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Marine Biodiversity

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What is Biological Diversity or Biodiversity?

Biodiversity or biological diversity is defined by the United Nations Convention on Biological Diversity as:

The variability among living organisms from all sources, including, inter alia [among other things], terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems.

This convention was ratified by all countries worldwide with the exception of: Andorra, Brunei Darussalam, the Holy See, Iraq, Somalia, Timor-Leste, and the United States of America.

Within this definition, there are 3 distinct levels of biodiversity:

Today's biodiversity is the result of billions of years of evolution, natural processes, and in more recent years, human activity. Before the advent of Homo sapiens, the Earth's biodiversity was much greater than it is today. Human activity has had a tremendous impact on biodiversity due to use of Earth's resources and exponential population growth.

The total number of species on Earth today is estimated to be around 10 million different species, but could be as low as 2 or as high as 100 million. New species are discovered often, and many that have been discovered have not yet been classified. The richest sources of biodiversity on Earth are found in tropical rainforests and the ocean.

Why is biodiversity important?

All species are an integral part of their ecosystem by performing specific functions that are often essential to their ecosystems and often to human survival as well. Some of the functions different species provide are to:

Ecosystem diversity is important for primary production in terms of:

Removing species from ecosystems removes those important functions. Therefore, the greater the diversity of an ecosystem the better it can maintain balance and productivity and withstand environmental stressors.

Biodiversity is important economically in terms of:

Biodiversity has an intrinsic value because all species:

We have an ethical responsibility to protect biodiversity. Biodiversity is important to science because it helps us understand how life evolved and continues to evolve. It also provides an understanding on how ecosystems work and how we can help maintain them for our own benefit.

© David Hall/

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