Geological Periodization of Prehistoric Times (Praaksara)
🗿 Prehistoric times (Praaksara) are categorized based on geology (rock age) into four major eras: Archaeozoic, Paleozoic, Mesozoic, and Neozoic.
🌋 The Archaeozoic (Archean) era, starting around 2.5 billion years ago, was characterized by unstable earth surfaces, active volcanoes, and very hot temperatures, allowing only simple organisms like cyanobacteria to survive.
🌊 The Paleozoic era, beginning about 600 million years ago (meaning "ancient life"), saw the formation of the hydrosphere and atmosphere, marked by the Cambrian explosion of diverse life forms, primarily aquatic.

Paleozoic Era Details
🦐 Early Paleozoic life was dominated by armored arthropods like trilobites, while terrestrial life was less developed; extant survivors include sea lilies and starfish.
🌍 A major event at the end of the Paleozoic was the convergence of all landmasses into the supercontinent Pangaea, leading to severe drought, lack of oxygen, and volcanic activity, causing the extinction of about 95% of life forms.

Mesozoic Era (Age of Dinosaurs)
🦖 The Mesozoic era ("middle life") began after the mass extinction, marked by the rise of large reptiles. The early Triassic period featured survivors like *Lystrosaurus* and marine reptiles like *Ichthyosaurus*.
🦕 During the Jurassic period (200 to 175 million years ago), Pangaea split into Laurasia (north) and Gondwana (south); this period marked the peak dominance of large dinosaurs like *Diplodocus* and *Brachiosaurus*.
☄️ The final Mesozoic period, the Cretaceous, ended with the rapid Cretaceous-Paleogene Extinction Event in less than one million years, wiping out dinosaurs after they dominated for approximately 160 million years.

Neozoic Era (Cenozoic)
🏔️ Starting about 60 million years ago, the Neozoic era saw the decline of giant reptiles and the rise of mammals, divided into the Tertiary and Quaternary periods.
🐒 The Tertiary period featured tropical climates initially, the emergence of primates, and the appearance of ancient horse species like *Pliohippus* and ancestors of the Mastodon (*Mammut*).
❄️ The early Quaternary, the Pleistocene (Ice Age) (approx. 2 million to 10,000 years ago), was characterized by cold climates and thick-furred animals like woolly rhinoceroses and saber-toothed tigers.

Quaternary Period Shift
💧 The later Quaternary period, Holocene (Alluvium or "Flood Age"), followed the melting of polar and mountain ice due to warming, causing sea levels to rise and separating the Indonesian archipelago from mainland Asia and Australia.
🌋 The Nglanggeran Ancient Volcano in Indonesia is cited as evidence witnessing the climate change leading up to the Ice Age, forming around the mid-Tertiary period.

Key Points & Insights
➡️ Prehistoric eras are classified both geologically (rock age) and archaeologically (historical remains).
➡️ The Cambrian explosion represents the period with the highest rate of evolution in Earth's history.
➡️ The mass extinction at the end of the Paleozoic wiped out ~95% of life due to the formation of Pangaea, drought, and volcanic activity.
➡️ The rise of mammals and the beginning of evidence suggesting the presence of early human ancestors occurred near the end of the Tertiary period.

📸 Video summarized with SummaryTube.com on Nov 09, 2025, 12:33 UTC