DOCSLIB.ORG

Archaefructus – Angiosperm Precursor Or Specialized Early Angiosperm?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Archaefructus – Angiosperm Precursor Or Specialized Early Angiosperm? Opinion TRENDS in Plant Science Vol.8 No.8 August 2003 369 Archaefructus – angiosperm precursor or specialized early angiosperm? Else Marie Friis1, James A. Doyle2, Peter K. Endress3 and Qin Leng4 1Department of Palaeobotany, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden 2Section of Evolution and Ecology, University of California, Davis, CA 95616, USA 3Institute of Systematic Botany, University of Zurich, 8008 Zurich, Switzerland 4Nanjing Institute of Geology and Palaeontology, CAS, 39 East Beijing Road, 210008 Nanjing, The People’s Republic of China With molecular analyses indicating that angiosperms Ovulate and microsporangiate organs are not closely related to any other extant seed plant Reproductive axes are elongate with ovulate organs borne group, information from fossils might provide the only distally and microsporangiate organs borne proximally. basis for reconstructing their origin. Therefore the Some specimens apparently have unisexual (ovulate) axes. description of a new Early Cretaceous angiosperm, The organs are crowded in young specimens (Fig. 1a) but Archaefructus, placed as the sister of all extant angio- spaced out in more mature specimens (Fig. 1b). Ovulate sperms, has created much debate and optimism. organs are pedicellate and typically borne in pairs on each However, we question both the interpretation and the pedicel (Fig. 2). They are elongate with an acuminate apex analysis of Archaefructus, concluding that it might be a and enclose few (A. liaoningensis) or many (A. sinensis) crown-group angiosperm specialized for aquatic habit ovules or seeds. rather than a more primitive relative. Although ovulate organs of Archaefructus have not been shown to have all the features of carpels, in other The family Archaefructaceae [1] was established to respects they are more like angiosperm carpels than they accommodate two extinct species, Archaefructus liaonin- are like the ovulate organs of other seed plants with gensis [2] and Archaefructus sinensis [1], from the Yixian enclosed ovules (Box 2). However, it is not clear that they Formation in northeastern China. In the initial report [2], were conduplicate (i.e. like a leaf folded lengthwise and A. liaoningensis was presented as the oldest known sealed along its margins), or that the fruits were follicles, angiosperm because the beds were dated as Late Jurassic. as described by Sun et al. [1,2]. Follicles open long- However, radiometric dating strongly supports a mid- itudinally along the ventral side. No such open fruits and Early Cretaceous age for the Yixian Formation [3], close to the age of the first records of angiosperms in other areas (Box 1). Box 1. Age and palaeoenvironment of Archaefructus The Archaefructaceae were defined as including small The Archaefructus fossils were all collected in the Yixian Formation, herbaceous water plants with axillary branches terminat- outcropping in the western part of Liaoning Province in northeastern ing in reproductive organs, and with strongly dissected China. The Yixian Formation is part of the Jehol Group, which has yielded a wealth of exquisitely preserved fossil animals, most leaves. Reproductive axes were assumed to be exposed notably feathered theropod dinosaurs and a diversity of early above water level and were described as solitary flowers birds. The sediments were deposited in a low-energy lacustrine without perianth, with numerous stamens borne in environment in a seasonally semiarid climate and are intercalated helically arranged pairs and numerous conduplicate with volcanic tuffs and basalts (the environment and biota are reviewed in Ref. [3]). Although the faunal elements of the Jehol biota carpels borne in a helical or whorled arrangement and exhibit exceptional preservation, the plant fossils rarely have cellular maturing into multi-seeded follicles. details intact, and tissues are often replaced or infilled with pyrite Ge Sun et al. [1] evaluated the phylogenetic position of framboids and microcrystallines [33]. However, some fossil plants Archaefructus by including its morphological characters in have been preserved with many of the organs (roots, stems, leaves) still in organic connection. This is unusual for Cretaceous plant a combined three-gene molecular and morphological fossils