Palaeontology and Evolution Flashcards
What is palaeontology?
The study of fossils
What are the 5 time scales from largest to smallest?
Eon, Era, Period, Epoch, Age
What are the 4 eons?
Hadean, Archaean, Proterozoic, Phanerozoic
What are the 3 eras in the Phanerozoic eon?
Paleozoic, Mesozoic, Cenozoic
What are the 6 periods in the Paleozoic era?
Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian
What are the 3 periods in the Mesozoic era?
Triassic, Jurassic, Cretaceous
What are the 3 periods in the Cenozoic era?
Paleogene, Neogene, Quaternary
What are the 3 epochs in the Paleogene period?
Paleocene, Eocene, Oligocene
What are the 2 epochs in the Neogene period?
Miocene and Pliocene
What are the 3 epochs in the Quaternary period?
Pleistocene, Holocene, Anthropocene
What events typically mark the end of an era?
Mass extinctions
How does radiometric dating determine absolute ages?
By measuring the radioactive decay of certain isotopes
How did we determine the age of the earth and the solar system?
Using radiometric dating to calculate the age of meteorites as being 4.5 billion years old, and earth and the rest of the solar system would be about the same age
Where are the oldest rocks on earth?
Northern Quebec, 4.4 billion years old
Where are the oldest known fossils on earth?
Shark Bay, Australia, stromatolites that are 3.5 to 3.8 billion years old
Why there is there a geographic bias in the fossil record?
Marine environments have much higher representation because of better fossilization conditions
Why is there a taxonomic bias in the fossil record?
Most fossils are marine species with shells, and most known species are not marine species with shells
Why is there a temporal bias in the fossil record?
Older rocks are much rarer than newer rocks
What are plate tectonics?
The earth’s crust is divided into plates that float on semi-liquid magma
What were the changes in foraminiferan tests observed by Kucera and Malmgren?
The tests became increasingly cone shaped over a period of 3 million years, showed anagenesis after a 2.5 million year stasis period
What were the changes in trilobites observed by Sheldon?
Various species in different genera were changing gradually in the same feature - number of ribs on the rear dorsal exoskeleton over 3 million years
What were the changes observed in sticklebacks by Bell?
Morphology changes that showed gradual changes in multiple directions
What were the changes observed in suckers by Wilson and Barton?
Gradual drop in vertebrae number over 600 years, and a gradual change in fin ray number over 8000 years
