the remains of a species that existed over vast regions of Earth for a short period of time.
What are INDEX fossils?
100
the dying off of many different species of organisms over a short period in geologic time.
What is a mass EXTINCTION?
100
single-celled, blue-green algae thought to be one of the earliest known, ancient organisms.
What are CYANOBACTERIA (Blue-green algae)?
100
animals with backbones
What are VERTEBRATES?
100
Organisms need to be buried quickly after death to avoid this, the breakdown of an organism.
What is DECAY?
200
the largest divisions of time with the longest units of time on the Geologic Time Scale
What are EONS?
200
an event that causes a drastic change in the numbers of organisms of one or more species over a short period in geologic time.
What is a CATASTROPHIC event?
200
Even though not many thing existed during this era, most of the time in the geologic time scale happened during this era.
What is PRECAMBRIAN?
200
These animals, like jellies, sponges and corals also evolved during the Cambrian explosion.
What are INVERTEBRATES?
200
Footprints are a type of this fossil.
What are TRACE fossils?
300
Eons are divided into smaller units called this.
What are ERAS?
300
Evidence that some mass extinctions were caused by sudden changes in this.
What is CLIMATE?
Species that are unable to survive a change in climate become extinct.
300
The absence of oxygen during the Precambrian time suggests there was no this. (This allowed us to survive because it regulated temperature!)
What is OZONE LAYER?
300
Another common fossil which looked like a tiny coiled snail.
What is an AMMONITE?
300
Fossils preserved in tar, ice, amber, or volcanic ash, are these type of fossils.
What are ORIGINAL REMAINS?
400
Eras are broken into ___________ and sometimes, epochs.
What are PERIODS?
400
Possible catastrophic events include volcanoes, climate change, and this which is proposed to be the reason why the dinosaurs are now extinct.
What is ASTEROID/METEOR IMPACT?
400
Most of the life during the Cambrian explosion lived in the ____ as evidence shows that many animals had shells.
What is OCEAN?
400
Life on Earth exists because plants like algae made oxygen through this process.
What is PHOTOSYNTHESIS?
400
Plate tectonics affects evolution because movement of the plates cause a change in this.
What is the ENVIRONMENT?
500
The most recent era (the one we are currently in!)
What is CENOZOIC?
500
Evidence shows that large basalt flows occurred
A. during the Jurassic Period in India.
B. during the Cambrian Period in Hawaii
C. during the Permian Period in Siberia.
D. None of the above.
What is C. during the Permian Period in Siberia.
500
These animals with hard outer skeletons were the most commonly fossilized organisms of the Cambrian period and are the ideal index fossil. Also... Mrs. Green's favorite fossil!
What are TRILOBITES?
500
Dinosaurs did NOT live at the same time as humans. Dinosaurs lived during this era.
What is MESOZOIC?
500
Fossils can be carbon dated, which provides its actual age, or it's this.