and provides unique information about growth form in early analysis, which placed Archaefructus as the sister to angiosperms. The only contemporaneous flora with whole-plant extant angiosperms. We will discuss the characters of preservation is the Crato flora from the Early Cretaceous of Brazil, Archaefructus in detail and question aspects of their deposited in a similar low-energy lake system [34]. The thickness of the Yixian Formation reaches 4700 m, with plant interpretation. Our conclusions are based on published and animal fossils occurring throughout. The age of the Yixian descriptions and illustrations [1,2,4] and our own studies Formation has been much debated [35] but there is now strong of additional specimens housed in the Institute of evidence from radiometric dating that it is Early Cretaceous [3,36–38]. Vertebrate Paleontology and Paleoanthropology, CAS, The oldest Archaefructus is from the Jianshangou Bed, which is in the lower part of the Yixian Formation and dated radiometrically to Beijing, China. ,125 million years, corresponding to the Barremian stage [3], close to the age of the first well-known angiosperm floras Corresponding author: Else Marie Friis ([email protected]). elsewhere [31,39]. http://plants.trends.com 1360-1385/03/$ - see front matter q 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S1360-1385(03)00161-4 370 Opinion TRENDS in Plant Science Vol.8 No.8 August 2003 Box 2. Reproductive structures of Caytonia and angiosperms Several non-angiospermous Mesozoic seed plants resemble Archae- fructus and extant angiosperms in having enclosed ovules, but their enclosing structures clearly differ from carpels or are poorly under- stood. The best examples are Caytonia (Caytoniales, a ‘Mesozoic pteridosperm’ [16]), Irania (related to Czekanowskiales? [40]), and Leptostrobus (Czekanowskiales [41]). Caytoniales were first described by Hamshaw Thomas [42] from Yorkshire (UK) as Jurassic angiosperms, but later Tom Harris [16] documented that Caytonia had gymnospermous reproduction, with pollen germinating inside the micropyles of the ovules. Subsequently, the homology of the ovule-bearing structures (‘cupules’) with carpels was questioned. The cupules appear to be borne in two rows on a bilateral axis, like leaflets on the rachis of a compound leaf, unlike carpels, which are borne like leaves on a radial stem. Caytonia cupules are circinately curved toward the axis; their plane of symmetry is perpendicular to the axis, and ovules form an arc perpendicular to this plane of symmetry. By contrast, the ovulate structures of Archaefructus are elongate and acuminate, their plane of symmetry is parallel to the axis, and ovules are attached parallel to the plane of symmetry – typical features of carpels. Leptostrobus also has ovulate organs arranged along an axis. They consist of two valves, but each valve seems to differ from a carpel in its symmetry and in bearing ovules in an arc perpendicular to its plane of symmetry [41]. Irania also has paired ovulate organs borne along an axis [40], but the detailed structure of the organs is unknown and a more detailed comparison is not possible. Fig. 1. Line drawings showing details of the reproductive organs of Archaefructus The ovules of Caytonia have only one integument, rather than two, sp. (a) and Archaefructus liaoningensis (b,c) from the Early Cretaceous Yixian For- the ancestral state in angiosperms [17]. Sun et al. [2] described ovules mation of northeastern China. (a) Immature reproductive axis with densely spaced of Archaefructus as bitegmic and anatropous (with two integuments ovulate organs (carpels). (b) Mature reproductive axes with carpels above (ovulate and a reflexed orientation), but unfortunately their structure is zone) and microsporangiate organs (stamens) below (staminate zone). (c) Basal part of a mature reproductive axis showing clustering of the stamens in the stami- uncertain. Even in well-preserved specimens (B0112, Fig. 2) we failed nate zone; a few carpels of the ovulate zone are also shown. The paired arrange- to establish the number of integuments, nature of internal structures, ment of both the carpels and stamens is evident in several places (arrow heads). or orientation and attachment of ovules. Scale bar ¼ 1 cm. (a) Redrawn from Plate 32, Fig. 6, in Ref. [4]; (b) redrawn from Because they both have four microsporangia, stamens of Plate 32, Fig. 3 in Ref [4]; (c) redrawn from Plate 31, Fig. 1, in Ref [4]. angiosperms have often