Current Events

  • Atmospheric CO2 Level Tops 400 ppm
    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm rep...Read more

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    Atmospheric CO2 Level Tops 400 ppm

    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm repeatedly. Daily levels of CO2 can vary due to weather, and there are seasonal trends as well. The level of atmospheric greenhouse gases continues to increase, now over 120 ppm since the Industrial Revolution began. For more on the Keeling Curve, see http://keelingcurve.ucsd.edu/. Find out more about greenhouse gases and warming.
  • Massive Tornado Outbreak on Tornado Alley
    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Io...Read more

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    Massive Tornado Outbreak on Tornado Alley

    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Iowa, Illinois and Missouri. On May 20th, a massive tornado struck Moore, Oklahoma, devastating communities - destroying over 100 homes and hitting two elementary schools and a hospital - with many casualties and deaths. Our thoughts are with our friends and colleagues suffering from these storms. For more on the May 20th storms, see the NOAA Storm Prediction Center Storm Report.
  • Kansas Legislator Proposes Bill to Outlaw Sustainability Education
    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of ...Read more

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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.
This picture is an example of early autotrophs.
Click on image for full size
Image courtesy of Corel Photography

Early Life

Over a very long time, gradual changes in the earliest cells gave rise to new life forms. These new cells were very different from the earlier heterotrophs because they were able to get their energy from a new source -- the Sun.

Organisms that are able to make their own food (in the form of sugars) by using the energy of the Sun are called autotrophs, meaning "self-feeders". Photosynthesis is the name of the process by which these autotrophs use energy from the sun and eat.

Because the autotrophic bacteria were able to feed themselves by using the energy of the Sun, they were no longer dependent on the same limited food supply as their ancestors and were able to flourish. Over millions of years of evolution, photosynthetic bacteria eventually gave rise to modern day plants.

The appearance of organisms capable of performing photosynthesis was very significant -- if it weren't for the photosynthetic activity of these early bacteria, Earth's atmosphere would still be without oxygen and the appearance of oxygen-dependent animals, including humans, would never have occurred!

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Traveling Nitrogen is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.

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Traveling Nitrogen Classroom Activity Kit

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

Photosynthesis

Photosynthesis is the name of the process by which autotrophs (self-feeders) convert water, carbon dioxide, and solar energy into sugars and oxygen. It is a complex chemical process by which plants and...more

The First Living Cells

The first beings were probably much like coacervates. As a group, these bacteria are called heterotrophic anaerobes (ann-air-robes). Because there was virtually no oxygen in the atmosphere at this time,...more

Kingdom Plantae

Kingdom Plantae contains almost 300,000 different species of plants. It is not the largest kingdom, but it is a very important one! In the process known as "photosynthesis", plants use the energy of the...more

The Archean

The Archean is the name of the age which began with the forming Earth. This period of Earth's history lasted a long time, 2.8 billion years! That is more than half the expected age of the Earth! And no...more

Iron Ore Deposits

Eventually, photosynthesis by the earliest forms of plant life (a form of life capable of feeding itself instead of feeding off of others) began to produce significant amounts of oxygen. One important...more

Extreme Environments

Extreme environments are places where "normal" life finds it hard to survive. That doesn't mean that there isn't any life in extreme environments. Certain creatures can live and grow in extreme environments....more

Extremophiles

Some environments are not good homes for most "normal" kinds of life. Places like that are called extreme environments. That doesn't mean that there isn't any life in extreme environments. Certain creatures...more

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