1
|
Nguyen AT, Atkinson BA. Cretaceous and Paleocene fossils reveal an extinct higher clade within Cornales, the dogwood order. AMERICAN JOURNAL OF BOTANY 2024; 111:e16372. [PMID: 39010697 DOI: 10.1002/ajb2.16372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/29/2024] [Accepted: 05/01/2024] [Indexed: 07/17/2024]
Abstract
PREMISE Characterization and phylogenetic integration of fossil angiosperms with uncertain affinities is relatively limited, which may obscure the diversity of extinct higher taxa in the flowering plant tree of life. The order Cornales contains a diversity of extinct taxa with uncertain familial affinities that make it an ideal group for studying turnover in angiosperms. Here, we describe a new extinct genus of Cornales unassignable to an extant family and conduct a series of phylogenetic analyses to reconstruct relationships of fossils across the order. METHODS Two permineralized endocarps were collected from the Cedar District Formation (Campanian, 82-80 Ma) of Sucia Island, State of Washington, United States. Fossils were sectioned with the cellulose acetate peel technique and incorporated into a morphological dataset. To assess the utility of this dataset to accurately place taxa in their respective clades, we used a series of phylogenetic pseudofossilization analyses. We then conducted a total-evidence analysis and a scaffold-based approach to determine relationships of fossils. RESULTS Based on their unique combination of characters, the fossils represent a new genus, Fenestracarpa washingtonensis gen. nov. et sp. nov. Pseudofossilization analyses indicate that our morphological dataset can be used to accurately recover taxa at the major clade to family level, generally with moderate to high support. The total-evidence and scaffold-based analyses recovered Fenestracarpa and other fossil genera in an entirely extinct clade within Cornales. CONCLUSIONS Our findings increase the reported diversity of extinct Cornales and indicate that the order's initial radiation likely included the divergence of an extinct higher clade that endured the end-Cretaceous Mass extinction but perished during the Cenozoic.
Collapse
Affiliation(s)
- Austin T Nguyen
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, 66045, KS, USA
- Biodiversity Institute, University of Kansas, Lawrence, 66045, KS, USA
| | - Brian A Atkinson
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, 66045, KS, USA
- Biodiversity Institute, University of Kansas, Lawrence, 66045, KS, USA
| |
Collapse
|
2
|
Coiro M. Embracing uncertainty: The way forward in plant fossil phylogenetics. AMERICAN JOURNAL OF BOTANY 2024; 111:e16282. [PMID: 38334302 DOI: 10.1002/ajb2.16282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 02/10/2024]
Abstract
Although molecular phylogenetics remains the most widely used method of inferring the evolutionary history of living groups, the last decade has seen a renewed interest in morphological phylogenetics, mostly driven by the promises that integrating the fossil record in phylogenetic trees offers to our understanding of macroevolutionary processes and dynamics and the possibility that the inclusion of fossil taxa could lead to more accurate phylogenetic hypotheses. The plant fossil record presents some challenges to its integration in a phylogenetic framework. Phylogenies including plant fossils often retrieve uncertain relationships with low support, or lack of resolution. This low support is due to the pervasiveness of morphological convergence among plant organs and the fragmentary nature of many plant fossils, and it is often perceived as a fundamental weakness reducing the utility of plant fossils in phylogenetics. Here I discuss the importance of uncertainty in morphological phylogenetics and how we can identify important information from different patterns and types of uncertainty. I also review a set of methodologies that can allow us to understand the causes underpinning uncertainty and how these practices can help us to further our knowledge of plant fossils. I also propose that a new visual language, including the use of networks instead of trees, represents an improvement on the old visualization based on consensus trees and more adequately serves phylogeneticists working with plant fossils. This set of methods and visualization tools represents an important way forward in a fundamental field for our understanding of the evolutionary history of plants.