been compared with the synangia of Caytoniales (Caytonanthus) [42]. These are borne in groups on lateral stalks along an axis. The stalks often branch several times, but occasionally there are only two or three synangia grouped closely on an unbranched stalk, suggesting the arrangement in Archaefructus. However, Caytonanthus synangia are radial structures with four equally spaced microsporangia, rather than bilateral structures with (a) (b) two pairs of sporangia on either side of a sterile connective, like angiosperm stamens. Ovulate zone Caytonia has figured in discussions of angiosperm origin, but with the cupules interpreted as homologous with the bitegmic ovules of angiosperms, not with the carpels [12,14,43–46]. no dehiscence line were observed. Even in living material
Load more

Recommended publications
  • Etude Sur L'origine Et L'évolution Des Variations Florales Chez Delphinium L. (Ranunculaceae) À Travers La Morphologie, L'anatomie Et La Tératologie
    Etude sur l'origine et l'évolution des variations florales chez Delphinium L. (Ranunculaceae) à travers la morphologie, l'anatomie et la tératologie : 2019SACLS126 : NNT Thèse de doctorat de l'Université Paris-Saclay préparée à l'Université Paris-Sud ED n°567 : Sciences du végétal : du gène à l'écosystème (SDV) Spécialité de doctorat : Biologie Thèse présentée et soutenue à Paris, le 29/05/2019, par Felipe Espinosa Moreno Composition du Jury : Bernard Riera Chargé de Recherche, CNRS (MECADEV) Rapporteur Julien Bachelier Professeur, Freie Universität Berlin (DCPS) Rapporteur Catherine Damerval Directrice de Recherche, CNRS (Génétique Quantitative et Evolution Le Moulon) Présidente Dario De Franceschi Maître de Conférences, Muséum national d'Histoire naturelle (CR2P) Examinateur Sophie Nadot Professeure, Université Paris-Sud (ESE) Directrice de thèse Florian Jabbour Maître de conférences, Muséum national d'Histoire naturelle (ISYEB) Invité Etude sur l'origine et l'évolution des variations florales chez Delphinium L. (Ranunculaceae) à travers la morphologie, l'anatomie et la tératologie Remerciements Ce manuscrit présente le travail de doctorat que j'ai réalisé entre les années 2016 et 2019 au sein de l'Ecole doctorale Sciences du végétale: du gène à l'écosystème, à l'Université Paris-Saclay Paris-Sud et au Muséum national d'Histoire naturelle de Paris. Même si sa réalisation a impliqué un investissement personnel énorme, celui-ci a eu tout son sens uniquement et grâce à l'encadrement, le soutien et l'accompagnement de nombreuses personnes que je remercie de la façon la plus sincère. Je remercie très spécialement Florian Jabbour et Sophie Nadot, mes directeurs de thèse.
    [Show full text]
  • From the Yixian Formation in Northeastern China
    An early infructescence Hyrcantha decussata (comb. nov.) from the Yixian Formation in northeastern China David L. Dilcher*†, Ge Sun†‡, Qiang Ji§, and Hongqi Li¶ *Florida Museum of Natural History, University of Florida, Gainesville, FL 32611; ‡Research Center of Paleontology, Jilin University, Changchun 130026, China; §Geological Institute of Chinese Academy of Geosciences, Beijing 100037, China; and ¶Department of Biology, Frostburg State University, Frostburg, MD 21532 Contributed by David L. Dilcher, April 16, 2007 (sent for review November 10, 2006) The continuing study of early angiosperms from the Yixian For- about half their length. Each carpel containing 10–16 anatrop- mation (Ϸ125 Ma) of northeastern China has yielded a second early ous ovules/seeds borne along an adaxial linear placentae. angiosperm genus. This report is a detailed account of this early flowering plant and recognizes earlier reports of similar fossils H. decussata (Leng et Friis) Dilcher, Sun, Ji et Li comb. nov. from Russia and China. Entire plants, including roots, stems, and Synonymy. S. decussatus Leng et Friis, 2003, 2006. branches terminating in fruits are presented and reconstructed. Emended Description. Plant erect, 20–25 cm tall, with predomi- Evidence for a possible aquatic nature of this plant is presented. nately alternate branching of 30–45°, rarely ternate branching The relationship of Hyrcantha (‘‘Sinocarpus’’) to the eudicots is three to four times (Fig. 1A). Main axis 2.2–2.5 mm wide and discussed. The presence of this second early angiosperm genus, lightly striated alternate branches 1–1.2 mm wide. Lower now known as a whole plant, is important in the discussion of its branches with dilated nodes ensheathed by a thin ocrea (Fig.
    [Show full text]
  • UC Davis UC Davis Previously Published Works
    UC Davis UC Davis Previously Published Works Title Integrating early Cretaceous fossils into the phylogeny of living angiosperms: Anita lines and relatives of Chloranthaceae Permalink https://escholarship.org/uc/item/3bj1s569 Journal International Journal of Plant Sciences, 175(5) ISSN 1058-5893 Authors Doyle, JA Endress, PK Publication Date 2014 DOI 10.1086/675935 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Int. J. Plant Sci. 175(5):555–600. 2014. ᭧ 2014 by The University of Chicago. All rights reserved. 1058-5893/2014/17505-0006$15.00 DOI: 10.1086/675935 INTEGRATING EARLY CRETACEOUS FOSSILS INTO THE PHYLOGENY OF LIVING ANGIOSPERMS: ANITA LINES AND RELATIVES OF CHLORANTHACEAE James A. Doyle1,* and Peter K. Endress† *Department of Evolution and Ecology, University of California, Davis, California 95616, USA; and †Institute of Systematic Botany, University of Zurich, 8008 Zurich, Switzerland Editor: Patrick S. Herendeen Premise of research. Discoveries of fossil flowers in Cretaceous rocks offer improved evidence for rela- tionships with living clades, but for more secure inferences formal phylogenetic analyses are desirable. We extend previous analyses of magnoliids, monocots, and basal eudicots to Aptian, Albian, and Cenomanian fossils related to the basal “ANITA” lines and Chloranthaceae. Methodology. We performed parsimony analyses of a morphological data set of Recent angiosperms and published fossils, with the arrangement of Recent taxa constrained to backbone trees based primarily on molecular data. Pivotal results. Not only Monetianthus (as previously inferred) but also Carpestella is nested within Nymphaeaceae, while Pluricarpellatia may be a stem relative of Cabombaceae or Nymphaeaceae. Anacostia (with Similipollis pollen) is nested within Austrobaileyales.
    [Show full text]
  • Water Lilies As Emerging Models for Darwin's Abominable Mystery
    OPEN Citation: Horticulture Research (2017) 4, 17051; doi:10.1038/hortres.2017.51 www.nature.com/hortres REVIEW ARTICLE Water lilies as emerging models for Darwin’s abominable mystery Fei Chen1, Xing Liu1, Cuiwei Yu2, Yuchu Chen2, Haibao Tang1 and Liangsheng Zhang1 Water lilies are not only highly favored aquatic ornamental plants with cultural and economic importance but they also occupy a critical evolutionary space that is crucial for understanding the origin and early evolutionary trajectory of flowering plants. The birth and rapid radiation of flowering plants has interested many scientists and was considered ‘an abominable mystery’ by Charles Darwin. In searching for the angiosperm evolutionary origin and its underlying mechanisms, the genome of Amborella has shed some light on the molecular features of one of the basal angiosperm lineages; however, little is known regarding the genetics and genomics of another basal angiosperm lineage, namely, the water lily. In this study, we reviewed current molecular research and note that water lily research has entered the genomic era. We propose that the genome of the water lily is critical for studying the contentious relationship of basal angiosperms and Darwin’s ‘abominable mystery’. Four pantropical water lilies, especially the recently sequenced Nymphaea colorata, have characteristics such as small size, rapid growth rate and numerous seeds and can act as the best model for understanding the origin of angiosperms. The water lily genome is also valuable for revealing the genetics of ornamental traits and will largely accelerate the molecular breeding of water lilies. Horticulture Research (2017) 4, 17051; doi:10.1038/hortres.2017.51; Published online 4 October 2017 INTRODUCTION Ondinea, and Victoria.4,5 Floral organs differ greatly among each Ornamentals, cultural symbols and economic value family in the order Nymphaeales.
