NEOGENE

The Neogene period is a geological era that began about 23.03 million years ago and ended about 2.58 million years ago. It is part of the Cenozoic era and followed the Paleogene period.

 

During the Neogene period, the climate continued to cool from the warmth of the preceding Paleogene period, leading to the formation of ice caps on Antarctica and the northern hemisphere. This cooling trend contributed to the diversification and expansion of grasslands, which in turn influenced the evolution of herbivores such as horses, elephants, and giraffes.

 

One of the significant events that occurred during the Neogene period was the rise of the hominids, including the evolution of the human lineage. The earliest known human ancestors, such as Sahelanthropus and Orrorin, appeared during this era, and by the end of the Neogene, the first members of the Homo genus had emerged.

 

The Neogene period was also marked by significant geological events such as the uplift of the Andes and the formation of the Himalayas. Additionally, the formation of the Mediterranean Sea occurred during this period, as well as the closing of the Tethys Sea.

 

PALEOGENE

 

The Paleogene period is a geological era that began about 66 million years ago and ended approximately 23.03 million years ago. It is part of the Cenozoic era and followed the Mesozoic era, which ended with the mass extinction event that wiped out the dinosaurs.

 

During the Paleogene period, the Earth's climate was generally warm and stable, with a few brief cooling periods. The beginning of the Paleogene was marked by the recovery of life on Earth after the mass extinction event, with the emergence of new plant and animal species. Mammals, which had existed during the Mesozoic era, began to diversify and evolve into new forms, such as primates, horses, and whales.

 

One of the significant geological events that occurred during the Paleogene period was the formation of the Atlantic Ocean as the continents continued to drift apart. Additionally, the collision of the Indian and Eurasian plates led to the formation of the Himalayas, which had a significant impact on the Earth's climate.

 

The Paleogene period is also known for several notable events, including the appearance of the first primates in the fossil record, the diversification of birds, and the emergence of new types of flowering plants. Finally, the end of the Paleogene was marked by a series of cooling events, which ultimately led to the onset of the Neogene period.

CRETACEOUS

The Cretaceous period is a geological era that lasted from approximately 145 to 66 million years ago. It is the last and longest period of the Mesozoic era, following the Jurassic period and preceding the Paleogene period of the Cenozoic era.

 

During the Cretaceous period, the Earth's climate was generally warm and humid, with high atmospheric CO2 levels contributing to a greenhouse effect that kept global temperatures high. The period saw the evolution and diversification of many new groups of organisms, including flowering plants, birds, and dinosaurs.

 

One of the significant events of the Cretaceous period was the diversification and radiation of dinosaurs. Some of the most well-known dinosaurs, such as Tyrannosaurus rex, Triceratops, and Velociraptor, lived during this time. The Cretaceous period also saw the emergence of many types of marine reptiles, such as mosasaurs and plesiosaurs.

 

The end of the Cretaceous period is marked by the mass extinction event that wiped out the non-avian dinosaurs and many other groups of organisms. The cause of this extinction event is still debated, but a combination of factors such as volcanic activity, asteroid impacts, and climate change may have contributed to the decline of many species.

 

JURASSIC

The Jurassic period is a geological era that lasted from approximately 201 to 145 million years ago. It is the middle period of the Mesozoic era, following the Triassic period and preceding the Cretaceous period.

 

During the Jurassic period, the Earth's climate was generally warm and humid, with high levels of atmospheric CO2 leading to a greenhouse effect that kept global temperatures high. This period saw the evolution and diversification of many new groups of organisms, including dinosaurs, mammals, and plants.

 

One of the significant events of the Jurassic period was the diversification and radiation of dinosaurs, with many new species evolving and spreading across the Earth. Some of the most well-known dinosaurs, such as Stegosaurus and Brachiosaurus, lived during this time. Additionally, the first true mammals appeared during the Jurassic period, though they were small and relatively insignificant compared to the dominant reptilian groups.

