 288 (1945): 20203145


    Maintaining high rates of photosynthesis in leaves requires efficient movement of CO2 from the atmosphere to the mesophyll cells inside the leaf where CO2 is converted into sugar. CO2 diffusion inside the leaf depends directly on the structure of the mesophyll cells and their surrounding airspace, which have been difficult to characterize because of their inherently three-dimensional organization. Yet faster CO2 diffusion inside the leaf was probably critical in elevating rates of photosynthesis that occurred among angiosperm lineages. Here we characterize the three-dimensional surface area of the leaf mesophyll across vascular plants. We show that genome size determines the sizes and packing densities of cells in all leaf tissues and that smaller cells enable more mesophyll surface area to be packed into the leaf volume, facilitating higher CO2 diffusion. Measurements and modelling revealed that the spongy mesophyll layer better facilitates gaseous phase diffusion while the palisade mesophyll layer better facilitates liquid-phase diffusion. Our results demonstrate that genome downsizing among the angiosperms was critical to restructuring the entire pathway of CO2 diffusion into and through the leaf, maintaining high rates of CO2 supply to the leaf mesophyll despite declining atmospheric CO2 levels during the Cretaceous.

    View details for DOI 10.1098/rspb.2020.3145

    View details for PubMedID 33622134

  • Two new species of Sigillaria Brongniart from the Wuda Tuff (Asselian: Inner Mongolia, China) and their implications for lepidodendrid life history reconstruction Review of Palaeobotany and Palynology D'Antonio, M. P., Boyce, C. K., Wang, J. 2021; 294
  • The macroevolutionary dynamics of symbiotic and phenotypic diversification in lichens. Proceedings of the National Academy of Sciences of the United States of America Nelsen, M. P., Lucking, R., Boyce, C. K., Lumbsch, H. T., Ree, R. H. 2020


    Symbioses are evolutionarily pervasive and play fundamental roles in structuring ecosystems, yet our understanding of their macroevolutionary origins, persistence, and consequences is incomplete. We traced the macroevolutionary history of symbiotic and phenotypic diversification in an iconic symbiosis, lichens. By inferring the most comprehensive time-scaled phylogeny of lichen-forming fungi (LFF) to date (over 3,300 species), we identified shifts among symbiont classes that broadly coincided with the convergent evolution of phylogenetically or functionally similar associations in diverse lineages (plants, fungi, bacteria). While a relatively recent loss of lichenization in Lecanoromycetes was previously identified, our work instead suggests lichenization was abandoned far earlier, interrupting what had previously been considered a direct switch between trebouxiophycean and trentepohlialean algal symbionts. Consequently, some of the most diverse clades of LFF are instead derived from nonlichenized ancestors and re-evolved lichenization with Trentepohliales algae, a clade that also facilitated lichenization in unrelated lineages of LFF. Furthermore, while symbiont identity and symbiotic phenotype influence the ecology and physiology of lichens, they are not correlated with rates of lineage birth and death, suggesting more complex dynamics underly lichen diversification. Finally, diversification patterns of LFF differed from those of wood-rotting and ectomycorrhizal taxa, likely reflecting contrasts in their fundamental biological properties. Together, our work provides a timeline for the ecological contributions of lichens, and reshapes our understanding of symbiotic persistence in a classic model of symbiosis.

    View details for DOI 10.1073/pnas.2001913117

    View details for PubMedID 32796103

  • Land plant evolution decreased, rather than increased, weathering rates GEOLOGY D'Antonio, M. P., Ibarra, D. E., Boyce, C. 2020; 48 (1): 29–33

    View details for DOI 10.1130/G46776.1

    View details for Web of Science ID 000505235200008

  • Arborescent lycopsid periderm production was limited. The New phytologist D'Antonio, M. P., Boyce, C. K. 2020


    Late Paleozoic arborescent lycopsids have been thought to have grown from sporelings into large trees through the production of a periderm cylinder, particularly massive in the proximal portion of the trunk and tapering distally, with this rind of bark providing most of their structural support. Here, we argue that physiological limitations would have prohibited the production of thick periderm and test this hypothesis using multiple independent lines of evidence derived from anatomical permineralization and surface impression fossils that allow both direct and indirect measurement of periderm radial thickness. Across all six genera of Pennsylvanian arborescent lycopsids that were investigated, all evidence indicates limited periderm production: typically less than 5 cm, always less than 15 cm, even in trunks that would have reached a meter or more in diameter. The large amount of arborescent lycopsid periderm in Middle Pennsylvanian coals represents taphonomic enrichment rather than a true anatomical signal, complicating interpretation of their biology including biomechanics and early ontogeny.