    [Show full text]
  • Archaefructaceae, a New Basal Angiosperm Family
    See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/11380880 Archaefructaceae, a New Basal Angiosperm Family Article in Science · June 2002 DOI: 10.1126/science.1069439 · Source: PubMed CITATIONS READS 389 736 6 authors, including: Ge Sun David L Dilcher Jilin University Indiana University Bloomington 59 PUBLICATIONS 1,419 CITATIONS 393 PUBLICATIONS 13,765 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Nature and Time on Earth - Project for a course and a book for virtual visits to past environments in learning programmes for university students (coordinators Edoardo Martinetto, Emanuel Tschopp, Robert A. Gastaldo) View project NECLIME - Neogene Climate Evolution in Eurasia View project All content following this page was uploaded by David L Dilcher on 23 May 2014. The user has requested enhancement of the downloaded file. Archaefructaceae, a New Basal Angiosperm Family Ge Sun; Qiang Ji; David L. Dilcher; Shaolin Zheng; Kevin C. Nixon; Xinfu Wang Science, New Series, Vol. 296, No. 5569. (May 3, 2002), pp. 899-904. Stable URL: http://links.jstor.org/sici?sici=0036-8075%2820020503%293%3A296%3A5569%3C899%3AAANBAF%3E2.0.CO%3B2-B Science is currently published by American Association for the Advancement of Science. Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use.
    [Show full text]
  • First Flower 1 Have Students Bring in Flowering Plants and Distribute Them Among Groups
    Original broadcast: April 17, 2007 BEFORE WATCHING First Flower 1 Have students bring in flowering plants and distribute them among groups. Ask students what the flower is for (seed formation leading PROGRAM OVERVIEW to plant reproduction). On the NOVA presents the search for the first board, draw and label the parts of a flower. Make a chart with each flowering plant. part’s function. Have students locate the following parts on their The program: flowers: anther and filament • recounts how one scientist discovered (stamen); the stigma, style, and what might be the first flowering plant ovary (pistil); and the petals fossil, Archaefructus liaoningensis. (corolla). Discuss differences in • follows the search for evidence of the first flowering plants in the reproduction between flowering and non-flowering plants. Hengdaun Mountains of China, the most biodiverse temperate forest in the world. 2 Organize students into three • states that mosses, pines, and firs dominated the Earth for 300 groups. As students watch the program, have each group take million years until flowering plants became prevalent—but how and notes on one of the following: the when this change occurred is a mystery. geography and ecology of the area • shows how flowering plants flower and produce the new featured in China; the technologies, generation—fruit—that allows the plant to adapt to a different set materials, and procedures used to study and date plant findings; and of circumstances. plant classification. • shows how Archaefructus’ separate pollen-producing organs and female organs may have evolved to be joined. • recounts the journey and discoveries of early 1900s botanist AFTER WATCHING Ernest H.
    [Show full text]
  • Spermatophyta Timetree, Accelerated Base Substitution Rates at Mid
    Spermatophyta timetree, accelerated base substitution rates at mid-Cretaceous and the Recent Soichi Osozawa1, Cunio Nackejima2, and john Wakabayashi3 1KawaOso Molecular Bio-Geology Institute 2Japanese Society for Plant Systematics 3California State University, Fresno September 11, 2020 Abstract We constructed a whole of Spermatophyta timetree by employing BEAST v1. X applying the nuclear ribosomal ITS, and chloroplastic matK and rbcL. Robust multipoint calibrations were done by applying fossil ages up to the Jurassic for 20 genera and a Quaternary geological event age of 1.55 Ma for 6 genera. The resultant topology was concordant to the APG system, and we successfully and precisely dated the phylogeny. Through the BEAST analyses, we discovered the exponential increase in base substitution rate in recent geologic time, and suggested that a potential cause was generation of C4 plants and the triggered Quaternary climatic change. The raised rate might have resulted in the increasing of Spermatophyta diversity including endemic Asarum and Viola species. Another rise of base substitution rate was found around 120 Ma, reflecting the order level radiation and diversification of Angiospermae at the middle Cretaceous time. Introduction A goal of botany may be the correlation of botanical evolutionary events with the timeline of Earth history (Wilf & Escapa, 2015). We prepared a Bayesian inference (BI) tree constructed using the latest and the most advanced version of BEAST (v1. X; Suchard et al ., 2018), because a credible timetree of Spermatophyta have not been constructed to date probably by employing the old version and by the unpractical use of functions (Smith et al ., 2010; Beulieu et al ., 2015).
