UPDATES
Marine Reptiles
Turtles
The assessment of turtles has been radically changed by the realization that they are diapsids: that the lack of a skull opening (their anapsid state) is a secondary modification of what was once a diapsid state. They are certainly early diapsids, but it is not yet clear where they belong within that major group. As you would expect, the extent to which they are modified for aquatic life means that they may not retain important features that their undoubted terrestrial ancestors had. Stay tuned. Reference: Rieppel, O. 1999. Turtle origins. Science 283: 945-946. Here is the paper. For a lecture that includes this stuff, from an expert, see this Web page.
Crocodiles
Protorosaurs
The long-necked protorosaur Dinocephalosaurus: update from 2004.
Placodonts
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Placodont page at the Oceans of Kansas Web site. Text by Darren Naish, with loads of information. Updated 2004.
Ichthyosaurs
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Ryosuke Motani published a review of ichthyosaur biology in the December 2000 issue of Scientific American. It's reposted here.
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Feature article on ichthyosaur biology. by Sid Perkins in Science News, August 24, 2002. This is clearly a superior article because it refers to my speculations on ichthyosaur swimming. But there's lots more than that...
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Introduction to ichthyosaurs
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Some Triassic ichthyosaurs were gigantic
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Image of Ichthyosaur with skin
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Some beautifully preserved ichthyosaurs were collected on a 1905 Expedition to the West Humboldt Range in Nevada
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Many ichthyosaurs had huge eyeballs, consistent with deep diving. Story from BBC News OnLine, Thursday, 16 December 1999.
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Ichthyosaur vomit? National Geographic News, February 12, 2002. The evidence is a bit circumstantial, but on the whole plausible.
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Gut contents of a Cretaceous ichthyosaur. National Geographic News, August 5, 2003. These included fishes, hatchling turtles, and a bird. I would guess the ichthyosaur was trolling just off the beach, waiting for its annual feast of baby turtles (and the fish and the bird were doing the same thing). Now I should go and read the paper when it's published and see what kind of sedimentary environment it's preserved in. Should be shallow water!!
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Painting of ichthyosaurs.
Sauropterygians
Mosasaurs
Air Breathers at Sea
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My online article on How marine reptiles breathed.. The logical structure of the argument is still sound. However, ichthyosaurs solved Carrier's Constraint in a way that I had not thought of. Ryosuke Motani told me that ichthyosaurs have very large flat centers to their vertebrae, which indicates a big flat plate of cartilage between them. This system would not have allowed the ichthyosaur spine to flex, making it relatively rigid and thus solving Carrier's Constraint. So my inferences about ichthyosaurs having to leap like penguins do not hold. Ichthyosaurs could have done, but that's speculation, not inference.
Mesozoic Floras
Why Flowers Are Beautiful
The Earliest Angiosperms
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The earliest flower, Archaeanthus. A paper in Science in May 2002 gives more details about Archaeanthus, the earliest known angiosperm from the Liaoning beds of China.
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Story from the New York Times on an astounding collection of charcoaled angiosperms, including their flowers, from a site in New Jersey, dating from 90 Ma. Obviously there is an enormous amount of paleobotany that will come out in the next few years; possibly it will revise many of our current ideas. December 21, 1999.
The Most Primitive Living Angiosperm
is NOT, of course, the same thing as the earliest angiosperm. The most primitive living angiosperms are a bush from New Caledonia called Amborella, and the water lily, Nymphaea. These two plants are very different, which means they don't help in any definitive way in reconstructing what the earliest angiosperm was like, over 100 m.y.ago! But see the update on early angiosperm ecology from Feild et al. 2004.
Plants and Pollination
This takes you to a subsection of another page with Web links: you can return here when you finish the section on this topic, by using the "Back" button.
Gymnosperms and Early Angiosperms, and their Early Pollinators
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Jurassic Park plants from Wayne's Word at Palomar College.
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See also this page from Wayne's Word
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Cycads and their pollinators. August 1998.
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Pollinating cycads with a turkey baster.BBC News OnLine, September 9, 2003. I went on and on in the book about the ways in which plants can persuade pollinators to help them reproduce. But this is a new twist. My respect for cycads deepens.
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Images of Cycads
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The astonishing Welwitschia, now thought to be a relative of gymnosperms rather than angiosperms. Feature article from California Wild, the magazine of the California Academy of Sciences in Golden Gate Park, San Francisco, Winter 2000.
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The Wollemi pine of Australia, thought to have been extinct for over 100 million years. It is an araucarian tree, over 100 feet high, surviving in wild country only 100 miles or so from Australia's largest city, Sydney. Here is a recent story: From the brink of extinction to your flower pot: the Wollemi pine of Australia.BBC News OnLine, September 25, 2003. Here is an earlier story, also from National Geographic News, March 2003.
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By the Early Cretaceous there were representatives of Winteraceae
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More examples of Winteraceae
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A newly discovered "living fossil" winteracean plant from Madagascar
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Another news story about this.
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Images of the relatives of Winteraceae, the magnolias
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Ancient beetles chewed early flowering plants. RC: get the link to this paper: Science, July 14, 2000. We do not know these beetles as Cretaceous fossils, and we don't know whether they acted as pollinators. But we can see their characteristic activity preserved as damage on fossil leaves. Great detective work!
Some Insect Pollinators
Pollen Robbers
Plants and Seed Dispersal
Seed dispersal by non-biological agents
Seed dispersal by biological agents
Angiosperm Ecology and Evolution
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A Huge Phylogeny of Angiosperms Based on DNA Sequences: Treezilla
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The earliest ants, around 92 Ma. From the Washington Post, January 1998.
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Ants and acacias. Another great story of co-evolution between plants and animals. This time it's a protection racket.
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Ants that grow gardens of fungus
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I am very sorry to report that the Japanese are in the process of killing off the largest supercolony of ants in the world, near Sapporo, Japan.
Angiosperm Chemistry
The reference list for Chapter 14, 4th Edition, with associated Web links
Page last updated October 13, 2005.
Links last checked, October 3, 2005.
[For Chapter 13, click here ]
[For Chapter 15, click here ]
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