Compare Biodiversities

Purpose:  Having experienced two field trips, i.e., exploring both wetlands and oceans

(Activity 1), students are now in a position to compare and contrast the biodiversity of

these two ecosystems using a graphic organizer (Venn diagram).  Once students have

made this comparison/contrast, they will become aware of how another ecosystem

(estuaries), overlap between wetlands and oceans in both biotic and abiotic

characteristics.  Note: This activity builds from Lesson 3. 


Key concepts:  ecosystems, biodiversity, wetlands, freshwater, oceans, compare

(similar), contrast (different), overlap, estuary, biotic, and abiotic characteristics.


Materials:  Ecosystem books (wetlands and oceans), revisit Internet web-sites on

wetlands and oceans, Venn diagram, Smartboard, whiteboard, or butcher paper, markers,

and pencils.


  • Ask students if they recall the meaning of the key concepts, many of which were introduced in Lesson 3: ecosystem, biodiversity, biotic, and abiotic.
  • Use a Venn diagram (whole class on a Smartboard, whiteboard, or large piece of butcher paper) to compare and contrast the biotic characteristics (animals) of each ecosystem.
  • Students can revisit the Internet and/or their Ecosystem books to facilitate their memory.
  • They can also reflect on their observations of wetlands and oceans from the field trips at the Watsonville wetlands and Monterey Bay Aquarium (Lesson 4: Activity 1).
  • Co-construct the Venn diagram together.  Point out to the students that the overlapping circle between each ecosystem is an estuary.  Co-construct the meaning of an estuary together and verify the meaning in a dictionary or website such as (for an Estuary Glossary).
  • Have students complete their own Venn diagram (see 3rd-5th Students’ work L4).
  • These can be showcased in the class for others to see (have fun)!  Note: Lots of sharing and dialogue is required for this activity.