 

The Jurassic period was also a time of significant geological activity, with the continued separation of the supercontinent Pangaea leading to the formation of new oceans and mountain ranges. The breakup of Pangaea ultimately led to the formation of the Atlantic Ocean and the emergence of many new land masses.

 

TRIASSIC

The Triassic period is a geological era that lasted from approximately 251 to 201 million years ago. It is the first period of the Mesozoic era, following the Permian period and preceding the Jurassic period.

 

During the Triassic period, the Earth's climate was generally warm and dry, with vast deserts covering much of the supercontinent Pangaea. This period saw the evolution and diversification of many new groups of organisms, including dinosaurs, mammals, and plants.

 

One of the significant events of the Triassic period was the diversification and radiation of archosaurs, a group of reptiles that includes the ancestors of modern crocodiles, birds, and dinosaurs. Some of the earliest dinosaurs and mammals also appeared during this time, though they were relatively small and insignificant compared to the dominant reptilian groups.

 

The Triassic period was also a time of significant geological activity, with the continued formation of Pangaea leading to the development of new mountain ranges and the opening of new oceans. Additionally, the period was marked by several mass extinction events, including the end-Permian extinction, which wiped out over 90% of all marine species.

PERMIAN

The Permian period is a geological era that lasted from approximately 299 to 251 million years ago. It is the last period of the Paleozoic era, preceding the Triassic period of the Mesozoic era.

 

During the Permian period, the Earth's climate was generally warm and dry, with vast areas of desert covering much of the supercontinent Pangaea. This period saw the evolution and diversification of many new groups of organisms, including reptiles, insects, and plants.

 

One of the significant events of the Permian period was the diversification and radiation of synapsids, a group of reptiles that includes the ancestors of modern mammals. Additionally, the period saw the emergence of many new types of reptiles, including the dominant therapsids and the early archosaurs that would give rise to the dinosaurs.

 

The Permian period was also a time of significant geological activity, with the continued formation of Pangaea leading to the development of new mountain ranges and the opening of new oceans. However, the end-Permian extinction event, which occurred approximately 252 million years ago, was one of the most significant extinction events in Earth's history, wiping out over 90% of all marine species and 70% of terrestrial species.

 

CARBONIFEROUS

The Carboniferous period is a geological era that lasted from approximately 359 to 299 million years ago. It is the fifth period of the Paleozoic era, following the Devonian period and preceding the Permian period.

 

During the Carboniferous period, the Earth's climate was generally warm and humid, with vast areas covered by dense forests. This period saw the evolution and diversification of many new groups of organisms, including amphibians, insects, and plants.

 

One of the significant events of the Carboniferous period was the evolution and diversification of seed plants, which gave rise to the first forests. These forests were dominated by tree-like plants known as lycophytes and ferns, which produced vast amounts of organic material that would eventually be buried and transformed into coal.

 

The Carboniferous period was also a time of significant geological activity, with the continued movement of tectonic plates leading to the formation of new mountain ranges and the opening of new oceans. Additionally, the period saw several glaciation events, which had a significant impact on the global climate and sea levels.

 

DEVONION

The Devonian period is a geological era that lasted from approximately 419 to 359 million years ago. It is the fourth period of the Paleozoic era, following the Silurian period and preceding the Carboniferous period.

 

During the Devonian period, the Earth's climate was generally warm and humid, with extensive shallow seas and wetlands covering much of the supercontinent Gondwana. This period saw the evolution and diversification of many new groups of organisms, including jawed fish, plants, and insects.

 

One of the significant events of the Devonian period was the diversification of fish, with the emergence of several new groups, including the placoderms and the first sharks. Additionally, the Devonian period saw the emergence of the first amphibians, which were the first tetrapods to leave the water and live on land.

 

The Devonian period was also a time of significant geological activity, with the continued movement of tectonic plates leading to the formation of new mountain ranges and the opening of new oceans. Additionally, the period saw several periods of sea level changes, which had a significant impact on the distribution and evolution of marine organisms.

