Death and Fossilization Flashcards
What is taphonomy?
study of natural processes that involve an organism after it dies (including decay, scavenging, fossil, erosion)
TRUE or FALSE: dinosaur carcasses are found in the same location where they died.
FALSE –> they move via scavengers/predators carrying their carcasses and “bloat-and-float”
What is the bloat-and-float phenomenon?
after death, body swells with putrid gasses –> float –> transported by flowing water
Name some factors that causes disarticulation of a skeleton (aka incomplete dinosaur skeleton).
- partial consumption by carnivores
- rotting can make the body easier to damage
- water currents carry away body parts
- prolonged exposure to sunlight weakens/disintegrates bones
- partially buried skeletons may lose unburied portions
- trampling
- plant roots leach away mineral content of bones
What is plastic deformation?
occurs when pressure causes shape of a buried fossil to change even after the pressure is removed (i.e. does not return to original shape)
How does burial of a dinosaur carcass often occur?
water washes sand or mud over the carcass
Fossilization is more common at:
a) low elevations
b) high elevation
Explain your choice.
a) low elevations
Low elevations promote fossilization because sand and mud carried by water can permanently build up (whereas, sand and mud are eroded at high elevations before they can permanently build up).
What are fluvial deposits?
river and stream deposits
What are lacustrine deposits?
deposits (animals that died) preserved in lakes
Which type of deposits have a better chance of preserving soft tissues like hair or feathers?
a) lacustrine deposits
b) fluvial deposits
c) aeolian deposits
Explain your choice.
a) lacustrine deposits
- little water movement –> less disruption to skeleton
- mud/fine sediment better for preserving feather impressions than sand/large sediment
Even though there were no marine dinosaurs, we sometimes find dinosaurs in ancient _____________ environments, if the dinosaur was washed out to sea during a storm or tsunami. (Fill in the blank.)
coastal
TRUE or FALSE: many dinosaurs can be found in deeper-water environments.
FALSE: this is very rare (mostly found in coastal environments)
Dinosaurs in the deserts of Mongolia could be buried by _______ ________ that collapsed onto the still living animal. (Fill in the blank.)
sand dunes
Why are the dinosaurs of Mongolia often preserved in crouching positions with their necks reaching up towards the air?
when dunes become wet and saturated, during heavy rainstorm, the dunes collapsed onto the dinosaurs
What kind of rock/stone are dinosaurs in Alberta often found in?
sandstone