    View details for DOI 10.1111/nph.16727

    View details for PubMedID 32506426

  • The prospects for constraining productivity through time with the whole-plant physiology of fossils NEW PHYTOLOGIST Boyce, C., Zwieniecki, M. A. 2019; 223 (1): 40–49

    View details for DOI 10.1111/nph.15446

    View details for Web of Science ID 000470759100007

  • Modeling the consequences of land plant evolution on silicate weathering American Journal of Science Ibarra, D. E., Caves Rugenstein, J. K., Bachan, A., Baresch, A., Lau, K. V., Thomas, D. L., Lee, J., Boyce, C., Chamberlain, C. 2019; 319 (1): 1-43

    View details for DOI 10.2475/01.2019.01

  • A left-handed fern twiner in a Permian swamp forest. Current biology : CB Zhou, W. n., Li, D. n., Pšenička, J. n., Boyce, C. K., Wang, J. n. 2019; 29 (22): R1172–R1173


    The twining habit is a climbing strategy that helps slender plants grow upward by using circumnutation around other plants. In geological history, climbing may have already been present in the first Middle Devonian forests, as indicated by possible climbers among aneurophytalean progymnosperms [1] and lycopsids [2]. By the late Carboniferous, climbing was both more common and diverse - preserved in swamp forests with modes of attachment ranging from aerial roots to appendages modified into hooks and tendrils on the leaves [3]. However, all of these diagnoses of a climbing habit are based upon either indirect morphological characteristics of the purported climber or on direct physical contact with a host plant, but without direct preservation of twining [3,4]. Permineralized epiphytes have been preserved in the Carboniferous [5], but the interpretation of scars purported to have been caused by twiners that have been found on trunk compressions of potential host-plants has been questioned [5] (see Supplemental Information). Direct preservation of a climber engaged in true twining around a host has only been documented in the Miocene Shanwang Formation of Eastern China, albeit with the identity of the twiner difficult to establish and likely to be a self-twiner [6]. Here, we report a climbing fern engaged in left-handed twining around a seed plant from the early Permian Wuda Tuff fossil Lagerstätte of Inner Mongolia, China [7]. Moreover, the host plant is likely to also be a climber based on its overall form. Such a climber-climbing-a-climber phenomenon signals the potential ecological complexity of late Paleozoic forests.

    View details for DOI 10.1016/j.cub.2019.10.005

    View details for PubMedID 31743669

  • No support for the emergence of lichens prior to the evolution of vascular plants. Geobiology Nelsen, M. P., Lücking, R. n., Boyce, C. K., Lumbsch, H. T., Ree, R. H. 2019


    The early-successional status of lichens in modern terrestrial ecosystems, together with the role lichen-mediated weathering plays in the carbon cycle, have contributed to the long and widely held assumption that lichens occupied early terrestrial ecosystems prior to the evolution of vascular plants and drove global change during this time. Their poor preservation potential and the classification of ambiguous fossils as lichens or other fungal-algal associations have further reinforced this view. As unambiguous fossil data are lacking to demonstrate the presence of lichens prior to vascular plants, we utilize an alternate approach to assess their historic presence in early terrestrial ecosystems. Here, we analyze new time-calibrated phylogenies of ascomycete fungi and chlorophytan algae, that intensively sample lineages with lichen symbionts. Age estimates for several interacting clades show broad congruence and demonstrate that fungal origins of lichenization postdate the earliest tracheophytes. Coupled with the absence of unambiguous fossil data, our work finds no support for lichens having mediated global change during the Neoproterozoic-early Paleozoic prior to vascular plants. We conclude by discussing our findings in the context of Neoproterozoic-Paleozoic terrestrial ecosystem evolution and the paleoecological context in which vascular plants evolved.

    View details for DOI 10.1111/gbi.12369

    View details for PubMedID 31729136

  • Competition for epidermal space in the evolution of leaves with high physiological rates NEW PHYTOLOGIST Baresch, A., Crifo, C., Boyce, C. 2019; 221 (2): 628–39

    View details for DOI 10.1111/nph.15476

    View details for Web of Science ID 000453883200007

  • Fast or slow for the arborescent lycopsids? Response to Thomas & Cleal (2018) 'Arborescent lycophyte growth in the late Carboniferous coal swamps' NEW PHYTOLOGIST Boyce, C., DiMichele, W. A. 2018; 218 (3): 891–93

    View details for DOI 10.1111/nph.15059

    View details for Web of Science ID 000430127000004

    View details for PubMedID 29457227

  • Phanerozoic pO2 and the early evolution of terrestrial animals Proceedings of the Royal Society B: Biological Sciences Schachat, S. R., Labandiera, C. C., Saltzman, M. R., Cramer, B. D., Payne, J. L., Boyce, C. K. 2018; 285

    View details for DOI 10.1098/rspb.2017.2631

  • The bias of a two-dimensional view: comparing two-dimensional and three-dimensional mesophyll surface area estimates using noninvasive imaging NEW PHYTOLOGIST Theroux-Rancourt, G., Earles, J., Gilbert, M. E., Zwieniecki, M. A., Boyce, C., McElrone, A. J., Brodersen, C. R. 2017; 215 (4): 1609–22


