Have you ever wondered how many species live on Earth? Earth is full of amazing creatures. In this lesson, you will learn about the importance of species diversity. At the end, test your knowledge with a quiz.
Definition of Species Diversity
Imagine chasing a horned lizard, and it uses a bizarre tactic to deter you, squirting blood at you out of its eye. Imagine scuba diving and encountering one of the ugliest fish in the world, called the anglerfish.
This is not science fiction; this is real. There are some bizarre creatures that call Earth home. The diversity of creatures roaming Earth is absolutely astounding.
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Species diversity is defined as the number of species and abundance of each species that live in a particular location.
The number of species that live in a certain location is called species richness. If you were to measure the species richness of a forest, you might find 20 bird species, 50 plant species, and 10 mammal species. Abundance is the number of individuals of each species. For example, there might be 100 mountain beavers that live in a forest. You can talk about species diversity on a small scale, like a forest, or on a large scale, like the total diversity of species living on Earth.
Species Diversity of Earth
How many species do you think live on Earth? There are approximately 1.
8 million different species classified on Earth. Of all the species identified, nearly one million are insects! New species are being discovered each year. Scientists estimate that there may be between 5 to 30 million species that actually live on Earth. Each year, approximately 13,000 more species are added to this growing list of known species. For example, in 2013, a species of a venomous snake called the green palm-pit viper was discovered in the country of Honduras.
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In 2014, a carnivorous mammal species called olinguito was discovered in Colombia and Ecuador. Who knows what weird creature might be discovered this year!
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The hottest spots for species diversity are tropical rainforests. Tropical rainforests comprise only 7% of all land on Earth yet are home to nearly 50% of all the species on Earth! In Costa Rica, there are over 1,400 species of orchids, 1,200 species of butterflies, and 600 species of birds! Interesting species of mammals live here as well, like howler monkeys, jaguars, and sloths.
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Terms | Explanations |
---|---|
Species diversity | the number of species and abundance of each species that live in a particular location |
Species richness | the number of species that live in a certain location |
Abundance | the number of individuals of each species |
Learning Outcomes
Completing this lesson should help you with the following:
- Describe species diversity
- Identify diversity richness
- Recognize the importance of abundance in diversity