Mary Anning: Plesiosaurs, Pterosaurs and The Age Of Reptiles

What do you think of when someone mentions the Jurassic or Cretaceous ages? Most likely you will immediately think of dinosaurs and other large reptiles such as pterosaurs.  Maybe you think of the movie Jurassic Park and the dinosaurs and lush vegetation.   These periods are also known as the Age of the Reptiles and aptly so since many layers of the fossil record are loaded with animal bones that belong almost solely to reptiles of some variety.  In marine sediments hundreds of sea reptiles (ichthyosaurs and plesiosaurs) have been found around the world and in terrestrial rocks dinosaurs and pterosaurs (flying reptiles) are found to the near exclusion of any other vertebrates.

1800s lithograph (unknown source) of the flora of the Jurassic. Notice the lack of flowing plants. Most of these plant are extinct today.  Also not the lack of grass which is a flowing plant but did not exist in the Jurassic.

1800s lithograph (unknown source) of the flora of the Jurassic. Notice the lack of flowing plants. Most of these plant are extinct today. Also not the lack of grass which is a flowering plant but did not exist in the Jurassic.

In addition to their bones, fossils of plants found in the same layers of rock revealed strange coniferous (pine-like) trees along with many cycads and tree ferns but no flowering plant trees at all!  No oaks, maples, sycamores, etc..  have been found in these rocks. More significantly so far no flowering plant tree remains have been found in the fossilized feces (coprolites) of those massive plant-eating dinosaurs of the Jurassic (see article:  Dino Doo Doo (Coprolites) and the Genesis Flood).  Some small flowering plants may have lived at this time but they clearly did not make up any significant part of the flora.

Whether you imagine these scenes from a book or a movie, a significant source of our views of the Age of the Reptiles traces itself back to the early 1800s and a woman who from childhood was fascinated with fossils.  Mary Anning (1799-1846) by the age of 12 had already discovered in rocks of the English countryside fossils that she would later describe as a plesiosaur.  She spent more than 30 years collecting and describing fossils mostly in rock of Jurassic age.   Anning along with William Buckland, who was well aware and an admirer of Mary’s work and described the first true dinosaur, and Cuvier who described and wrote about dinosaurs were instrumental in developing a picture of life in the Jurassic.  It eventually lead to Cuvier’s specific proposal that there had been an “age of reptiles.”  This was a time when reptiles would have been the dominant animal in all places on earth versus the mammals that we have today.  Like the discovery of deep time itself over the previous century this idea of earth’s changing biota over time presented a serious challenge to established views of creation.

Mary Anning homage on Google today.  Image credit: Google Inc.

Google Inc paid homage to the 215 anniversary of the birth of Mary Anning on May 21 2014 with this Doodle on the homepage. Image credit: Google Inc.

Below is a watercolor painted in 1830 showing a scene from the Jurassic time period resulting from the fossils that Mary Anning had discovered and described.   This is an amazing scene considering that we have made so many new discoveries since that time and yet the basic reptiles shown here are the main ones we recognize today.

Duria Antiquior - A more Ancient Dorset is a watercolour painted in 1830 by the geologist Henry De la Beche based on fossils found by Mary Anning, and was the first pictorial representation of a scene from deep time based on fossil evidence.  Image: Wikipedia

Duria Antiquior – A more Ancient Dorset is a watercolour painted in 1830 by the geologist Henry De la Beche based on fossils found by Mary Anning, and was the first pictorial representation of a scene from deep time based on fossil evidence. Image: Wikipedia

In many ways Cuvier’s proposal based on the work of Anning and Buckland and others capped off a 100 years of work that had developed the idea of “deep time”  or the great age of the Earth.   The fossil record was now increasingly seen as showing that not only was the earth very old but the fossils recorded time since the distant past  show us life was very different from what we see today.  This idea of changes in earth’s biota over time was yet another significant challenge to scriptural (Mosaic) geologists of the day and set the stage for even bigger challenges to follow.

It was this recognition of the great changes of life from past to present hat paved the way for Darwin and others to explore how those changes might have occurred.   Before Darwin it wasn’t hard to see that organisms had changed or at least been replaced with different organisms throughout the history of the earth but what was the mechanism for that change?  Darwin provided a possible mechanism with his theory of “natural selection.”   Darwin is often given credit coming up with the idea of evolution but  the idea that organisms were different in the past than the present was not novel to Darwin. Rather Darwin was responding to what had already become a well established idea in his time.

About these ads

Comments

  1. You have a lot of nice articles here. I wish I had your productivity. I do have one question though. You state that no dinosaur coprolite has the remains of angiosperms. Are you specifically referring only to the Jurassic? Although i grant there is no evidence in the Jurassic, there have indeed been dinosaur coprolites containing angiosperms from the Cretaceous. We even have grass in coprolites from the Maastrichtian. While it is true that angiosperms did not seem to radiate and become abundant until the mid-Cretaceous, there is well-documented evidence since the beginning of the Cretaceous and possibly as far back as the Triassic if the fossils reported by Hochuli and Feist-Burkhardt last October are true. Thus, it would seem unlikely that dinosaurs waited until the very end of the Cretaceous to eat them, especially considering the prodigious dental batteries seen in the hadrosaurs. There is also the small problem of taphonomic bias in that herbivore feces does not preserve as well as carnivore feces due to the rich nutrient source in the carnivore feces feeding the bacteria which mineralize the feces, making herbivore coprolites rarer and ranges thus more uncertain.

    • Thank you so much for the clarification. Yes, I definitely meant in the Jurassic and have made that change. I did talk about trees on purpose because I knew it was possible were a few small angiosperms in the Jurassic. I haven’t kept up on the last couple years of angiosperm palaeobotanical developments (embarrassing since I have published in the past on land plant evolution). I knew that angiosperms have been pushed back to the early Jurassic but most modern groups of any significance had evolved before the Cretaceous. I really appreciated the time you have taken to set me straight here and will be more careful in the future. Joel

  2. Daren H says:

    A correction? Please change “flowing plant” to “flowering plant” underneath the first picture.

  3. I tried to comment earlier but it didn’t go through.Anyway:

    Thanks for this post, I really enjoyed it. I think it’s very important to have this kind of historical background in mind when dealing with any kind of young earth believers, because so often I encounter the notion of “evolutionary” time sales and the like, when of course that very notion is an anachronism. Thanks for this important post, and more like it! I’ll be sharing it next week on my “Really Recommended Posts.”

Trackbacks

  1. […] Mary Anning, Plesiosaurs, Pterosaurs, and the Age of Reptiles- Google recently had a celebration of Mary Anning on the search page. What’s the big deal? Here, Joel Duff explores some of the implications of Mary Anning’s discoveries about the “Age of Reptiles.” Want to read more on big lizards and time scales? Check out my post about dinosaurs, Noah’s Flood, and creationism. […]

Please leave a response. I will reply as soon as I am able.

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 376 other followers

%d bloggers like this: