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Animals that exhibit radial symmetry, tissues but no organs and possess stinging cells called nematocysts.

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How Do You Control For The World?
Teacher Contributed

How Do You Control The World?

High CO2 Vents courtesy of © Australian Institute of Marine Science" and Katharina Fabricius

Bubbles Can Help

Levels of CO2 worldwide are increasing which presents challenging problems for scientists trying to determine how this change will affect humans and the planet. Scientists love experiments. Nice experiments where you can control all variables relevant to your hypothesis and just change one at a time to see the effect of that variable. But how does one set up an experiment like that when you’re dealing with a planet?

Fortunately, at least for how the CO2 is affecting the oceans, scientists have found a way to address some of their questions.

But there is more to the oceans than coral reefs. Look here to learn how the outlook is for sea anemones (another type of Cnidarian)

Look here to see the outlook for a temperate location

Look here for even more variety in the response of organisms

Extension Investigation

  1. Using the Papuan CO2 seep as your laboratory, design an experiment to see how organisms will be affected by rising ocean acidity. The simplest experiment involves organisms that make calcium carbonate shells but don’t feel the need to limit yourself to questions of this nature. Any question is fair game just remember you want to control your variables as much as possible.
  2. Both corals and sea anemones belong to the phylum Cnidaria and have different symbiotes that help them survive. How do the differences between their symbiotes affect how they respond to increased acidity?

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