Click on the page icon for Lesson 1 in Adobe Acrobat format (90K). Includes Take-Home Pages.

Objectives

• Identify environmental conditions of the rocky coast of Maine and the coral reefs of the Caribbean.
• Interpret the relations among latitude, temperature, and sunlight within the two ecosystems.
• Predict the location of marine ecosystems with similar environmental conditions.

Materials

• Copies of Take-Home Pages.
• Globe or large world map.

Subjects

Science, social studies

Procedure

1. Have students imagine they are going on a trip to the coast (to a famous resort or less visited spot) or designing a travel poster for a beach vacation. Ask them to think of words that characterize this location (e.g., beach, sand, surf, or waves) and have them describe the weather conditions they would expect to find there.

2. Using a globe or world map, ask students to locate the places that the class has mentioned. Then ask them to find the coast of Maine and the islands of the Caribbean, two locations that they will later compare in detail. Review the concept of latitude, measured in imaginary lines that circle the globe parallel to the equator. (Latitude increases as one travels north or south toward the poles and away from the equator, which is located at zero degrees latitude.) Have students estimate the latitude of each location they found on the map or globe. (Maine and the islands of the Caribbean are located at about forty-five and twenty-five degrees north latitude, respectively.) Ask students which location is closer to the equator and has a warmer, sunnier climate (the Caribbean); which probably has a cold winter (Maine); and which has the same warm temperatures all year long (the Caribbean).

3. Ask students to name an instrument that measures temperature (thermometer) and have them discuss briefly how temperature affects their daily lives (e.g., in deciding how to dress according to the weather). Ask your students if they know the names of the two most common temperature scales (Fahrenheit and Celsius). Then ask them how winter temperatures in Maine might be different from those in the Caribbean. (Maine has colder winter temperatures.) Would they expect to see the same plants and animals in each place? (No: Some animals live better in cold places, and others in warm.) Tell your students that temperatures limit the kinds of organisms that can live in a given location. Stress that close-in currents, which act like rivers flowing within the oceans, also influence a coastal region's temperature. Currents that begin near the equator, like the Northern Equatorial or the Gulf Stream, are warm. Currents that begin in Greenland or Labrador (show these locations on a globe) begin closer to the North Pole and are cold. (For more information on currents, oceans, and weather, see Art to Zoo, September/October 1995, Tomorrow's Forecast: Oceans and Weather.)

4. Hand out copies of the Take-Home pages. After students have completed the exercises individually, review the correct answers. Ask your students to predict which of the two locations has the greater average amount of sunlight. (Be sure to remind students that the equator has a latitude of zero degrees and that lower latitudes generally have warmer climates and more hours of direct sunlight.) Tell your students that sunlight is the source of energy that fuels each living community or ecosystem. Plants use the Sun's energy, nutrients in the water, and carbon dioxide to produce sugars that animals then eat. To conclude the lesson, ask students to predict the temperature conditions of other locations along the Atlantic coast as shown on the map. Students will conclude that coral reefs are located close to the equator and that rocky, temperate coasts are further north.