(1985), Labandeira and Sepkoski (1993), Farrell (1998), Labandeira (1998), Danforth and Ascher (1999), Grimaldi (1999), Wilf et al. 2009, Specht and Bartlett 2009, Licausi 2011, Glover 2014, among others). Evidence of arthropod-plant interactions in the Upper Triassic of the Southwestern United States.
All total in this rich flora of some 6,000 species, there are 812 endemic angiosperms and conifers, 12 endemic genera, and one endemic flowering plant family (A. Distant pinnacles and spires are weathered calc-alkaline Miocene andesites known as the Namosi Volcanics (Rodda and Kroenke 1984). (2008), Specht and Bartlett (2009), Dilcher (2010), D. Isoptera (termites) are hemimetabolous insects (Grimaldi and Engel 2005). The insect developmental tool kit is comprised of certain homeotic selector genes (including Hox genes), zygotic (gap- maternal-, and pair-rule-) genes, field-specific selector genes, compartment selector genes, cell-type-specific selector genes, and segment polarity genes; and the TFs they encode (Rosenberg et al. In addition, the insect developmental tool kit is comprised of controlling factors behind the cessation of insect growth including bioactive PTTH, JH, juvenile hormone esterases, and ecdysone steroids (Truman and Riddiford 2002, Nijhout 2003, S. Juvenile hormone biosynthesized in the corpora allata of the insect brain is a sesquiterpenoid epoxide methyl ester (Hartfelder 2000). Key elements of the Drosophila molecular tool kit include: Evolution of the Hox complex. Ice-free terrestrial environments in the Late Silurian were covered in vegetation. Understanding the origin and diversification of holometabolous insects in deep-time.
(2014), have contributed to our knowledge of the origin and evolution of flowering plants. fossil-based, molecular, phylogenetic and paleobiogeographic studies) and current viewpoints about the explosive Cretaceous diversification of angiosperms. Further, problems associated with co-radiations of angiosperms and insects are brought to light by phylogenetics (T. 2007) suggesting that evolution of certain clades of late Mesozoic phytophagous ants, bees, beetles, butterflies, flies, and moths might be independent of the explosive origin and spread of eudicot orders and families (Labandeira 2014). Root Gorelick (2001) challenges the validity of a biotic coevolutionary hypothesis on the origin of flowering plants. Deciphering the ancestry of flowering plants and their paleoecologies probably requires an understanding of the paleontology of "fingerprints of developmental regulation" (quoted from page 723, Sanders et al.
The image was captured in 1981 while the author was visiting Indiana University. both within and outside the paradigm of transcription-encoding factors ..." (page 129, Niklas 2006). The family Degeneriaceae was discovered in 1942 by I. Endress (1994, 2001 [a book chapter and two papers], 2004), Bateman et al. Several developmental gene families, TFs, and enzymes involved in hormone signaling cascades are known in invertebrates based in part, on experimental studies of the Drosophila model arthropod (S. Wings, halteres, arachnid spinnerets, and insect legs are all organs that develop from limb fields of cells where Ubx expression is prevalent (S. Several insect systematists studying beetle (Coleoptera) evolution are employing some genes and proteins of the insect development tool kit in their phylogenetic analyses (Gómez-Zurita and Galián 2005).
The three essays on the succeeding web pages are written from this research perspective. Gómez-Zurita and Galián (2005) discuss the utility of molecular phylogenetic characters appearing in the entomological literature in a review paper, which is organized along the lines of Floyd and Bowman (2007) for land plants (see section below). Understanding the land plant developmental tool kit and gene regulation from a deep time research perspective ties-in with models of cone and floral organization, cell geometry and regulation of growth from SAMs, paleobiology of homeodomain TF trafficking, phyllotaxis, leaf development, and morphogenesis of fertile organs.
