Happenings During the Cenozoic (65 Million Years Ago to Present)

Time:

65 million years ago to today (and continuing!)
(See the geologic timescale!)

Paleogeography:

  • The Atlantic Ocean continues to widen as new ocean crust is formed at the Mid Atlantic Ridge.
  • India collided with the Asian continent forming the Himalayan Mountains which continue to grow higher today.
  • The African plate pushed into Europe forming the Alps.
  • In North America, the Rocky Mountains formed and the Colorado Plateau was uplifted.

Climate:

  • Early Cenozoic climate was warm and humid and the climate cooled gradually during the Cenozoic.
  • During the past two million years, Earth's climate has cooled and warmed over and over again. The cool times are called Ice Ages because large amounts of ice formed on land. The last time that these sheets of ice were very large was 20,000 years ago. Most of the sheets of ice melted by about 10,000 years ago.
  • Whenever climate cooled and ice sheets formed on land, there was less water left in the oceans, thus lower sea level. Sometimes lower sea level caused land that is usually underwater to connect continents. These areas of land, called land bridges, allowed animals to migrate to other continents.

Evolutionary Events:

  • Mammals, which had been small and few during the Mesozoic, became more diverse. New mammal species evolved and were able to live in areas and eat foods that had been used by dinosaurs during the Mesozoic.
  • Grass evolved and was well adapted to the cooler climates of the late Cenozoic.
  • Horses and other species of grazing animals evolved and ate the newly-evolved grass. The first horses were small, about the size of a labrador retriever.
  • Modern humans and their recent ancestors are called hominids. Thousands of fossils of hominids have been found; the oldest is more than 6 million years old. Fossils of hominids that are similar to modern humans are called Homo sapiens. Fossils of Homo sapiens are as much as 400,000 years old.
Last modified June 1, 2005 by Lisa Gardiner.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Atacama Desert

The Atacama Desert is one of the driest places on Earth. The Atacama is in the country of Chile in South America. In an average year, much of this desert gets less than 1 millimeter (0.04 inch) of rain!...more

Scientists to Investigate Role of Equatorial Pacific Ocean in Global Climate System

An international team of scientists is currently studying the equatorial Pacific Ocean, and a second expedition will happen in May 2009. They are part of a science program called the Pacific Equatorial...more

What’s That Mineral?

Spotting minerals is fun! There are many different types of minerals, each with a different name and a special set of characteristics. So, if you find a mineral that you do not recognize, you can use...more

Quartz

Quartz is one of the most common mineral in Earth’s crust! Silica (Si) and Oxygen (O) are the only elements within pure quartz. If a cooling magma has silica leftover after feldspars form, quartz is likely...more

Mica Minerals

Mica minerals make some rocks sparkle! They are often found in igneous rocks such as granite and metamorphic rocks such as schist. They sparkle because light is reflected on their flat surfaces, which...more

Feldspar

Feldspar is the most common mineral in the Earth’s crust, so you are very likely to find it in the rocks you collect! It is found it all of the three rock types, but is most common in intrusive igneous...more

Olivine

Olivine looks like little green crystals. It is typically found in some igneous and metamorphic rocks. Often the crystals are so small that you need to use your hand lens or magnifying glass to see them...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA