Green World Hypothesis: What and How does it affect you?

What is the Green World Hypothesis? How does it work?

Green World Hypothese Background

United States scientists Nelson Hairston, Frederick Smith and Lawrence Slobodkin proposed the Green World Hypothesis in the 1960s. In short, the Green World Hypothesis is a hypothesis that claims that Predators are the key to keeping our world green, because they keep the numbers of plant-eating herbivores from growing out of control and consume all plants.

The Green World Hypothesis is helpful to understand sustainability in our world. It is also a good hypothesis to understand why biodiversity is an important subject to study.

In 1963, Professor Robert Paine stood on the shore of the Makah Bay in Washington. He observed a diverse community of species including purple and orange sea stars, mussels, barnacles, limpets, anemones and algae. Paine noted that the sea stars (Pisaster orchraceus) were at the top of the food chain in this community, and that mussels were the most important component of their diet. One observation from the experiment is that Paine observed biodiversity in the community diminish until the intertidal zone was dominated by a monoculture of mussels; the sea star’s prey.

Green World Hypothesis explained

It is a quite simple hypothesis actually, the assumptions are that

  1. the world is green, because we have lots of plants, which are green in color
  2. If we reduce the number of plants, then the world is “less green”
  3. One of the major factors that can reduce the number of green plants, is because there are animals that eats plants (herbivore population).
  4. The more herbivore are there on the planet, the more green they eat, and the less green the world is (because of less plants)
  5. If the number of herbivore is reduced, there will be more plants, hence more green
  6. One way to control the herbivore population is that they are consumed by predators that eat them.
  7. The more apex predators, the more herbivore animal they consume, the more control of the herbivore will let the plants to grow.

It is actually quite simple to understand, but not very easy to prove, because our world is a complex ecosystems.

Green World Hypothesis Examples

The good news is that we don’t really have to prove it to take advantage of the hypothesis.

In 1995, grey wolves were re-introduced to Yellowstone National Park. This has reduced the population of elk and changed their grazing habits, and aspen is now recovering.  

It is actually very similar to Habitat Control, The purpose of habitat management is to improve existing habitat to benefit wildlife. We can often increase the amount of wildlife in an area, improve their quality and health, and encourage them to use areas that they currently are not using just by manipulating the habitat. The work in Green World Hypothesis is similar but instead of controlling wildlife, we are assuming predator can help to maintain the world’s color through a sequence of cause and effects from predator to plant populations.

Conclusion

Our world made up of many complex ecosystem interactions. Even small removing pieces of the ecosystem can have profound and often unexpected consequences. We as human who has lots of influence on this planet, must be mindful and careful how we can impact our world and keep our planet sustainable.

What is the Green World Hypothesis?

The Green World Hypothesis is a hypothesis that claims that Predators are the key to keeping our world green, because they keep the numbers of plant-eating herbivores from growing out of control and consume all plants.

Learn more at Diversity.Social Sustainability site

About the author

Susanne Ricee

Susanne Ricee is the Diversity and Inclusion Specialist and Researcher at Diversity for Social Impact. Sue brings over 15 years of HR and Diversity, Equity, Inclusion consultation experience.
Sue's previous experience includes Microsoft, Target, and Kraft. Sue is also the manager of Diversity Leadership Directory