The clade probably first appeared during Triassic times, possibly as a result of the re-setting of plant evolutionary history following the devastating global extinction event of the Permian Triassic boundary ..." (4. The fossil dataset used by the Cascales-Miñana team is grossly incomplete. Simply put, paleontologic data are required to calibrate and validate molecular phylogenies (Peterson et al. "The interface of these three subject areas (Figure 1 on Page 778), molecular evolution, evolutionary developmental ('evo-devo') biology, and palaeoecology, is the theme of Molecular Palaeobiology, as it [the approach] uniquely integrates the patterns written in the two historical records, genomic and geological ... Labandeira's findings (2014) might also help disprove the notion of a Hauterivian (Lower Cretaceous) origin of flowering plants (Hughes 1994, Friis et al. Errors in molecular-phylogenetic inference may result from effects of LBA (Barrett and Willis 2001, Magallón 2010, Zhenxiang Xi et al. Paraphyly may be underappreciated (Krassilov 2002, Stuessy 2010) and effects on seed plant evolution attributable to possible HT might cloud our understanding of relationships among basal clades of the angiosperm crown group (Bergthorsson et al. "Darwin himself referred to the 'early origin and diversification of angiosperms' as 'an abominable mystery,' and the origin of the flower- and therefore flowering plants- is still a question ..." (page 86, Pamela S. Soltis 2014) Molecular-phylogenetic analyses by Magallón (page 395, 2010) when calibrated with fossil data and compared with different relaxed-clock methods "... Coevolution between phytophagous insect antagonists and Carboniferous, Permian, and Triassic seed plant hosts at the level of their respective developmental tool kits with focus on selective forces that drive the logic of transcriptional regulation is proposed to explain the origin of angiosperms and certain clades of holometabolous insects.
Modern syntheses on the abominable mystery of the origin of angiosperms from unknown Paleozoic seed plant ancestors and modern radiations are published by Frohlich and Chase (2007), Maheshwari (2007), Sokolov and Timonin (2007), Zavada (2007), J. After integrating evidence as a whole with our results, the resulting scenario suggests that there is nothing particularly mysterious about the diversification of angiosperms during Cretaceous times or how it is reflected in the fossil record. The preceding statement is an optimistic appraisal of methodology used by Cascales-Miñana et al. Some "current viewpoints" are left out of the analysis. The preceding statement is from page 35 of Armen Takhtajan (1969), Flowering Plants: Origin and Dispersal (translated by C. Conrad Labandeira is apparently less than enthusiastic on the idea of a coevolutionary origin of the group (2014). "Tight coevolution" between animal disperser and plant was probably rare (page 3, Tiffney 2004). 2007) expressed as often disarticulated and shed, wood-, pollen-, seed-, foliar-, and cone- and floral- organs preserved in the fragmentary rock record of the Carboniferous, Permian, and Triassic periods.
Some of the historical syntheses include Arber and Parkin (1907), I. Bailey (1949), Edgar Anderson (1934), Axelrod (1952, 1970), Leppik (1960, 1968), Raven and Kyhos (1965), Cronquist (1968), Thorne (1968), Melville (1969), Takhtajan (1969, 1976, 1991), Raven and Axelrod (1974), Stebbins (1958, 1974), C. Beck (1976), Hughes (1976, 1994), Meeuse (1979), Nair (1979), Krassilov (1977), Retallack and Dilcher (1981 [two papers]), Asama (1982, 1985), Melville (1983), Crane (1985), Meyen (1986, 1988), Dilcher (1986, 2000), J. Doyle and Donoghue (1986, 1987), Endress (1987), Friis et al. If the answer to the preceding question is "yes," how does this evo-devo mechanism affect arthropod antagonist body allometries and population ecology? Further, the evo-devo of flight is yet another conundrum in paleoentomology (Grimaldi and Engel 2005). Poleward migration of early angiosperm flora - angiosperms only displaced the relict Jurassic-type flora at high latitudes in late Cretaceous time.