    The mesophyll surface area exposed to intercellular air space per leaf area (Sm ) is closely associated with CO2 diffusion and photosynthetic rates. Sm is typically estimated from two-dimensional (2D) leaf sections and corrected for the three-dimensional (3D) geometry of mesophyll cells, leading to potential differences between the estimated and actual cell surface area. Here, we examined how 2D methods used for estimating Sm compare with 3D values obtained from high-resolution X-ray microcomputed tomography (microCT) for 23 plant species, with broad phylogenetic and anatomical coverage. Relative to 3D, uncorrected 2D Sm estimates were, on average, 15-30% lower. Two of the four 2D Sm methods typically fell within 10% of 3D values. For most species, only a few 2D slices were needed to accurately estimate Sm within 10% of the whole leaf sample median. However, leaves with reticulate vein networks required more sections because of a more heterogeneous vein coverage across slices. These results provide the first comparison of the accuracy of 2D methods in estimating the complex 3D geometry of internal leaf surfaces. Because microCT is not readily available, we provide guidance for using standard light microscopy techniques, as well as recommending standardization of reporting Sm values.

    View details for PubMedID 28691233

  • Did trees grow up to the light, up to the wind, or down to the water? How modern high productivity colors perception of early plant evolution. New phytologist Boyce, C. K., Fan, Y., Zwieniecki, M. A. 2017


    Contents I. II. III. IV. V. Acknowledgements References SUMMARY: Flowering plants can be far more productive than other living land plants. Evidence is reviewed that productivity would have been uniformly lower and less CO2 -responsive before angiosperm evolution, particularly during the early evolution of vascular plants and forests in the Devonian and Carboniferous. This introduces important challenges because paleoecological interpretations have been rooted in understanding of modern angiosperm-dominated ecosystems. One key example is tree evolution: although often thought to reflect competition for light, light limitation is unlikely for plants with such low photosynthetic potential. Instead, during this early evolution, the capacities of trees for enhanced propagule dispersal, greater leaf area, and deep-rooting access to nutrients and the water table are all deemed more fundamental potential drivers than light.

    View details for DOI 10.1111/nph.14387

    View details for PubMedID 28054354

  • Plant Evolution and Climate Over Geological Timescales ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES, VOL 45 Boyce, C., Lee, J., Jeanloz, R., Freeman, K. H. 2017; 45: 61–87
  • Stomatal design principles in synthetic and real leaves. Journal of the Royal Society, Interface Zwieniecki, M. A., Haaning, K. S., Boyce, C. K., Jensen, K. H. 2016; 13 (124)


    Stomata are portals in plant leaves that control gas exchange for photosynthesis, a process fundamental to life on Earth. Gas fluxes and plant productivity depend on external factors such as light, water and CO2 availability and on the geometrical properties of the stoma pores. The link between stoma geometry and environmental factors has informed a wide range of scientific fields-from agriculture to climate science, where observed variations in stoma size and density are used to infer prehistoric atmospheric CO2 content. However, the physical mechanisms and design principles responsible for major trends in stomatal patterning are not well understood. Here, we use a combination of biomimetic experiments and theory to rationalize the observed changes in stoma geometry. We show that the observed correlations between stoma size and density are consistent with the hypothesis that plants favour efficient use of space and maximum control of dynamic gas conductivity, and that the capacity for gas exchange in plants has remained constant over at least the last 325 Myr. Our analysis provides a new measure to gauge the relative performance of species based on their stomatal characteristics.

    View details for PubMedID 27807270

  • Stomatal design principles in synthetic and real leaves JOURNAL OF THE ROYAL SOCIETY INTERFACE Zwieniecki, M. A., Haaning, K. S., Boyce, C., Jensen, K. H. 2016; 13 (124)
  • Delayed fungal evolution did not cause the Paleozoic peak in coal production PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Nelsen, M. P., DiMichele, W. A., Peters, S. E., Boyce, C. K. 2016; 113 (9): 2442-2447


    Organic carbon burial plays a critical role in Earth systems, influencing atmospheric O2 and CO2 concentrations and, thereby, climate. The Carboniferous Period of the Paleozoic is so named for massive, widespread coal deposits. A widely accepted explanation for this peak in coal production is a temporal lag between the evolution of abundant lignin production in woody plants and the subsequent evolution of lignin-degrading Agaricomycetes fungi, resulting in a period when vast amounts of lignin-rich plant material accumulated. Here, we reject this evolutionary lag hypothesis, based on assessment of phylogenomic, geochemical, paleontological, and stratigraphic evidence. Lignin-degrading Agaricomycetes may have been present before the Carboniferous, and lignin degradation was likely never restricted to them and their class II peroxidases, because lignin modification is known to occur via other enzymatic mechanisms in other fungal and bacterial lineages. Furthermore, a large proportion of Carboniferous coal horizons are dominated by unlignified lycopsid periderm with equivalent coal accumulation rates continuing through several transitions between floral dominance by lignin-poor lycopsids and lignin-rich tree ferns and seed plants. Thus, biochemical composition had little relevance to coal accumulation. Throughout the fossil record, evidence of decay is pervasive in all organic matter exposed subaerially during deposition, and high coal accumulation rates have continued to the present wherever environmental conditions permit. Rather than a consequence of a temporal decoupling of evolutionary innovations between fungi and plants, Paleozoic coal abundance was likely the result of a unique combination of everwet tropical conditions and extensive depositional systems during the assembly of Pangea.

    View details for DOI 10.1073/pnas.1517943113

    View details for Web of Science ID 000371204500050

    View details for PubMedID 26787881

    View details for PubMedCentralID PMC4780611

  • Arborescent lycopsid productivity and lifespan: Constraining the possibilities REVIEW OF PALAEOBOTANY AND PALYNOLOGY Boyce, C. K., DiMichele, W. A. 2016; 227: 97–110

    View details for DOI 10.1086/678089

    View details for Web of Science ID 000345987200007

  • Evolution of a unique anatomical precision in angiosperm leaf venation lifts constraints on vascular plant ecology. Proceedings. Biological sciences / The Royal Society Zwieniecki, M. A., Boyce, C. K. 2014; 281 (1779): 20132829-?


    The main role of leaf venation is to supply water across the photosynthetic surface to keep stomata open and allow access to atmospheric CO2 despite evaporative demand. The optimal uniform delivery of water occurs when the distance between veins equals the depth of vein placement within the leaf away from the evaporative surface. As presented here, only angiosperms maintain this anatomical optimum across all leaf thicknesses and different habitats, including sheltered environments where this optimization need not be required. Intriguingly, basal angiosperm lineages tend to be underinvested hydraulically; uniformly high optimization is derived independently in the magnoliids, monocots and core eudicots. Gymnosperms and ferns, including available fossils, are limited by their inability to produce high vein densities. The common association of ferns with shaded humid environments may, in part, be a direct evolutionary consequence of their inability to produce hydraulically optimized leaves. Some gymnosperms do approach optimal vein placement, but only by virtue of their ability to produce thick leaves most appropriate in environments requiring water conservation. Thus, this simple anatomical metric presents an important perspective on the evolution and phylogenetic distribution of plant ecologies and further evidence that the vegetative biology of flowering plants-not just their reproductive biology-is unique.

    View details for DOI 10.1098/rspb.2013.2829

    View details for PubMedID 24478301

  • Forest productivity and water stress in Amazonia: observations from GOSAT chlorophyll fluorescence PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES Lee, J., Frankenberg, C., van der Tol, C., Berry, J. A., Guanter, L., Boyce, C. K., Fisher, J. B., Morrow, E., Worden, J. R., Asefi, S., Badgley, G., Saatchi, S. 2013; 280 (1761)


    It is unclear to what extent seasonal water stress impacts on plant productivity over Amazonia. Using new Greenhouse gases Observing SATellite (GOSAT) satellite measurements of sun-induced chlorophyll fluorescence, we show that midday fluorescence varies with water availability, both of which decrease in the dry season over Amazonian regions with substantial dry season length, suggesting a parallel decrease in gross primary production (GPP). Using additional SeaWinds Scatterometer onboard QuikSCAT satellite measurements of canopy water content, we found a concomitant decrease in daily storage of canopy water content within branches and leaves during the dry season, supporting our conclusion. A large part (r(2) = 0.75) of the variance in observed monthly midday fluorescence from GOSAT is explained by water stress over moderately stressed evergreen forests over Amazonia, which is reproduced by model simulations that include a full physiological representation of photosynthesis and fluorescence. The strong relationship between GOSAT and model fluorescence (r(2) = 0.79) was obtained using a fixed leaf area index, indicating that GPP changes are more related to environmental conditions than chlorophyll contents. When the dry season extended to drought in 2010 over Amazonia, midday basin-wide GPP was reduced by 15 per cent compared with 2009.

    View details for DOI 10.1098/rspb.2013.0171

    View details for Web of Science ID 000318760500001

    View details for PubMedID 23760636

    View details for PubMedCentralID PMC3652436

  • Reduction of tropical land region precipitation variability via transpiration GEOPHYSICAL RESEARCH LETTERS Lee, J., Lintner, B. R., Neelin, J. D., Jiang, X., Gentine, P., Boyce, C. K., Fisher, J. B., Perron, J. T., Kubar, T. L., Lee, J., Worden, J. 2012; 39

    View details for DOI 10.1086/665818

    View details for Web of Science ID 000305977100007


    View details for DOI 10.1086/665820

    View details for Web of Science ID 000305977100002

  • Leaf fossil record suggests limited influence of atmospheric CO2 on terrestrial productivity prior to angiosperm evolution PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Boyce, C. K., Zwieniecki, M. A. 2012; 109 (26): 10403-10408


