Things I learned while reading “Dinosaur Heresies,” by Dr. Robert T. Bakker:  pp. 105-198. Part 2

On page 107, Dr. Bakker talks about tiny limestone balls called ooids (“oh-oyds”).  I then looked up the word oocyte (with the same prefix), which is the term for an unfertilized egg and discovered it is pronounced similarly (“oh-oh-cyte”).  I have been pronouncing oocyte “oo-oh-cyte” my whole life while teaching biology and Anatomy and Physiology.  Oops, looks like I needed some Bakker to cure my hillbilly pronunciation.

On page 110, Bakker reveals that dinosaurs had constantly replaced teeth.  On an unrelated side-note:  I have pondered this idea as I have searched for fossil shark teeth at Frankstown, MS at the W.M. Browning Cretaceous fossil park.  Sharks are not reptilian as dinosaurs, but also have constantly replaced teeth.  Apparently, a shark can shed thousands of teeth in its lifetime.  This seems to explain the ubiquitous nature of fossil shark teeth in and around the Cretaceous layers uncovered near Baldwyn, MS.

I learned on page 113 that “taphonomy” is the process of noting the circumstances of a burial to learn about the life of the organism.  Bakker used the idea to discuss the misconception of determining that animals whose fossils are found in river sediment were habitants of the river.  He made the case that animal burial in lakes typically preserved water creatures and flood plains preserved land creatures.

I did not know that dinosaurs had gizzards with rocks inside that literally helped them grind their food (Bakker 127).  It is interesting how that geologists and paleontologists have been confused by random piles of pebbles in New Zealand (Bakker 136); It is now thought that these represent “dinobelches” of gizzard stones.  The idea is that as gizzard stones wear down, they become less effective and so the dinosaur would basically regurgitate them and find more.  Gizzard stones were discussed by Bakker because the effectiveness of the gizzard in digesting vegetable matter would be important to support high metabolic rates in dinosaurs with long necks and tiny heads such as the brachiosaurs.

I learned on page 141, that some think the long-neck Diplodocus may have had an elephant-trunk due to the anatomical placement of its breathing hole on top of the head.  Hmmmm..

“Paleopodiatry” is the study of dinosaur feet.  In the section on page 157, it was showcased to determine the suitability for duckbills and brontosaurs walking about in swamps.  Bakker suggested that it was not likely that these critters lived in aquatic environments based on their small foot size:  they would get stuck too easily.

I learned on page 165 that modern reptiles have no cheeks.  Interesting.  It was the same with meat-eating dinosaurs.

On page 169, Dr. Bakker elucidated that the large frill of the triceratops was helpful to provide muscle attachments for chewing.

Unlike humans, dinosaurs had ribs attached to all vertebrae from the thoracic to the pelvic region (Bakker 173).

On page 195, Bakker suggested that angiosperms (flowering plants) proliferated as a result of aggressive grazing by these dinosaurs:  duckbills, ankylosaurs and anchiceratops.   Angiosperms are faster-growing and can respond more quickly to overgrazing than conifers or cycads.  He thus attributed dinosaurs as a possible direct cause of angiosperm proliferation and dominance.

I believe having the privilege of reading and digesting Dr. Bakker’s book is like taking an upper level college or graduate level paleontology course.  Due to his understanding of kinesiology (how animals move), he gives great insights to the habitus of the dinosaur.  Due to his grasp of ecology and physiology, he also does an intuitive job integrating the dinosaur into the landscape of its time.  I hope to use some of these “nuggets of gold” in my freshman and sophomore biology classes as I teach my students.

Citation

Bakker, Robert T. The Dinosaur Heresies.  William Morrow and Company, Inc., 1986.