 

SILURIAN

The Silurian period is a geological era that lasted from approximately 443 to 419 million years ago. It is the third period of the Paleozoic era, following the Ordovician period and preceding the Devonian period.

 

During the Silurian period, the Earth's climate was generally warm and mild, with the first signs of a stable and predictable climate. This period saw the evolution and diversification of many new groups of organisms, including jawless fish, land plants, and marine invertebrates such as brachiopods and crinoids.

 

One of the significant events of the Silurian period was the emergence of the first vascular plants, which were able to grow taller and more complex than their predecessors. These plants, along with the emergence of fungi that could break down their cellulose cell walls, played a significant role in shaping the terrestrial ecosystems of the time.

 

The Silurian period was also a time of significant geological activity, with the continued movement of tectonic plates leading to the formation of new mountain ranges and the opening of new oceans. Additionally, the period saw several glaciation events, which had a significant impact on the global climate and sea levels.

 

ORDOVICIAN

The Ordovician period is a geological era that lasted from approximately 485 to 443 million years ago. It is the second period of the Paleozoic era, following the Cambrian period and preceding the Silurian period.

 

During the Ordovician period, the Earth's climate was generally warm and mild, with the first signs of a stable and predictable climate. This period saw the evolution and diversification of many new groups of organisms, including early jawless fish, trilobites, and marine invertebrates such as brachiopods and corals.

 

One of the significant events of the Ordovician period was the diversification of marine life, with the emergence of several new groups of animals such as cephalopods, bryozoans, and crinoids. Additionally, the Ordovician period saw the continued evolution and diversification of trilobites, which were among the most successful and diverse groups of animals during this time.

 

The Ordovician period was also a time of significant geological activity, with the continued movement of tectonic plates leading to the formation of new mountain ranges and the opening of new oceans. Additionally, the period saw several glaciation events, which had a significant impact on the global climate and sea levels.

 

CAMBRIAN

The Cambrian period is a geological era that lasted from approximately 541 to 485 million years ago. It is the first period of the Paleozoic era, which is known as the "Age of Invertebrates" due to the significant diversification of invertebrate life during this time.

 

The Cambrian period saw the emergence and diversification of many new groups of organisms, including the first complex animals with hard shells, such as trilobites and brachiopods. This period also saw the emergence of the first chordates, which are considered to be the earliest ancestors of vertebrates.

 

One of the most significant events of the Cambrian period was the "Cambrian Explosion," which was a rapid diversification of life that occurred during this time. During this period, many new body plans and forms of locomotion evolved, which laid the foundation for the vast diversity of life that we see today.

 

The Cambrian period was also a time of significant geological activity, with the formation of new continents and the opening of new oceans. Additionally, the period saw several glaciation events, which had a significant impact on the global climate and sea levels.

 

 

The Proterozoic eon is a geological era that lasted from approximately 2.5 billion to 541 million years ago, preceding the Phanerozoic eon (which includes the Paleozoic, Mesozoic, and Cenozoic eras).

 

During the Proterozoic eon, the Earth underwent significant geological and biological changes. The first continents emerged, and the atmosphere and oceans underwent significant changes due to the evolution of photosynthetic organisms, such as cyanobacteria, which released oxygen as a byproduct. This oxygenation of the Earth's atmosphere led to the evolution of new groups of organisms, such as eukaryotes, which have complex cells with a nucleus and organelles.

 

One of the significant events of the Proterozoic eon was the emergence of multi-cellular organisms, which laid the foundation for the later diversification of life during the Phanerozoic eon. Additionally, the Proterozoic eon saw the formation of significant mineral deposits, including iron, copper, and gold, which have been economically important throughout human history.

 

The Proterozoic eon is divided into three subdivisions: the Paleoproterozoic, Mesoproterozoic, and Neoproterozoic. Each subdivision is characterized by significant geological and biological events, including the emergence of new groups of organisms, the formation of new continents, and the evolution of new geological processes.