Life during the Precambrian and Paleozoic Period. Learn what life was during these periods. Time during the dinosaurs. The time during the ice age. The age of mammals, reptiles, fishes, and dinosaurs. The first seed plant, the first flowering plant, the first primitives, the first appearance of fish.

1. General Biology [1/2]
Science, Technology, Engineering, and Mathematics
General Biology 2
Science, Technology, Engineering, and Mathematics
Lesson 3.2
Life during Precambrian
and Paleozoic Period

2. 2
Do you have any idea
how Earth looked like in
early times?

3. 3
Based on movies, it is depicted to have
unfavorable atmospheric conditions and a lot of
active volcanoes that erupt from time to time
which maintained a constant lava flow on Earth’s
surface.

4. Learning Competency
At the end of the lesson, you should be able to do the following:
4
● Describe general features of the history of life on
Earth, including generally accepted dates and
sequence of the geologic time scale and
characteristics of major groups of organisms
present during these time periods
(STEM_BIO11/12-IIIc-g-8).

5. Learning Objectives
At the end of the lesson, you should be able to do the following:
5
● Describe Earth’s conditions during the Precambrian
and Paleozoic eras.
● Enumerate possible life forms present during the
Precambrian and Paleozoic eras.

6. 6
Precambrian Era
● The Precambrian Era is a
predated era prior to the
emergence of life during the
Cambrian Period.
Earth’s Condition During Precambrian Era
Geologic time scale during the
Precambrian era

7. Divisions of the Precambrian Era
7
Precambrian Era
Hadean
Archaean Proterozoic

8. 8
Earth’s Condition During Precambrian Era
Period Events
Hadean
Earth’s surface was in the form of liquid rock
and boiling sulfur that built an ocean of hot
materials.

9. 9
Earth’s Condition During Precambrian Era
Period Events
Archaean
Earth’s interior was still hot and active and this
caused a series of volcanic eruptions. This
formed long chains of small islands. The
continents have not formed yet during this
time.

10. 10
Earth’s Condition During Precambrian Era
Period Events
Proterozoic
Earth was suspected to have two
supercontinents: one was located in the
equator and the other one was situated on the
other side.

11. 11
Paleozoic Era
● The Paleozoic era spanned
around 300 million years,
which was almost half of the
entire Phanerozoic. During
this time, there were six
major continental
landmasses.
Earth’s Condition During Paleozoic Era
The estimated location of the
supercontinents during the
Proterozoic era

12. 12
Paleozoic Era
● At the start of this era, the
world-continent Pannotia was
broken into pieces leading to
the formation of Pangea that
makes Earth's continents
connected once again.
Earth’s Condition During Paleozoic Era
The estimated location of the
supercontinents during the
Proterozoic era

13. 13
Paleozoic Era
● This era is mainly characterized by the explosion of
different life forms that started to emerge on Earth.
Earth’s Condition During Paleozoic Era

14. 14
Paleozoic Era
● The Paleozoic is divided into six periods: the Cambrian,
Ordovician, Silurian, Devonian, Carboniferous, and
Permian.
● These names were derived from original locations where
fossilized rocks of these ages were found.
Earth’s Condition During Paleozoic Era

15. Divisions of the Paleozoic
15
Paleozoic Era
Ordovician
Devonian Permian
Carboniferous
Cambrian Silurian

16. 16
Earth’s Condition During Paleozoic Era
Period Events
Devonian It is also known as the Age of Fishes.
Carboniferous
First seed plants and first reptiles
appeared.
Permian
It is marked by the extinction of 90% of
Earth’s species.

17. 17
Precambrian Era
● Ediacarans appeared in
the fossil record that was
dated almost 600 million
years ago.
Life Forms During Precambrian and Paleozoic
Eras
Different species of Dickinsonia
dated during the Precambrian Era

18. 18
Precambrian Era
● One of the important
Ediacarans was the
Dickinsonia, which
resembles a ribbed doormat.
Life Forms During Precambrian and Paleozoic
Eras
Different species of Dickinsonia
dated during the Precambrian Era

19. 19
Paleozoic Era
● Vertebrates first appeared
525 million years ago
during the Cambrian
explosion.
Life Forms During Precambrian and Paleozoic
Eras
The Cambrian explosion

20. 20
Paleozoic Era
● Trilobites were the dominant
species during the Cambrian
period.
● These organisms are extinct
groups of arthropods.
Life Forms During Precambrian and Paleozoic
Eras
Trilobite fossils

21. 21
Paleozoic Era
● The Silurian to the
Permian period was
dominated by crinoids,
echinoderms,
brachiopods,
graptolites, and rugose
corals.
Life Forms During Precambrian and Paleozoic
Eras
A fossilized crinoid

22. 22
Paleozoic Era
● Eventually, the primitive
tetrapods emerged.
Life Forms During Precambrian and Paleozoic
Eras
Acanthostega

23. Let’s Sum It Up!
23
● The Precambrian Era has three major subdivisions:
Hadean, Archean, and Proterozoic. Today, it is
known that life on Earth started during the early
Archean, thus making fossilized organisms increase
throughout the Precambrian time period.

24. Let’s Sum It Up!
24
● The Paleozoic is divided into six periods: the
Cambrian, Ordovician, Silurian, Devonian,
Carboniferous, and Permian. These names were
derived from original locations where fossilized rocks
of these ages were found.

25. Let’s Sum It Up!
25
● During this period, single-cell and multicellular
organisms started to emerge. The first multicellular
animals, also known as Ediacarans, appeared in
the fossil record that was dated almost 600 million
years ago.

26. Let’s Sum It Up!
26
● The most advanced form of animals such as the
vertebrates or animals with backbones first
appeared 525 million years ago during the
Cambrian explosion.

27. Let’s Sum It Up!
27
● Most phyla of the modern times were present during
the Cambrian but trilobites, brachiopods,
mollusks, hyolithids, and archaeocyathids were
the most abundant.

28. Let’s Sum It Up!
28
The Cambrian explosion led to the emergence of
various phyla of organisms.