Activity: Diversity of Species

Goals:

1. To examine the relative abundance of types of organisms on

Earth.

2. To represent the diversity of species on Earth using a bar

graph.

Background information: Here’s a challenge: Imagine if you can, every single living thing on Earth. There are millions of species of plants, reptiles, mammals, fish, shellfish, amphibians, insects, arachnids, and microorganisms. Try to imagine them all, on a planet teeming with life. Don’t forget to put yourself in the picture! Now think about what makes each of those species different from the others. Got a headache yet? Think about what makes them look and act different, what different kinds of habitats and climates they live in, what their different needs are, and how they interact with one another. If you can, imagine even what differences you’d like to see if you could look at each one through a very powerful microscope. If you can do this, you’ve got a good idea of what the term biodiversity means. It’s a mind-boggling concept, because it covers Earth’s variety of life in all its forms and processes. Biodiversity is really about the ways that life is organized and interacts on our entire planet. And that’s a lot to think about!

When most people speak of biodiversity, what they really mean is species diversity. Species is the lowest level of taxonomic classification. There are about 1.4 million named species on Earth, but we know that many unnamed species exist. The total number is probably between 5 and 15 million. Most of the evidence for numerous unnamed species comes from studies of insects in tropical rainforests: when the canopy of a tropical rainforest is fumigated and all the dead insects are collected, large numbers of previously unknown insects are frequently collected.

Materials: calculator, colored pencils, graph paper

Procedure:

  1. What I Know: Write at least one sentence describing what you know about the variety of life on Earth.
  1. Study the table provided and fill in the missing column. Calculate the percentage of total species for each group. To do this, divide the number of species for a group by the total number of species and then multiply by 100 to get the percentage.

# of species in a group X 100 = % of total species

1,411,900

3. Use your results to create a bar graph. Label your x-axis Diversity of VariousSpecies and the y-axis Percent. Create a bar for each group of species. Label the exact percentage for each group at the top of the bars. Be sure to use colored pencils to create the bar graph.

  1. What I Did: Briefly describe the procedure for this activity.
  1. What I Observed: This will include the completed table and your bar graph.

Table:

Type of Species / Number of Species / Percentage of Species
Bacteria / 4,800
Protists / 57,700
Fungi / 69,000
Plants / 248,400
Insects / 751,000
Other Animals / 281, 000
TOTAL / 1,411,900
  1. What I Learned: Write at least two sentences summarizing what you learned from this activity. Refer to the goals of the activity and provide examples or evidence from your data.
  1. What I Wonder:Write a “how” or “why” question that you still have about this topic or still wonder about?
  1. Questions:
  2. How many percentage points is each box on the graph equal to?
  1. Which group accounts for the most diversity of species on Earth?
  1. What percent would represent the entire animal kingdom’s contribution to biodiversity?