Extreme Deep Teacher's Guide.pdf - Evergreen Exhibitions

Build a Deep-Sea Vent
OBJECTIVES
Students will discover that...
■ hydrothermal vents are complex communities
made up of producers, consumers and
decomposers.
■ hydrothermal vent communities are as complex
and interdependent as communities on land.
BACK
CKGROUND
INFORMA
RMATION
S U B J E C T S
life science, art
G R A D E S
K - 6
C O N C E P T S
ecosystems
D U R A T I O N
several 30- to 45-minute class sessions
The discovery in 1977 of lush, complex communities at hydrothermal vent sites in the deep sea
surprised scientists. Until that time, they believed the deep sea was sparsely inhabited. They
believed this was because of a lack of food. When they discovered giant tubeworms, fishes, crabs,
limpets, and other organisms thriving in communities based on bacteria rather than plants,
scientists were forced to rethink their ideas that all life is based on energy from the sun. They had
found evidence that energy from the Earth itself could sustain life.
On land and in shallow waters, plants convert carbon dioxide and water into sugar using energy
from the sun. This process is called photosynthesis. Animals eat the plants, or they eat other
animals. When plants and animals die, decomposers reduce their remains into nutrients that plants
can use. Because plants are the original food makers, they’re called producers. Animals that eat
plants or other animals are consumers. The clean-up crew — bacteria and fungi — are
decomposers.
In the ocean, most life follows a similar regime. Most deep-sea organisms rely on organic matter
drifting down from above. You can trace the origins of that organic matter to photosynthesis. But in
certain parts of the deep sea, where volcanic activity creates hydrothermal vents, bacteria
metabolize volcanic chemicals and use the resulting energy to produce food. At deep-sea
hydrothermal vents, there are no plants. Bacteria take their place as producers.
With this activity, your students will have a chance to explore the amazing world of hydrothermalvent
communities by building a model of one in the classroom. You can use the materials we’ve
suggested here or come up with some creative ideas of your own.
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