What are eons?
The longest units of geologic time
What is a mass extinction?
This is the extinction of many species within a short period of time.
What are invertebrates?
These animals do not have backbones.
These reptiles dominated life among land vertebrates during the Mesozoic Era.
dinosaurs
What is the Cenozoic Era?
This is the era in which we live today.
Name the four units of the geologic time scale from largest to smallest.
eons, eras, periods, and epochs
Gas and dust released by this natural events can block sunlight and lower temperatures.
volcanic eruptions
What are vertebrates?
These animals have backbones.
What was a warmer climate the Mesozoic Era or the Paleozoic era ?
Mesozoic Era
What is the Holocene Epoch?
This is the most recent epoch.
What era is the oldest era of the Phanerozoic Eon.
Paleozoic Era
This element found in clay and rocks around the world provided evidence of a meteorite impact.
iridium
Many types of these aquatic vertebrates lived during the Paleozoic Era
Fish
what are the three periods of the Mesozoic Era.
Triassic, Jurassic, and Cretaceous
What is the Pleistocene Epoch?
This was the first epoch of the Quaternary Period.
What era is the youngest era of the Phanerozoic Eon and continues today?
Cenozoic Era
This happens to a species when it cannot adapt to changes in its environment.
extinction
What was Tiktaalik
. An organism that had lungs and could breathe air
When Pangea broke apart, these two major landmasses formed.
Gondwanaland and Laurasia
This era is called the Age of Mammals because these animals became very successful.
mammals
Scientists study these two types of evidence preserved in Earth's layers to learn about the past.
rock layers and fossils
Scientists hypothesize that these two events contributed to the mass extinction associated with the end of the age of dinosaurs.
volcanism and a meteorite impact
These oxygen-poor environments contained dense tropical forests and helped form coal deposits.
coal swamps
This era lasted from 252 million years ago until 66 million years ago.
Mesozoic Era
What is an Ice Age?
This is a period when a large proportion of Earth's surface is covered by glaciers.