The Permian Period

1
The Permian Period

• Began 286 million years agoEnded 245 million
  years ago
• Lasted 041 million years

2
Permian Period

• The Permian Period was named after the
• former U.S.S.R. province of Perm. This is
• where the rock samples dated to this period
• were first found.

3
Defining Factors

• This period marked the greatest extinction in the
  history of the earth.
• This extinction was most likely caused by the
  combination of overspecialized organisms and
  climate change.

4
Extinction

• 75 of the amphibian families and 80 of the
  reptilian families became extinct during this
  period.
• Eurpterids, trilobites, blastoids, and rugrose
  coral also became extinct during this time
  period.

5
Geography

• Most of the surface area of
• the Earth was occupied by a
• corresponding single ocean,
• known as Panthalassa, with a
• smaller sea to the east of
• Pangea known as Tethys.

6
Biology

• The cooler climate allowed conifer trees to
  become the dominate woody plant
• The insect population expanded in variety and
  numbers, but their overall size decreased. The
  amphibians continued to increase in variety, but
  their size too remained small.
• The great forests of fern-like plants shifted to
  gymnosperms. Modern conifers, the most familiar
  gymnosperms of today, first appear in the fossil
  record of the Permian Period.

7
Climate

• The climate became colder during this period
  which is partially responsible for the mass
  extinction. The climate also allowed for the
  conifers to dominate.

8
Triassic Period

• Began 245.0 million years agoEnded 208.0
  million years agoLasted 037.0 million years

9
Triassic Period

• The Triassic period was named for the
• three level structure of the rocks. It was
• therefore given the prefix trias-.

10
Defining factors

• The Triassic period was a time of transition and
  development. Most of the previously dominant
  species were extinct.
• This period built the foundations for the entire
  Mesozoic era

11
Geography
12
Geography

• Wyoming, Alaska and British
• Columbia were slowly
• submerged as well.
• The area between British Columbia and Alaska
  suffered much volcanic activity.
• Rain was inconstant throughout the period and
  produced varying regional climates.

• The continents were in one large section with the
  exception of Europe, Siberia and China
• The Appalachian, Andes, Palisades, Caucasus and
  Urul Mts. Progressed in their formation.
• California and Nevada were submerged. Idaho,
  Colorado,

13
Biology

• From a historic perspective the organisms can be
  divided into 3 groups
• Those that were holding on after the great
  extinction.
• Those that were briefly dominant but faded
  away.(Ammonites)
• Those that went on to dominate the Mesozoic era.

• Plants Marine algae and fruit trees become
  abundant.
• Animals Many invertebrates (especially bugs.)
  Many fish developed(holosteans and coelacanth.)
  First mammals appear. Modern corals and
  insects appear.

14
Climate

• The climate of the Triassic Period was semiarid.
  
• During this period, with the remains of many
  species, coal began to form.