Fossil Vocabulary

1.)Paleontologist (70) – Scientist who studies fossils.

2.) Principle/ Law of Superposition (78)-

In undisturbed layers of rock, the oldest layers are found on the bottom and the youngest on the top.

3.)Relative Age/ Dating (79) - Its age in comparison to the age of other things.

4.)Index Fossil (75) -

The remains of species that existed on Earth for relatively short periods of time, were abundant, and were widespread geographically.

5.)Trilobites (100/105) -Small, hard-shelled organisms that crawled on the seafloor and sometimes swam through the water. They are considered to be index fossils.

6.)Extinction Causes:

Natural Causes-Meteorite colliding with Earth, Mass volcanic activity, draught, climate change (leading to loss of vegetation/habitat), Intro. Of predator due to natural causes i.e. migration

Man-made Causes-

Pollution, Deforestation/Habitat destruction, Hunting, New predators

7.) Geologic Time Scale (100) – The division of Earth’s history.

8.) Era (101) - Next to Eons, the longest subdivisions, which are marked by major, striking, and worldwide changes in the types of fossils present.

9.) Period (101) - Units of geologic time characterized by the types of life existing worldwide at the time, Eras are divided into these.

10.) Epoch (101) - When periods are divided into smaller units of time.

11.) Precambrian (108) -The longest part of Earth’s history which lasted from 4.5 billion years ago to about 544 million years ago. Not many fossils at all.

12.) Paleozoic (110) –

  • “Era of ancient life”.
  • An abundance of organisms with hard parts, such as shells, marked the beginning of this era.
  • Many marine fossils due to shallow seas covering a large part of Earth.
  • Vertebrates, amphibians, and reptiles evolved during this era.

13.) Mesozoic (116) –

  • “Era of Middle Life”
  • Pangaea began to break apart.
  • Reptiles and Dinosaurs evolved.
  • Birds, Mammals, Gymnosperms/ Non-Flowering Plants (ex. Pine trees), and Angiosperms/ Flowering Plants.

14.) Cenozoic (120)-

  • “Era of Recent Life”
  • Climate became cooler and “ice ages” occurred.
  • Alps, Andes and Himalayan Mountains were created.
  • Large Mammals- Elephants, horses, camels, deer, humans, kangaroos, koala’s (marsupials).

15.) Present day Earth:

Cenozoic Quaternary Holocene

Era Period Epoch

END OF MESOZOIC- Meteorite collided with Earth, causing a huge dust cloud to rise into the atmosphere, blocking out the Sun.

END OF PALEOZOIC- meteorite and/or changes in climate and lowering of sea-level due to the formation of Pangaea. More land, less seas meaning less marine life.