    [Show full text]
  • This Might Be the First Flowering Plant in Earth's History the Plant Grew 125 to 130 Million Years Ago
    This Might Be the First Flowering Plant in Earth's History The plant grew 125 to 130 million years ago Indiana University scientist David Dilcher and fellow paleobotanists at research institutes in Europe believe to have found the first flowering plant ever to grow on Earth. Well, either that or at least one of the earliest ever documented. The newly identified species, named Montsechia vidalii and described in a study published in the journal Proceedings of the National Academy of Science this Monday, grew on our planet around 125 to 130 million years ago. Interestingly, it didn't really produce flowers According to David Dilcher and his colleagues, Montsechia vidalii was an aquatic plant, its preferred habitat freshwater lakes in present-day Spain. Based on fossil evidence, the researchers suspect the plant was a dominant species in these bodies of water. What's interesting is that, although an angiosperm, i.e. a fruiting plant, the now extinct Montsechia vidalii did not produce flowers per se. Rather, it managed to form the fruits containing its seeds without having to first bloom. “Montsechia possesses no obvious 'flower parts,' such as petals or nectar-producing structures for attracting insects, and lives out its entire life cycle under water,” researcher David Dilcher said in an interview, as cited by Phys Org. The reason the paleobotanists are describing Montsechia vidalii as one of the earliest flowering plants on Earth - if not the first ever - is because, to biologists, all plants that deliver their seeds inside fruits count as flowering ones. Mind you, the plant has competition to the title David Dilcher and his colleagues might like to think of Montsechia vidalii as the earliest angiosperm ever to grown and breed on Earth, but the fact of the matter is there are other contender to this title.
    [Show full text]
  • By Tom Bennett and Ottoline Leyser, Plant Molecular Biology 60 (2006) 843–854
    Plant Mol Biol (2006) 62:481–482 DOI 10.1007/s11103-006-9052-8 LETTER TO THE EDITOR Comment on ‘‘Something on the side: axillary meristems and plant development.’’ by Tom Bennett and Ottoline Leyser, Plant Molecular Biology 60 (2006) 843–854 Alexandru M. F. Tomescu Received: 16 June 2006 / Accepted: 7 July 2006 / Published online: 29 August 2006 Ó Springer Science+Business Media B.V. 2006 Depending on the system of classification adopted, the molecular biology, and it could be argued that refer- diversity of living plants is unevenly distributed be- ence to flowering plants was implicit. However, this tween 10 and 12 phyla. At least six extinct phyla are also illustrates the pervasiveness of the reductionist added to these to complete the image that we have paradigm. This paradigm has its virtues and has led to presently of the overall systematic diversity of the important discoveries in many fields of plant biology, organisms classified as land plants or embryophytes. but as scientists we always have to keep in mind the Among these, true axillary meristems are known only whole picture and to be aware what proportion of this in five living (plus two extinct) phyla that comprise the picture is influenced by our data, in order to draw the spermatophytes (seed plants), so from the point of most meaningful inferences. We also have to realize view of systematic diversity most of the organisms we how important it is to use a finer filter when it comes to call plants do not produce axillary meristems. In their deciding when and where the reductionist paradigm is comprehensive and up-to-date review of the mecha- appropriate.