Collapse
Affiliation(s)
- Mario Coiro
- Department of Palaeontology, University of Vienna, Vienna, Austria
- Ronin Institute for Independent Scholarship, Montclair, NJ, USA
| |
Collapse
|
3
|
López-Martínez AM, Schönenberger J, von Balthazar M, González-Martínez CA, Ramírez-Barahona S, Sauquet H, Magallón S. Integrating Fossil Flowers into the Angiosperm Phylogeny Using Molecular and Morphological Evidence. Syst Biol 2023; 72:837-855. [PMID: 36995161 DOI: 10.1093/sysbio/syad017] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/23/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
Fossils are essential to infer past evolutionary processes. The assignment of fossils to extant clades has traditionally relied on morphological similarity and on apomorphies shared with extant taxa. The use of explicit phylogenetic analyses to establish fossil affinities has so far remained limited. In this study, we built a comprehensive framework to investigate the phylogenetic placement of 24 exceptionally preserved fossil flowers. For this, we assembled a new species-level data set of 30 floral traits for 1201 extant species that were sampled to capture the stem and crown nodes of all angiosperm families. We explored multiple analytical approaches to integrate the fossils into the phylogeny, including different phylogenetic estimation methods, topological-constrained analyses, and combining molecular and morphological data of extant and fossil species. Our results were widely consistent across approaches and showed minor differences in the support of fossils at different phylogenetic positions. The placement of some fossils agrees with previously suggested relationships, but for others, a new placement is inferred. We also identified fossils that are well supported within particular extant families, whereas others showed high phylogenetic uncertainty. Finally, we present recommendations for future analyses combining molecular and morphological evidence, regarding the selection of fossils and appropriate methodologies, and provide some perspectives on how to integrate fossils into the investigation of divergence times and the temporal evolution of morphological traits. [Angiosperms; fossil flowers; phylogenetic uncertainty; RoguePlots.].
Collapse
Affiliation(s)
- Andrea M López-Martínez
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Edificio D, 1° Piso, Circuito de Posgrados, Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - Maria von Balthazar
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna 1030, Austria
| | - César A González-Martínez
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico
| | - Santiago Ramírez-Barahona
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico
| | - Hervé Sauquet
- National Herbarium of New South Wales (NSW), Royal Botanic Gardens and Domain Trust, Sydney, NSW 2000, Australia
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Susana Magallón
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico
| |
Collapse
|
4
|
Wilf P, Iglesias A, Gandolfo MA. The first Gondwanan Euphorbiaceae fossils reset the biogeographic history of the Macaranga-Mallotus clade. AMERICAN JOURNAL OF BOTANY 2023; 110:e16169. [PMID: 37128981 DOI: 10.1002/ajb2.16169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 05/03/2023]
Abstract
PREMISE The spurge family Euphorbiaceae is prominent in tropical rainforests worldwide, particularly in Asia. There is little consensus on the biogeographic origins of the family or its principal lineages. No confirmed spurge macrofossils have come from Gondwana. METHODS We describe the first Gondwanan macrofossils of Euphorbiaceae, represented by two infructescences and associated peltate leaves from the early Eocene (52 Myr ago [Ma]) Laguna del Hunco site in Chubut, Argentina. RESULTS The infructescences are panicles bearing tiny, pedicellate, spineless capsular fruits with two locules, two axile lenticular seeds, and two unbranched, plumose stigmas. The fossils' character combination only occurs today in some species of the Macaranga-Mallotus clade (MMC; Euphorbiaceae), a widespread Old-World understory group often thought to have tropical Asian origins. The associated leaves are consistent with extant Macaranga. CONCLUSIONS The new fossils are the oldest known for the MMC, demonstrating its Gondwanan history and marking its divergence by at least 52 Ma. This discovery makes an Asian origin of the MMC unlikely because immense oceanic distances separated Asia and South America 52 Ma. The only other MMC reproductive fossils so far known are also from the southern hemisphere (early Miocene, southern New Zealand), far from the Asian tropics. The MMC, along with many other Gondwanan survivors, most likely entered Asia during the Neogene Sahul-Sunda collision. Our discovery adds to a substantial series of well-dated, well-preserved fossils from one undersampled region, Patagonia, that have changed our understanding of plant biogeographic history.
