January 12-18, 2012, Current Events Lesson Plan
Current Event:
At least 23 new animal species have been discovered living around hydrothermal vents in the Southern Ocean, near Antarctica. The species include barnacles, sea anemones, starfish, snails, and yeti crabs.
Hydrothermal vents are areas where heated water flows from the ocean floor. The vents are about 8,000 feet (2,438 meters) beneath the surface.
Objective:
Hydrothermal vents provide energy to animals that live on the ocean floor. The Behind the Headlines news story and related World Book articles highlights the new species scientists have recently discovered and how they live using the hydrothermal vents.
Vocabulary Terms:
- Antarctica
- bacteria
- barnacles
- extremophiles
- hydrothermal vents
- ocean floor
- sea anemones
- snails
- Southern Ocean
- species
- starfish
- yeti crabs
Discussion Topics:
1. Living things are abundant around hydrothermal vents, but they also live in many other places on the ocean floor, where the water is extremely cold. As a result, we know that the warmth provided by hydrothermal vents does not explain why so many living things are found there. Why do your students think hydrothermal vents teem with life?
2. Hydrothermal vents are areas where heated water flows from the ocean floor. As the water cools, it releases chemicals that bacteria can use to make their own food. Animals provide the bacteria with a place to live in exchange for food. For example, the yeti crabs are covered in hairlike filaments that house the bacteria. This is called a symbiotic relationship. Explain what this concept is — including the three different forms of symbiosis: parasitism, commensalism, and mutualism — and how other species demonstrate this behavior (mosquitoes, clownfish and sea anemones, lichens, etc.).
3. Whales live near the surface, where most of them feed on plankton. When the whales die, they fall to the ocean floor, and many living things gather to feed on their remains. How is the energy provided by whales different from the energy provided by hydrothermal vents?
4. Organisms that live around hydrothermal vents do not depend on the sun for energy, unlike nearly all other life on Earth. Some scientists believe that life first arose around hydrothermal vents. Scientists also speculate that alien planets with harsh environments may support extraterrestrial life similar to the extremophiles found around hydrothermal vents. Read about Jupiter’s moon Europa. Explain why life on Europa might be similar to that found around hydrothermal vents.