1-Why is the Cambrian explosion an important biologic event in Earth’s history?
The Cambrian explosion marks the first appearance of stromatolites.
The Cambrian explosion was the meteor impact that killed the dinosaurs.
The Cambrian explosion marks the first time that organisms developed hard parts.
The Cambrian explosion marks the first evidence of life on Earth.
The Cambrian explosion describes the evolution of humans.
2- What was the Cambrian Explosion?
the introduction of vertebrate animals during the Cambrian period
the expansion of biodiversity that introduced all the major invertebrate groups during the Cambrian period
a mass extinction of many different types of organisms for reasons unknown
the remarkable increase in populations of organisms that already existed before the Cambrian period
a period of heavy volcanism during the Cambrian period that wiped out half of the types of organisms that currently existed
3- Gymnosperms were the dominant ________ of the Mesozoic.
4- What group of reptiles led to the evolution of birds?
5- Following the reptilian extinctions at the close of the Mesozoic, two groups of mammals, the marsupials and ________, diversified.
6- _______ (flowering plants) came to dominate most terrestrial environments during the Cenozoic.
7-Most of the evidence related to human evolution has been found in ________.
Northern North America