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Notes on video lecture:
Determining Dinosaur Appearance
Choose from these words to fill the blanks below:
Wyoming, Tyrannosaurus, decomposes, calcium, black, plates, Theropods, velociraptor, sediment, chemistry, corona, ancestors, scales, feet, melanosomes, Ankylosaurus, gila, bacteria, mud, quickly, dermis, scaly, brown, skin, toes, spikes, slowly, eumelanosomes, seldom, soft, fleshed, adaptations, turtle, skin, green, fingernails, integumentary, pigment, Cretaceous, bristles, mummified, appearance, volcanic
museums often display fully               -out models of dinosaurs
paleontologists have some methods to determine the                      of some dinosaurs based on dry bone fossils
bones are hard, mineralized structures that rot away             
muscles, organs and skin decay               
they are              fossilized
however, sometimes paleontologists get a rare glimpse of a dinosaur's          anatomy
footprint are natural molds of dinosaur         
usually are no more than the sloppy outline of a dinosaur's         
sometimes the tracks are so well preserved that they include impressions of the              from the sole of a dinosaur's foot
in very rare cases dinosaurs were buried by        soon after death
skin impressions formed in the mud before the flesh had time to rot away
sometimes true fossils of the         , not just molds, can form
these are referred to as                   
large regions of the skin hanging off the bones
              , 1910
Hadrosaurs
claws, beaks, hairs and feathers are composed of keratin
harder than flesh and                      faster than bone
rarely fossilizing
                           structures, i.e. the organ system that protects the body from damage
Psittacosaurus
fossilized remains of tall                  along of tails
unclear what the bristles were for
many dinosaur bones were discovered with fossilized feathers
                         has feathers
many dinosaur groups, not just birds, had feathers
bird fossils from early                      Period in China
claws of hand on wing
discoloration of the claw, where fingernail was
shows feathers around body
lake bed deposits
                 ash mixing in with silt
like mud it preserves detail
also alters the                    of the water
so where features such as feathers and                        would normally be destroyed by decomposition by bacteria, this                  can't live in water heavily altered by volcanic ash
as long as feathers are sandwiched between two layers of                 
the feathers preserve as a              or halo around the outside of the body
based on fossil record, the following dinosaurs should probably be displayed with feathers
definitely velociraptor since some skeletons have been found with fossilized feathers
Tyrannosaurus should probably be as well
we have no evidence that                            had feathers
we have evidence that some                    of Tyranosaurus had feathers
therefore it's likely that the Tyrannosaurus kept these integumentary                       
many dinosaur fossils preserve            skin impressions
there are many Hadrosaur fossils with skin impressions
there are fossil from Stegasaurus which had scaly skin as well
the skins of                          and Stegosaurus
both have bones called osteoderms
skin bones
bones formed completely within the             , the lower layer of skin
some modern animals have osteoderms
armadillos
crocodiles
some lizards such as the          monster
             shells are not osteoderms, as they form through a different process
osteoderms are what give Ankylosaurs and Stegosaurus their spiky appearance
Ankylosaurus
form the knob of bone on the tail
small and large             
Stegasaurus
form the giant              on back and spikes on tail
growing these extra exterior bones uses up a great deal of energy but they are very useful
storing               
gathering heat from the sun
protection from biting and clawing predators
attract mates and intimidate rivals
feather colors
feather colors are not preserved in feather colors
in modern birds, feather color is caused by the shape and arrangement of                cells called eumelanosomes
long and narrow correspond to black and gray
short and wide correspond to brown and reddish           
white feathers had no                           
narrow aligned in the same direction lead to glossiness
some colors of some                    have been able to better determined by studying evidence of their eumelanosomes
the Dromaeosaur Microraptor was probably glossy black
the Archaeopteryx had at least some            feathers
we don't yet know of any fossil feathers that were blue,           , or red
Sinosauropteryx colors
we can study preserved                        to better determine colors
red-brown with stripes most probable
skin colors
there is still no evidence regarding the color of dinosaur         
How are Dinosaurs Different than Other Animals?
Dinosaur Skeletons
Saurischians: Sauropods, Theropods, and Prosauropods
Ornithischians
Determining Dinosaur Appearance