    Declining CO(2) over the Cretaceous has been suggested as an evolutionary driver of the high leaf vein densities (7-28 mm mm(-2)) that are unique to the angiosperms throughout all of Earth history. Photosynthetic modeling indicated the link between high vein density and productivity documented in the modern low-CO(2) regime would be lost as CO(2) concentrations increased but also implied that plants with very low vein densities (less than 3 mm mm(-2)) should experience substantial disadvantages with high CO(2). Thus, the hypothesized relationship between CO(2) and plant evolution can be tested through analysis of the concurrent histories of alternative lineages, because an extrinsic driver like atmospheric CO(2) should affect all plants and not just the flowering plants. No such relationship is seen. Regardless of CO(2) concentrations, low vein densities are equally common among nonangiosperms throughout history and common enough to include forest canopies and not just obligate shade species that will always be of limited productivity. Modeling results can be reconciled with the fossil record if maximum assimilation rates of nonflowering plants are capped well below those of flowering plants, capturing biochemical and physiological differences that would be consistent with extant plants but previously unrecognized in the fossil record. Although previous photosynthetic modeling suggested that productivity would double or triple with each Phanerozoic transition from low to high CO(2), productivity changes are likely to have been limited before a substantial increase accompanying the evolution of flowering plants.

    View details for DOI 10.1073/pnas.1203769109

    View details for Web of Science ID 000306291400065

    View details for PubMedID 22689947

    View details for PubMedCentralID PMC3387114

  • Land use change exacerbates tropical South American drought by sea surface temperature variability GEOPHYSICAL RESEARCH LETTERS Lee, J., Lintner, B. R., Boyce, C. K., Lawrence, P. J. 2011; 38
  • Could land plant evolution have fed the marine revolution? PALEONTOLOGICAL RESEARCH Boyce, C. K., Lee, J. 2011; 15 (2): 100-105
  • The evolution and functional significance of leaf shape in the angiosperms FUNCTIONAL PLANT BIOLOGY Nicotra, A. B., Leigh, A., Boyce, C. K., Jones, C. S., Niklas, K. J., Royer, D. L., Tsukaya, H. 2011; 38 (7): 535-552

    View details for DOI 10.1071/FP11057

    View details for Web of Science ID 000292603900001

  • Structural and hydraulic correlates of heterophylly in Ginkgo biloba NEW PHYTOLOGIST Leigh, A., Zwieniecki, M. A., Rockwell, F. E., Boyce, C. K., Nicotra, A. B., Holbrook, N. M. 2011; 189 (2): 459-470


    This study investigates the functional significance of heterophylly in Ginkgo biloba, where leaves borne on short shoots are ontogenetically distinct from those on long shoots. Short shoots are compact, with minimal internodal elongation; their leaves are supplied with water through mature branches. Long shoots extend the canopy and have significant internodal elongation; their expanding leaves receive water from a shoot that is itself maturing. Morphology, stomatal traits, hydraulic architecture, Huber values, water transport efficiency, in situ gas exchange and laboratory-based steady-state hydraulic conductance were examined for each leaf type. Both structure and physiology differed markedly between the two leaf types. Short-shoot leaves were thinner and had higher vein density, lower stomatal pore index, smaller bundle sheath extensions and lower hydraulic conductance than long-shoot leaves. Long shoots had lower xylem area:leaf area ratios than short shoots during leaf expansion, but this ratio was reversed at shoot maturity. Long-shoot leaves had higher rates of photosynthesis, stomatal conductance and transpiration than short-shoot leaves. We propose that structural differences between the two G. biloba leaf types reflect greater hydraulic limitation of long-shoot leaves during expansion. In turn, differences in physiological performance of short- and long-shoot leaves correspond to their distinct ontogeny and architecture.

    View details for DOI 10.1111/j.1469-8137.2010.03476.x

    View details for Web of Science ID 000285761500013

    View details for PubMedID 20880226

  • Impact of the hydraulic capacity of plants on water and carbon fluxes in tropical South America JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES Lee, J., Boyce, K. 2010; 115
  • An exceptional role for flowering plant physiology in the expansion of tropical rainforests and biodiversity PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES Boyce, C. K., Lee, J. 2010; 277 (1699): 3437-3443


    Movement of water from soil to atmosphere by plant transpiration can feed precipitation, but is limited by the hydraulic capacities of plants, which have not been uniform through time. The flowering plants that dominate modern vegetation possess transpiration capacities that are dramatically higher than any other plants, living or extinct. Transpiration operates at the level of the leaf, however, and how the impact of this physiological revolution scales up to the landscape and larger environment remains unclear. Here, climate modelling demonstrates that angiosperms help ensure aseasonally high levels of precipitation in the modern tropics. Most strikingly, replacement of angiosperm with non-angiosperm vegetation would result in a hotter, drier and more seasonal Amazon basin, decreasing the overall area of ever-wet rainforest by 80 per cent. Thus, flowering plant ecological dominance has strongly altered climate and the global hydrological cycle. Because tropical biodiversity is closely tied to precipitation and rainforest area, angiosperm climate modification may have promoted diversification of the angiosperms themselves, as well as radiations of diverse vertebrate and invertebrate animal lineages and of epiphytic plants. Their exceptional potential for environmental modification may have contributed to divergent responses to similar climates and global perturbations, like mass extinctions, before and after angiosperm evolution.