    [Show full text]
  • Stratigraphy, Correlation, Depositional Environments, and Cyclicity of the Early Cretaceous Yixian
    Palaeogeography, Palaeoclimatology, Palaeoecology 464 (2016) 110–133 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Stratigraphy, correlation, depositional environments, and cyclicity of the Early Cretaceous Yixian and ?Jurassic-Cretaceous Tuchengzi formations in the Sihetun area (NE China) based on three continuous cores Yaqiong Wang a,PaulE.Olsenb, Jingeng Sha c,⁎, Xiaogang Yao c, Huanyu Liao c, Yanhong Pan a,SeanKinneyb, Xiaolin Zhang d, Xin Rao c a Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China b Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10968, USA c State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China d Chinese Academy of Sciences Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China article info abstract Article history: Three continuous cores acquired in the Sihetun area of Liaoning Province, famous for feathered non-avian Received 6 March 2016 dinosaurs of the Jehol Biota, reveal the stratigraphic and facies relationships of the divisions of the Early Received in revised form 24 June 2016 Cretaceous Yixian and underlying ?Jurassic-Early Cretaceous Tuchengzi formations. Based on these cores,
    [Show full text]
  • The Remarkable Fossils from the Early Cretaceous Jehol Biota of China and How They Have Changed Our Knowledge of Mesozoic Life
    The remarkable fossils from the Early Cretaceous Jehol Biota of China and how they have changed our knowledge of Mesozoic life Presidential Address, delivered 2nd May 2008 Michael J. Benton1, Zhou Zhonghe2, Patrick J. Orr3, Zhang Fucheng2 & Stuart L. Kearns1 BENTON, M. J., ZHOU Z., ORR, P. J., ZHANG, F. & KEARNS, S. L. 2008. The remarkable fossils from the Early Cretaceous Jehol Biota of China and how they have changed our knowledge. Proceedings of the Geologists’ Association, 119, 209–228. Palaeontologists and others have been repeatedly amazed by reports of spectacularly well-preserved fossils from China, and one of the key sources has been the Jehol Biota of Liaoning, Hebei and Inner Mongolia in NE China. The Jehol Biota consists of three main horizons, the Dabeigou, Yixian and Jiufotang formations, spanning the late Hauterivian to early Aptian (131–120 Ma) of the Early Cretaceous and, collectively, these have produced thousands of essentially complete specimens of plants, insects, aquatic invertebrates, fishes, frogs, salamanders, turtles, lizards, choristoderes, pterosaurs, dinosaurs, birds and mammals. Most of the specimens show some aspect of exceptional preservation, ranging from clear impressions of the body outlines to traces of soft tissues (liver, teleost air sac, eye spots) and external body coverings (scales, feathers, hair). The claim was made that these discoveries have revolutionized our understanding of evolution through this critical part of the Cretaceous Terrestrial Revolution. Key insights have come from the numerous specimens of dinosaurs with feathers, but numerical study shows that only the finds of birds and mammals have substantially changed our views about global diversity and patterns of evolution through the Early Cretaceous.
    [Show full text]
  • What Is Flower
    J. Indian bot. Soc. Vol. 89 (1 & 2) 2010 : 1-14 WHAT IS FLOWER C.M.GOVIL Department of Botany, C.C.S. University, Meerut Secret of success of flowering plants is the presence of well developed sexual reproductive organs in the form of flower and mechanism of cross-pollination. Their sudden appearance in Cretaceous rapid evolution and diversification in short period is puzzling. A large population of early angiosperms has become extinct and many modern species having disappeared more or less completely from their original home land , have occupied large tracts of altogether new areas. Charles Darwin (1959) commented that development and evolution of flowering plants is “An abominable Mystery” This phrase has become a symbol of a key gap in our understanding of plant evolution. Various problems related to flowers are, how ancient flower is; what is its cradle home; how an ancient flower looks like; who are their immediate ancestors; what is the morphological nature of flower and its organs; nature and morphology of placentation; evocation of flower and evolution of flower from simple to complex flower, etc. Answer to all these questions are searched in studying the comparative morphology, fossil records, cladistic studies with the aid of computation and molecular analysis of living plants. The discovery of fossil flower Archaefructus lianingensis (Sun et al. 1998) from Jixin province of North- East China belonging to Jurassic or early Cretaceous strata, estimated about 145 million years old has solved the problems to some extent. This flower is so far the oldest discovered fossil remain and it resembles the primitive extant flower of Magnolia.
    [Show full text]