Virtual Galápagos
Unit 2 Lesson 2: Island Climate and Currents
Tortoise Curriculum Lesson Plan
LEARNING GOALS AND OBJECTIVES:
- Goal 1: Students will be able to evaluate which vegetation zones provide food for each tortoise by comparing and contrasting the vegetation zones.
STANDARDS
Next Generation Science Standards
- 3-ESS2 Obtain and combine information to describe climates in different regions of the world.
- 3-ESS2.D. Weather and Climate: Climate describes a range of an area’s typical weather conditions and the extent to which those conditions vary over years
- 3-LS3-2. Use evidence to support the explanation that traits can be influenced by the environment.
KEY TERMS AND CONCEPTS
- Arid zone: Dry terrain with little rainfall and few plants
- Scalesia zone: Humid, forested terrain with lush vegetation
- Pampa zone: Humid, grassy terrain
- Climate: The average weather conditions in an area over a long period of time
- Prevailing winds: The direction in which weather is traveling
- Windward: The side of the island facing the wind
- Leeward: The side of the island facing away from the wind
- Humboldt Current: A current, from June to November that carries colder water up from the southern hemisphere
- Panama Current: A current, from January to June, that carries warm water from the equator to the Galápagos
- Garúa: A mist that typically forms at the tops of volcanoes as the cool air from over the Humboldt current blows up the side of the volcano and releases its water near the top of the island; garúa occurs during the dry season
PRIOR KNOWLEDGE AND SKILLS
- Students are encouraged to think about and share the observations they’ve made about how weather changes in the environments they’ve lived in.
ADVANCE PREP FOR TEACHER KNOWLEDGE
In the Galápagos, there are different types of vegetation zones on the islands. Smaller islands, like Santa Fe and Española, only have arid vegetation zones. These arid vegetation zones have limited rainfall throughout the year and have sparse vegetation, owing to the lack of water. The Opuntia cactus, also known as the prickly pear cactus, is commonly found in arid zones. The saddleback tortoises, like Becki, tend to live in arid zones because of the prevalence of the Opuntia cactus.
The pampa and scalesia zones are humid zones that get more rainfall and vegetation throughout the year. Scalesia zones are forested, with lush vegetation; pampa zones have more grassy vegetation. The domed tortoises, like Tomás, are often found in pampa vegetation zones because of easy access to the food source of low-lying grasses.
The Galápagos Islands experience different types of weather on different parts of the islands. On the windward sides of the islands, which is the side of the island facing the prevailing wind, the climate is cooler and more humid. The wind blows over the ocean, where it gathers moisture. The moisture-rich air, when it hits the islands, is forced to higher altitude (the highlands of the islands), where the cooler temperatures cause the air to release the water as precipitation, a type known as garúa. Garúa is a mist that is almost like rain, only lighter with smaller droplets, and almost unique to the Galápagos. This water source provides good conditions for lush vegetation to grow.
On the leeward side of the islands, the side of the island facing away from the wind, the climate is drier, with much less rainfall. Once the wind has traveled to the top of the island and released its water, the wind traveling down the back side of the island has less and less water to release, which causes the drier climate on the windward side of the island. Because of the low amounts of precipitation on the leeward side of the islands, fewer plants can grow here.
Ocean currents also affect the weather and climate in the Galápagos Islands. There are two main currents, the Humboldt Current and Panama Current. From June to November, the Humboldt Current brings cold water from the southern hemisphere, causing what is known as the dry season in Galápagos. From January to June, the Panama Current carries warm water from the equator, resulting in a warmer, wetter season.
MATERIALS AND SETUP
- Virtual Galápagos Module Two Islands interactive website access
- Virtual Galápagos Fieldbook access for all worksheets and activities
LESSON SEQUENCE
ENGAGE
- Students can watch a video that transitions into Becki and Tomás looking for lunch/things they can eat on various islands.
- Students should do the Searching for Tortoise Food activity.
- Students make observations about each of the three major vegetation/climate zones in Galápagos (arid, scalesia, and pampa), with the goal of identifying the general types of plants available, their accessibility to tortoises, and the amount of available vegetation.
- Students can return to their current claims about the scientific mystery to revise the evidence and claims, in case they have gained insight into the question from this activity.
EXPLORE
- Students should now connect vegetation zones with the two types of tortoises (ones with saddleback-shaped shells, like Becki, and those like Tomás, with domed shells) and their preferred food sources.
- Students can do the Compare and Contrast activity, which includes the cartoon images of Becki and Tomás, as well as actual images of saddleback tortoises and domed shell tortoises.
- Students complete the Vegetation Zone Debate worksheet.
- This activity encourages students to connect the shapes of the shells with access to food sources, which in turn are dictated by vegetation zones.
- Students can return to their current claims about the scientific mystery to revise the evidence and claims, in case they have gained insight into the question from this activity.
EXPLAIN
- Students watch a short video explaining which vegetation zones will be the best for Becki and Tomás for finding food, and then posing the question about why islands have different vegetation zones in the Galápagos.
- Students watch a video that explains why several different climate zones exist in the Galápagos.
- Students watch an animated whiteboard video that explains seasons and their relationship to ocean currents in Galápagos.
- Students can return to their current claims about the scientific mystery to revise the evidence and claims, in case they have gained insight into the question from these videos.
ELABORATE
- Students can do the Galápagos Real Estate Activity, where they use a map of vegetation/climate zones in the archipelago to identify where Becki and where Tomás could live, and also to observe that larger islands have multiple vegetation zones, whereas smaller ones are arid only.
- This activity gets students to note that only the largest islands have humid zones, and the small ones have only arid zones.
- Worksheet title: Galápagos Real Estate Activity
EVALUATE
- Students can watch a video that urges students to update their observations and claims and explains where Becki and Tomás are going to live, asking them to do the Galápagos Island Size activity.
- Students complete the Galápagos Island Size worksheet.
- Students can watch a video that summarizes the content explored by the students in Module 2: Islands.
DIFFERENTIATION
- Grouping for all activities is flexible and up to the teacher’s discretion.
- Students can complete activities by drawing pictures to represent their thinking rather than writing.
- All field book activities can be accessed electronically or the teacher can print copies for students.
- Additionally, fieldbook worksheets can be edited by teachers and students for increased accessibility.
ASSESSMENT
- Students will complete the Galápagos Islands Size handout.
- This handout checks students' knowledge about the vegetation zones and which type of tortoise (with domed shells or saddleback-shaped shells) is better suited for which vegetation zone/ environment. Students should use different colors to show which island has the different vegetation zones and where on the islands the vegetation zones occur relative to wind direction, and taking into account island size. In addition, students will cut and paste Tomás and Becki on the island best suited for them. There are questions corresponding with the activity for students to convey their understanding of the concepts.
This unit was designed by Ashley Vescio and Shannon Jedreicich, and edited by Ava Wojtaszek and Sarah Jekel.
You can download the lesson plan here:
Virtual Galápagos
virtualgalapagos.colgate.edu