    View details for DOI 10.1098/rspb.2010.0485

    View details for Web of Science ID 000283448800008

    View details for PubMedID 20554551

    View details for PubMedCentralID PMC2982219

  • X-ray photoelectron emission spectromicroscopic analysis of arborescent lycopsid cell wall composition and Carboniferous coal ball preservation INTERNATIONAL JOURNAL OF COAL GEOLOGY Boyce, C. K., Abrecht, M., Zhou, D., Gilbert, P. U. 2010; 83 (2-3): 146-153
  • Carbon sources for the Palaeozoic giant fungus Prototaxites inferred from modern analogues PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES Hobbie, E. A., Boyce, C. K. 2010; 277 (1691): 2149-2156


    A wide range of carbon isotope values in the Devonian fossil Prototaxites has been interpreted to support heterotrophy and the classification of Prototaxites as a giant fungus. This inference remains controversial because of the huge size of Prototaxites relative to co-occurring terrestrial vegetation and the lack of existing fungal analogues that display equally broad isotopic ranges. Here, we show wide isotopic variability in the modern saprotrophic fungus Arrhenia obscurata collected adjacent to shallow meltwater pools of a sparsely vegetated glacial succession in the Washington Cascades, USA. Soils collected specifically around the edges of these pools were up to 5 per thousand higher in delta(13)C than adjacent soils consistent with C(3) origin. Microbial sources of primary production appear to cause these high delta(13)C values, and the environment may be analogous to that of the Early Devonian landscapes, where Prototaxites individuals with extreme isotopic variance were found. Carbon isotopes are also compared in Prototaxites, Devonian terrestrial vascular plants, and Devonian algal-derived lake sediments. Prototaxites isotopic values show little correspondence with those of contemporaneous tracheophytes, providing further evidence that non-vascular land plants or aquatic microbes were important contributors to its carbon sources. Thus, a saprotrophic fungal identity is supported for Prototaxites, which may have relied on deposits of algal-derived organic matter in floodplain environments that were less dominated by vascular plants than a straight reading of the macrofossil record might suggest.

    View details for DOI 10.1098/rspb.2010.0201

    View details for Web of Science ID 000278569700007

    View details for PubMedID 20335209

    View details for PubMedCentralID PMC2880155


    View details for DOI 10.3732/ajb.1000104

    View details for Web of Science ID 000279548600001

    View details for PubMedID 21616858

  • The evolution of plant development in a paleontological context CURRENT OPINION IN PLANT BIOLOGY Boyce, C. K. 2010; 13 (1): 102-107


    Contrary to what might be expected from the observation of extant plants alone, the fossil record indicates that most aspects of vascular plant form evolved multiple times during their Paleozoic radiation. Opportunity is increasing to unite information from fossil and living plants to understand the evolution of developmental mechanisms and each field can provide tests for hypotheses derived from the other. The paleontological context to recent advances in developmental genetics is reviewed for the evolution of a functionally independent sporophyte generation, of leaves, and of roots-all of which are integral to understanding the explosive radiation of vascular plants during the Devonian, 400 million years ago.

    View details for DOI 10.1016/j.pbi.2009.10.001

    View details for Web of Science ID 000275095200016

    View details for PubMedID 19897405


    View details for DOI 10.3417/2009143

    View details for Web of Science ID 000285946400003

  • Angiosperm leaf vein evolution was physiologically and environmentally transformative PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES Boyce, C. K., Brodribb, T. J., Feild, T. S., Zwieniecki, M. A. 2009; 276 (1663): 1771-1776


    The veins that irrigate leaves during photosynthesis are demonstrated to be strikingly more abundant in flowering plants than in any other vascular plant lineage. Angiosperm vein densities average 8 mm of vein per mm(2) of leaf area and can reach 25 mm mm(-2), whereas such high densities are absent from all other plants, living or extinct. Leaves of non-angiosperms have consistently averaged close to 2 mm mm(-2) throughout 380 million years of evolution despite a complex history that has involved four or more independent origins of laminate leaves with many veins and dramatic changes in climate and atmospheric composition. We further demonstrate that the high leaf vein densities unique to the angiosperms enable unparalleled transpiration rates, extending previous work indicating a strong correlation between vein density and assimilation rates. Because vein density is directly measurable in fossils, these correlations provide new access to the physiology of extinct plants and how they may have impacted their environments. First, the high assimilation rates currently confined to the angiosperms among living plants are likely to have been unique throughout evolutionary history. Second, the transpiration-driven recycling of water that is important for bolstering precipitation in modern tropical rainforests might have been significantly less in a world before the angiosperms.

