Flowers

• Angiosperms


  • Evolved from seed plants
  • Not an extant group
  • Caytonia is a possible precursor
• Gnetophytes


  A group of seed plants including Ephedra
• Bennettites


  Mesozoic seed plants superficially resembling cycads
• Kalligrammatid lacewing

  • Middle Jurassic (160Mya)
• Kalligrammatid lacewing

  Convergent evolution with modern butterflies
• Gnetales


  A group of seed plants, sister to Conifers
• Caytonia


  A Middle Jurassic seed plant, possible angiosperm ancestor
• Sagenopteris


  • Leaf of Caytonia with reticulate venation and palmate leaf shape
• Ornithopod grazers


  • Early Cretaceous, e.g. Iguanodon
• High gas production in dinosaurs = high nutritional content
• Sporivory


  Feeding on spores
• Pollinivory


  Feeding on pollen
• Insect pollination


  Complex plant-pollinator interactions already set up
• Bennettites


  • Pollinated by lacewings and beetles
• Reward for pollinators


  Pollen, pollen drop, nutritious ovular tissue
• Ephedra pollinator


  Nectar-feeding moth
• Angiosperm anatomy


  • Fusion of organs (e.g. floral tubes)
  • Clustering of flowers into groups
  • Reduction of perianth = more effective insect pollination
  • Extreme end: orchids
• Apidae (bees) evolve relatively late within Hymenoptera
• Whether true coevolution can be evoked depends on what taxonomic level you analyse the data
• Angiosperm revolution had a Cretaceous origin, but molecular clocks may suggest earlier diversification
• Angiosperms


  • Evolved from seed plants
  • Not an extant group
  • Caytonia is a possible precursor
• Angiosperms underwent an extraordinary radiation and diversification, becoming dominant by the End-Cretaceous
• Gnetophytes


  A group of seed plants including Ephedra
• Bennettites


  Mesozoic seed plants superficially resembling cycads
• Kalligrammatid lacewing


  • Middle Jurassic (160Ma)
• Kalligrammatid lacewing


  Convergent evolution with modern butterflies
• Gnetales


  A group of seed plants, sister to Conifers
• Caytonia


  A Middle Jurassic seed plant, possible angiosperm ancestor
• Sagenopteris


  • Leaf of Caytonia with reticulate venation and palmate leaf shape
• Dinosaurs


  Coevolved with plants
• Sauropods


  • Mid Jurassic, Yorkshire reconstruction
• Stegosaurs


  • Late Jurassic
• Ornithopod grazers


  • Early Cretaceous, e.g. Iguanodon
• Hadrosaurs


  • Late Cretaceous
• High gas production in dinosaurs = high nutritional content
• Plants


  Coevolved with insects
• Sporivory


  Feeding on spores
• Pollinivory


  Feeding on pollen
• Insect pollination


  Complex plant-pollinator interactions already set up
• Bennettites


  • Pollinated by lacewings and beetles