(2017) compile particularly relevant reference lists. Flowering material of Degeneria vitiensis is shown in the right-hand image (photographed by Paddy Ryan, Ph. Fragrance of this species resembles Cananga odorata according to Professor Al Smith (A. While discussing the effects of ice-house/hot house planetary climatic switches on expansion of land plant invertebrate herbivores Labandeira (2006) states: "One possibility is that these atmospheric variables have direct physiologic consequences on the selection and turnover of particular plant clades globally, which in turn elicit an associational response from selected clades of insect herbivores." The preceding statement is quoted from page 425 of C. Labandeira (2006), The four phases of plant-arthropod associations in deep time, Geologica Acta 4(4): 409-438. Additional compilations on the origin of angiosperms and floral morphology include Krassilov (1991), Thorne (1992), Endress (1993, 2001 [a book chapter and two papers], 2004), Friedman (1992 [two papers]), Stewart and Rothwell (1993), Nixon et al. Studies on Drosophila melanogaster eggs, specifically, artificial size-selection experimentation, affects larval patterning and body allometry (Miles et al. Do host seed plant brassinolides and other hormones affect insect antagonist egg size, potentially controlling larval tissue patterning? At the very earliest, flying insects were known from the Devonian Period. Doyle (1991, 2000), Frohlich and Parker (2000), Friedman and Floyd (2001), G. The evo-devo research perspective could help us decipher more than 400 million years of insect and seed plant evolution and the enigmatic origins of flowering plants and interacting Holometabola. (2014), and Tomescu (2016), among others, are useful in understanding the developmental systems of animals, fungi, and plants. Several neurosecretory hormones play an important part in mechanisms that regulate cell division and growth including insulin-like peptides (Drosophila insulin-like proteins [DILPs] and bombyxins), chitenase-derived imaginal disk factor proteins, the steroid hormone ecdysone, local autocrine and paracrine TFs, and brain neurosecretory prothoracicotropic hormone (PTTH) (Nijhout 2003). Evolutionary-development of arthropod- and plant organs and molecular tool kits is "highly dynamic in evolutionary time" involving the evolution of cis-acting promoters (page 83, Baum 1998). Reviews by Rothwell (1987), Arthur (2002), Meyerowitz (2002), Becker and Theißen (Figure 1, page 468, 2003), Niklas (2006), Rothwell et al. A key paper on the control of insect body size by Nijhout (2003) outlines the molecular mechanisms involving cis-acting TFs and hormones and environmental controls (nutrition and temperature) behind growth and cell division in hemimetabolous and holometabolous insects. The image above is the northwestern face of the Korombasabasaga Range, Viti Levu Island, Fiji as viewed from the road between Namosi and Wainimakutu villages. A review of neotenous development in termites is available (Korb and Hartfelder 2008). Structurally similar to bioactive plant brassinosteroids, 20E-ecdysone induces a cascade of TF biosynthesis important in the regulation of insect development (Truman and Riddiford 2002, De Loof 2008). One line of paleobiological thinking hypothesizes that insects took flight to exploit new habitat. Did ingestion of seed plant brassinosteroids by pterygote insects affect the evo-devo of wings from thoracic limb pads and JH signaling? The evo-devo of insect caste polyphenism is reviewed by Emlen and Nijhout (2000). Thummel and Chory (2002) point to a possible coevolutionary connection between the 20E-ecdysone/cytochrome P biosynthetic machinery of insect antagonists and seed plant hosts. Further, changes in the arthropod homeodomain and evolution of new protein motifs led to new Hox developmental tool kit functions in certain insect lineages (S. The paleobiology of insect flight in relation to the advent of arthropod-seed plant mutualisms remains unexplained. Erbar (2007) summarizes past ideas on a supposed Mesozoic origin of angiosperms from the research perspective of evolutionary-development (evo-devo). Retallack and Dilcher (1981) presented in-depth discussion of Melville's ideas on a glossopterid ancestry of the angiosperms including a reanalysis of glossopterid fructifications. Others suggest that flowering plants evolved from multiple, unrelated seed plant lineages (Edgar Anderson 1934). 2002) and Nair's Triphyletic Theory (Nair 1979) are best placed in this paragraph. Eichler (1976) proposed that unisexual gymnosperms may be the ancestors of angiosperms. Finally the column labeled "Paraphyly or Polyphyly" denotes whether the scientific paper in question attributes the origin of flowering plants to a natural, intergeneric hybridization event, allopolyploidy, or events that brought together two or more distinct lines of seed plant evolution. Doyle and Donoghue 1986, 1987) and classic research by Arber and Parkin (1907), Edgar Anderson (1934), Axelrod (1952), Ehrlich and Raven (1964), Raven and Kyhos (1965), Takhtajan (1969, 1976), and Raven (1977), dovetail with- and potentially support a coevolutionary hypothesis on the origin of flowering plants, which is developed on the following pages of the web site for purposes of classroom and seminar debate and discussion. Doyle 2008) of perianth parts, microsporophylls, and megasporophylls to form a flower was an improbable and unnecessarily complicated saltational event punctuating a long and gradual evolutionary history of angiosperms. Simply put, massive, shortened bisexual cone axes bearing megasporophylls, laminar microsporophylls, and spirally-arranged foliar tepals, probably existed in populations of poorly understood Paleozoic seed plants described as gigantopteroids and Vojnovskyales, groups omitted by J. Doyle and others in their many published phylogenetic analyses.