    View details for DOI 10.1098/rspb.2008.1919

    View details for Web of Science ID 000264936500005

    View details for PubMedID 19324775

    View details for PubMedCentralID PMC2674498

  • Seeing the forest with the leaves - clues to canopy placement from leaf fossil size and venation characteristics GEOBIOLOGY Boyce, C. K. 2009; 7 (2): 192-199


    Although a variety of leaf characteristics appear to be induced by light environment during development, analysis of ontogenetic changes in living broad leaved trees has suggested that a number of other traits also lumped into the classic 'sun' versus 'shade' morphological distinctions, including leaf size, shape, and vein density, are instead controlled largely by local hydraulic environment within the tree canopy. The regularity in how these traits vary with canopy placement suggests a method for addressing a classic paleobotanical quandary: the stature of the source plant - from herb or shrub to canopy tree - is typically unknown for leaf fossils. The study of Ginkgo here complements previous work on Quercus that indicated that leaves throughout the crown are identical in size and venation at the time of bud break and that morphological adaptation to the local microenvironment takes place largely during the expansion phase after the determination of the vascular architecture is complete. Hence, variation in vein density does not reflect differential vein production so much as the distortion of similar vein networks over different final surface areas driven by variation in local hydraulic supply during expansion. Unlike the diffusely growing leaves of the angiosperm, Quercus, the marginally growing leaves of Ginkgo do show some potential for differential vein production, but expansion effects still dominate. The approach suggested here may prove useful for assessing the likelihood that two distinct fossil morphospecies actually represent leaves of the same plant and to gather information concerning canopy structure from disarticulated leaves.

    View details for DOI 10.1111/j.1472-4669.2008.00176.x

    View details for Web of Science ID 000264635800007

    View details for PubMedID 19207570

  • How green was Cooksonia? The importance of size in understanding the early evolution of physiology in the vascular plant lineage PALEOBIOLOGY Boyce, C. K. 2008; 34 (2): 179-194
  • The fossil record of plant physiology and development—What leaves can tell us Paleontological Society Papers Boyce, C. K. 2008; 14: 133-146
  • Mechanisms of laminar growth in morphologically convergent leaves and flower petals INTERNATIONAL JOURNAL OF PLANT SCIENCES Boyce, C. K. 2007; 168 (8): 1151-1156

    View details for DOI 10.1086/520730

    View details for Web of Science ID 000249331500004

  • Devonian landscape heterogeneity recorded by a giant fungus GEOLOGY Boyce, C. K., Hotton, C. L., Fogel, M. L., Cody, G. D., Hazen, R. M., Knoll, A. H., Hueber, F. M. 2007; 35 (5): 399-402

    View details for DOI 10.1130/G23384A.1

    View details for Web of Science ID 000250253900004

  • Hydraulic design of pine needles: one-dimensional optimization for single-vein leaves PLANT CELL AND ENVIRONMENT Zwieniecki, M. A., Stone, H. A., Leigh, A., Boyce, C. K., Holbrook, N. M. 2006; 29 (5): 803-809


    Single-vein leaves have the simplest hydraulic design possible, yet even this linear water delivery system can be modulated to improve physiological performance. We determined the optimal distribution of transport capacity that minimizes pressure drop per given investment in xylem permeability along the needle for a given length without a change in total water delivery, or maximizes needle length for a given pressure difference between petiole and needle tip. This theory was tested by comparative analysis of the hydraulic design of three pine species that differ in the length of their needles [Pinus palustris (Engl.) Miller, approximately 50 cm; Pinus ponderosa Lawson & Lawson, approximately 20 cm and Pinus rigida Miller, approximately 5 cm]. In all three species, the distribution of hydraulic permeability was similar to that predicted by the optimum solution. The needles of P. palustris showed an almost perfect match between predicted and actual hydraulic optimum solution, providing evidence that vein design is a significant factor in the hydraulic design of pine leaves.

    View details for DOI 10.1111/j.1365-3040.2005.01448.x

    View details for Web of Science ID 000237133100007

    View details for PubMedID 17087464

  • Patterns of segregation and convergence in the evolution of fern and seed plant leaf morphologies PALEOBIOLOGY Boyce, C. K. 2005; 31 (1): 117-140
  • The evolutionary history of roots and leaves Vascular transport in plants Boyce, C. K. edited by Holbrook, N. M., Zweiniecki, M. A. Elsevier Sciences/Academic Press. 2005: 479–499
  • Evolution of xylem lignification and hydrogel transport regulation PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Boyce, C. K., Zwieniecki, M. A., Cody, G. D., Jacobsen, C., Wirick, S., Knoll, A. H., Holbrook, N. M. 2004; 101 (50): 17555-17558


    In vascular plants, the polysaccharide-based walls of water-conducting cells are strengthened by impregnation with the polyphenolic polymer lignin. The fine-scale patterning of lignin deposition in water-conducting cells is shown here to vary phylogenetically across vascular plants. The extent to which water transport in xylem cells can be modified in response to changes in the ionic content of xylem sap also is shown to vary in correlation with variation in lignification patterns, consistent with the proposed mechanism for hydraulic response through size change of middle-lamella pectins. This covariation suggests that the fine-scale distribution of hydrophilic polysaccharides and hydrophobic lignin can affect hydraulic as well as mechanical properties, and that the evolutionary diversification of vascular cells thus reflects biochemical as well as morphological innovations evolved to fulfill opposing cell functions of transport and structural support.

