Exam 3 Flashcards
Dryptosaurus, discovered in Mantua Township NJ in 1866, was the first known member of which theropod clade?
Tyrannosauroidea
[T/F] a group of theropods is still alive today
true
What is a probable function of the extremely long, thin claws on the hands of therizinosaurian theropods?
They used them to grab onto branches/food
it suggests that dinosaurs may have died due to blindness caused by cataracts or the explosion of a nearby star in a supernova event. Why are these ideas not viable scientific hypotheses?
It would suggest that it affected every living dinosaur and not the other mammals living during that time which caused only the dinosaurs to die of blindness and no other mammals. It also is not testable or parsimonious.
A spike in enrichment of the element iridium has been found in the K/Pg boundary layer around the globe. How is this iridium important toward resolving what caused the extinction of non-avian dinosaurs?
This accumulation in the layer of rock indicates dust from an extraterrestrial source, an asteroid.
[T/F] extinction can only be caused by a rapid, catastrophic event
false
What defines a feather as a “flight feather”?
it is strong due to interlocking barbules within its structure
[T/F] Most dinosaur skeletons mounted in museums are complete skeletons of single individuals.
false
How are most feathers preserved in the fossil record?
as flat, carbonized films
[T/F] Several dozen news stories are published every day about dinosaurs.
true
Scientific evidence supports which of these behaviors in some dinosaurs?
burrowing, flight, cannibalism, migration
What percentage of species are extinct?
99.9%
Extinction of the dinosaurs Categories Medical problems example?
- disease, parasite epidemic, blindness, senility
(scientific thinking…) - is it testable? is it parsimonious
Extinction of the dinosaurs Categories Caused by other lifeforms (mammals or plants) example?
- starvation, deforesation, outcompeted by mammals
Extinction of the dinosaurs Categories atmospheric changes example?
extreme climate change / fluctuations. wildfires, high C02
Extinction of the dinosaurs Categories geological causes example?
global cooling
Extinction of the dinosaurs Categories extraterrestrial causes example?
sunspots, comet/ asteroid impact, cosmic radiation
Extinction of the dinosaurs Categories Caused by other lifeforms (mammals or plants) example?
- starvation, deforestation, outcompeted by mammals
Extinction of the dinosaurs Categories Caused by other lifeforms (mammals or plants) example?
- starvation, deforestation, outcompeted by mammals