Amazon.com: NewPath Learning-947122 Geologic Time Scale Visual ... - Free Printable

The image provided is a worksheet titled "Geologic Time Scale." The task involves filling in information about the geologic time scale, including eras, periods, millions of years ago, and lifeforms that existed during those times. Below is a detailed explanation and solution for each section:

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Section 1: What is a geologic time scale?

- Definition: The geologic time scale is a system used by geologists to describe the timing and relationships between events that have occurred throughout Earth's history. It divides Earth's history into segments based on significant geological or biological events.

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Section 2: Broad divisions of the geologic time scale

- Eons: The broadest divisions of the geologic time scale are called eons.
- Eras: Eons are divided into eras.
- Periods: Eras are divided into periods.
- Epochs: Periods are divided into epochs.

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Section 3: Filling in the table

#### The Cenozoic Era
- Millions of Years Ago: 1.8 million years ago to present
- Description: The Cenozoic Era is often referred to as the "Age of Mammals." During this era, mammals diversified and became dominant on land. Humans also evolved during this time.
- Lifeforms:
- Mammoth: A large prehistoric mammal with long tusks.
- Sabertooth Tiger: A predatory cat with long, saber-like canine teeth.
- Horse: Modern horses evolved during this era.
- Human: Homo sapiens (modern humans) evolved in the late Cenozoic Era.

#### The Mesozoic Era
- Millions of Years Ago: 252 million to 66 million years ago
- Description: The Mesozoic Era is known as the "Age of Dinosaurs." It was characterized by the dominance of dinosaurs on land, pterosaurs in the sky, and marine reptiles in the oceans.
- Lifeforms:
- Pterodactyl: A flying reptile with wings made of skin stretched over elongated fingers.
- Triceratops: A herbivorous dinosaur with three horns and a frill on its head.
- Velociraptor: A small, agile carnivorous dinosaur.
- Tyrannosaurus Rex: A large, carnivorous dinosaur known for its massive size and powerful jaws.
- Brachiosaurus: A large sauropod dinosaur with a long neck and tail.
- Mosasaur: A large marine reptile that lived in the oceans.

#### The Paleozoic Era
- Millions of Years Ago: 541 million to 252 million years ago
- Description: The Paleozoic Era is marked by the emergence and diversification of early life forms, including the first fish, amphibians, reptiles, and insects. It ended with the largest mass extinction event in Earth's history, the Permian-Triassic extinction.
- Lifeforms:
- Shark: Early sharks appeared during the Paleozoic Era.
- Dragonfly: Insects like dragonflies were abundant.
- Coelacanth: An ancient fish that lived during this era.
- Ammonite: A marine cephalopod with a coiled shell.
- Nautilus: A marine cephalopod with a spiral shell.
- Trilobite: An extinct marine arthropod with a hard exoskeleton.

#### Precambrian
- Millions of Years Ago: 4.6 billion to 541 million years ago
- Description: The Precambrian represents the vast majority of Earth's history before the Cambrian Period. Life during this time was primarily single-celled organisms, though some multicellular life forms emerged toward the end.
- Lifeforms:
- Bacteria: Simple, single-celled organisms that were among the first life forms on Earth.
- Algae: Early photosynthetic organisms.
- Corals: Ancient coral-like organisms.
- Sponges: Simple multicellular animals.
- Insects: Early insects began to evolve near the end of the Precambrian.

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Key Vocabulary Terms

- Cambrian Period: Part of the Paleozoic Era, known for the "Cambrian Explosion," when many animal phyla first appeared in the fossil record.
- Carboniferous Period: Part of the Paleozoic Era, known for the formation of coal deposits.
- Cretaceous Period: Part of the Mesozoic Era, known for the last appearance of dinosaurs.
- Devonian Period: Part of the Paleozoic Era, known as the "Age of Fishes."
- eon: The largest division of geologic time.
- era: A major division of geologic time, smaller than an eon.
- epoch: A subdivision of a period.
- geologic time scale: The system used to describe Earth's history in terms of time.
- Jurassic Period: Part of the Mesozoic Era, known for dinosaurs like Brachiosaurus and Stegosaurus.

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Final Answer

Here is the completed table:

| Era | Period | Millions of Years Ago | Lifeforms |
|------------------------|---------------------|----------------------------|--------------------------------------------------------------------------------|
| The Cenozoic Era | | 1.8 to present | Mammoth, Sabertooth Tiger, Horse, Human |
| The Mesozoic Era | | 252 to 66 million | Pterodactyl, Triceratops, Velociraptor, Tyrannosaurus Rex, Brachiosaurus, Mosasaur |
| The Paleozoic Era | | 541 to 252 million | Shark, Dragonfly, Coelacanth, Ammonite, Nautilus, Trilobite |
| Precambrian | | 4.6 billion to 541 million | Bacteria, Algae, Corals, Sponges, Insects |

Boxed Final Answer:
\boxed{\text{See the completed table above.}}