    View details for DOI 10.1073/pnas.0408024101

    View details for Web of Science ID 000225803400045

    View details for PubMedID 15574502

    View details for PubMedCentralID PMC536047

  • Functional design space of single-veined leaves: Role of tissue hydraulic properties in constraining leaf size and shape ANNALS OF BOTANY Zwieniecki, M. A., Boyce, C. K., Holbrook, N. M. 2004; 94 (4): 507-513


    Morphological diversity of leaves is usually quantified with geometrical characters, while in many cases a simple set of biophysical parameters are involved in constraining size and shape. One of the main physiological functions of the leaf is transpiration and thus one can expect that leaf hydraulic parameters can be used to predict potential morphologies, although with the caveat that morphology in turn influences physiological parameters including light interception and boundary layer thickness and thereby heat transfer and net photosynthesis.An iterative model was used to determine the relative sizes and shapes that are functionally possible for single-veined leaves as defined by their ability to supply the entire leaf lamina with sufficient water to prevent stomatal closure. The model variables include the hydraulic resistances associated with vein axial and radial transport, as well as with water movement through the mesophyll and the leaf surface.The four parameters included in the model are sufficient to define a hydraulic functional design space that includes all single-veined leaf shapes found in nature, including scale-, awl- and needle-like morphologies. This exercise demonstrates that hydraulic parameters have dissimilar effects: surface resistance primarily affects leaf size, while radial and mesophyll resistances primarily affect leaf shape.These distinctions between hydraulic parameters, as well as the differential accessibility of different morphologies, might relate to the convergent evolutionary patterns seen in a variety of fossil lineages concerning overall morphology and anatomical detail that frequently have evolved in linear and simple multi-veined leaves.

    View details for DOI 10.1093/aob/mch173

    View details for Web of Science ID 000224341100003

    View details for PubMedID 15319225

  • Hydraulic limitations imposed by crown placement determine final size and shape of Quercus rubra L. leaves PLANT CELL AND ENVIRONMENT Zwieniecki, M. A., Boyce, C. K., Holbrook, N. M. 2004; 27 (3): 357-365
  • Chemical evidence for cell wall lignification and the evolution of tracheids in early Devonian plants INTERNATIONAL JOURNAL OF PLANT SCIENCES Boyce, C. K., Cody, G. D., Fogel, M. L., Hazen, R. M., Alexander, C. M., Knoll, A. H. 2003; 164 (5): 691-702
  • Hydraulic architecture of leaf venation in Laurus nobilis L. PLANT CELL AND ENVIRONMENT Zwieniecki, M. A., Melcher, P. J., Boyce, C. K., Sack, L., Holbrook, N. M. 2002; 25 (11): 1445-1450
  • Preservation of cell wall chemistry and microstructure in plant fossils as old as 400 million years: detection by carbon X-ray absorption spectromicroscopy Geology Boyce, C. K., Cody, G. D., Feser, M., Jacobsen, C., Knoll, A. H., Wirick, S. 2002; 30: 1039-1042`
  • Evolution of developmental potential and the multiple independent origins of leaves in Paleozoic vascular plants PALEOBIOLOGY Boyce, C. K., Knoll, A. H. 2002; 28 (1): 70-100
  • Nondestructive, in situ, cellular-scale mapping of elemental abundances including organic carbon in permineralized fossils PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Boyce, C. K., Hazen, R. M., Knoll, A. H. 2001; 98 (11): 5970-5974


    The electron microprobe allows elemental abundances to be mapped at the microm scale, but until now high resolution mapping of light elements has been challenging. Modifications of electron microprobe procedure permit fine-scale mapping of carbon. When applied to permineralized fossils, this technique allows simultaneous mapping of organic material, major matrix-forming elements, and trace elements with microm-scale resolution. The resulting data make it possible to test taphonomic hypotheses for the formation of anatomically preserved silicified fossils, including the role of trace elements in the initiation of silica precipitation and in the prevention of organic degradation. The technique allows one to understand the localization of preserved organic matter before undertaking destructive chemical analyses and, because it is nondestructive, offers a potentially important tool for astrobiological investigations of samples returned from Mars or other solar system bodies.

    View details for Web of Science ID 000168883700009

    View details for PubMedID 11371632

    View details for PubMedCentralID PMC33407

  • Measurement of the threshold sensitivity of honeybees to weak, extremely low-frequency magnetic fields JOURNAL OF EXPERIMENTAL BIOLOGY Kirschvink, J. L., Padmanabha, S., Boyce, C. K., Oglesby, J. 1997; 200 (9): 1363-1368


    Experiments reported previously demonstrate that free-flying honeybees are able to detect static intensity fluctuations as weak as 26 nT against the background, earth-strength magnetic field. We report here an extension of this work to weak, alternating fields at frequencies of 10 and 60 Hz. Our results indicate that the sensitivity of the honeybee magnetoreception system decreases rapidly with increasing frequency. At 60 Hz, alternating field strengths above 100 µT are required to elicit discrimination. These results are consistent with biophysical predictions of a magnetite-based magnetoreceptor.

    View details for Web of Science ID A1997WZ38300009