Collapse
Affiliation(s)
- Peter Wilf
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Ari Iglesias
- Instituto de Investigaciones en Biodiversidad y Medioambiente, Universidad Nacional del Comahue, Consejo Nacional de Investigaciones Científicas y Tecnológicas, San Carlos de Bariloche, Río Negro, R8400FRF, Argentina
| | - María A Gandolfo
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Museo Paleontológico Egidio Feruglio, Consejo Nacional de Investigaciones Científicas y Técnicas, Trelew, Chubut, 9100, Argentina
| |
Collapse
|
5
|
Atkinson BA. Icacinaceae fossil provides evidence for a Cretaceous origin of the lamiids. NATURE PLANTS 2022; 8:1374-1377. [PMID: 36376504 DOI: 10.1038/s41477-022-01275-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 10/10/2022] [Indexed: 05/12/2023]
Abstract
Today the asterids comprise over 80,000 species of flowering plants; however, relatively little is known about the timing of their early diversification. This is particularly true for the diverse lamiid clade, which comprises half of asterid diversity. Here, a lamiid fossil fruit assigned to Icacinaceae from the Campanian of western North America provides important macrofossil evidence indicating that lamiids diverged at least 80 million years ago and sheds light on potential Cretaceous rainforest-like ecosystems.
Collapse
Affiliation(s)
- Brian A Atkinson
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA.
- Biodiversity Institute, University of Kansas, Lawrence, KS, USA.
| |
Collapse
|
6
|
Matel TP, Gandolfo MA, Hermsen EJ, Wilf P. Cunoniaceae infructescences from the early Eocene Laguna del Hunco flora, Patagonia, Argentina. AMERICAN JOURNAL OF BOTANY 2022; 109:986-1003. [PMID: 35567490 DOI: 10.1002/ajb2.1867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/19/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Two distinct types of fossil infructescences from the early Eocene Laguna del Hunco flora, Chubut Province, Patagonia, Argentina, preserve features of the family Cunoniaceae. The goal of the study was to assess their affinities within Cunoniaceae and to interpret their evolutionary and biogeographical significance. METHODS Specimens were collected from the Tufolitas Laguna del Hunco, Huitrera Formation. They were prepared, photographed, and compared morphologically with similar extant and fossil fruits and infructescences using published literature and herbarium material. RESULTS The fruit and infructescence morphology place the fossil taxa within Cunoniaceae. They do not conform to any extant genus, supporting the erection of two new fossil genera. Racemofructus gen. nov. shares diagnostic features of the tribe Cunonieae, especially Weinmannia s.l., and exhibits two tribal morphological synapomorphies: a racemose inflorescence and a replum composed of a single column. Cunoniocarpa gen. nov. specimens are paniculate inflorescences with basipetally dehiscent, bicarpellate capsules that have persistent styles and calyces. Its replum morphology suggests an affinity to the tribe Caldcluvieae, particularly to the genus Ackama. CONCLUSIONS The new Patagonian fossils described herein constitute the oldest record of cunoniaceous capsules globally, supplementing a significant body of fossil evidence from pollen, wood, and reproductive structures from southern South America and Antarctica that suggests that the Cunoniaceae were diversified and widely distributed in the southern hemisphere by the early Eocene. Racemofructus and Cunoniocarpa are, respectively, the first fossil records from South America of reproductive structures with affinity to tribes Cunonieae and Caldcluvieae.
Collapse
Affiliation(s)
- Theodore P Matel
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - María A Gandolfo
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Elizabeth J Hermsen
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Paleontological Research Institution, 1259 Trumansburg Road, Ithaca, NY, 14850, USA
| | - Peter Wilf
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, 16802, USA
| |
Collapse
|