Human Impacts on Earth’s Systems
Lesson 3: Species Interactions: Pollination
Overview:
No organism exists by itself but instead lives in a complex web of interactions that also depend on the environmental conditions of where the organism lives. Utilizing student’s prior understanding of species relationships, this activity works towards developing an understanding of organism interactions in the physical environment to obtain matter and energy. To achieve this goal students will be asked to call on prior knowledge and evidence-based explanations to understand that populations of organisms are dependent on their environmental interactions both with other organisms and abiotic factors. Species’ relationships are an important factor in determining if an organism can live somewhere or not.
Objectives:
- Students will be able to predict patterns of interactions among organisms across ecosystems.(MS- LS2-2).
- Students will be able to understand that predatory interactions may reduce the number of organisms or eliminate whole populations of organisms. Mutually beneficial interactions may become so interdependent that each organism requires the other for survival (MS-LS2-2).
- Students will be able to construct an explanation and design solutions regarding the idea that changes in biodiversity can influence humans’ resources, such as food, energy, and medicines, as well as ecosystem services that humans rely on for survival- for example, water purification and recycling. (MS-LS4.D).
Vocabulary:
Biodiversity, mutualism, symbiotic interactions
Make ahead:
Prepare a device to display a short video and PowerPoint
Whiteboard or a similar tool to display class responses
Print Worksheet
Prepare moth role-play props
Captivate & Collaborate:
Teacher Says/Does | Open Questions | Student Answers |
Warm Up: 1. Ask students to pair up with a classmate, collectively write out a list of five things that they depend on to survive and be prepared to share with the class. After adequate wait time, call on students to share their list out loud. The teacher will record and list the students’ answers on the board. Once the list is written, point out answers that are not really necessary for survival. | 1. Create a list of things they (students) depend on to survive. | 1. -air -iPhone -pets -friends -clothes -family members -food -water -sunlight -gut bacteria -mitochondria |
2.Then, review the list and ask students which of these things also depends on them to survive (dependent relationship). It is likely that few items on the list really need us for survival, and most things on the list are not dependent on the student for survival. | 2.What do we really need to survive? Which of these things also depends on us to survive? | 2. We need air, water and sunlight to live. None of the items in the list above also depend on us for survival. |
Explain to students that there are four main types of species interactions: mutualism, commensalism, competition, parasitism, and predation. Today our focus will be on mutualistic species interactions. When two organisms of different species each benefit from their interactions with each other we call this a mutualistic relationship. This type of interaction exists on a spectrum from helpful to destructive within the same species interaction. For example, something could be beneficial in some conditions, and parasitic in other conditions. As a class, work to brainstorm species that do depend on each other for survival (co-dependent, meaning both species depend on each other to survive). Explain to students that mutualism is a kind of symbiosis that can be codependent. For example, there are many types of bacteria that live in our bodies, specifically our intestines. We have a mutualistic relationship with these bacteria because they help us to digest our food and they get food in the process. (see PowerPoint for pictures) Show National Geographic videos (or have assigned this the night before for homework) on species interactions 3.Create a list on the board of species that are mutually dependent on each other with student help starting with some of the examples you have shown. | 3.Can you think of any examples of species that are mutually dependent on each other? 3A.What are pollinators that you know of? After some wait time, show pictures. | 3. EX: Humans and.. Gut bacteria, mitochondria 3A. EX: In some cases, pollinators and plants are an example of a symbiotic interaction. For instance, the fig wasp and fig are co-dependent. |
Describe:
Teacher Says/Does | Open Questions | Student Answers |
One of the most fascinating species interactions is the relationship between the yucca moth and the Joshua tree. Usually, when plants are pollinated by pollinators, for example, bees, it is by accident. When bees travel from one flower to the next, the bee is accidentally spreading its pollen. Joshua trees and yucca moths have one of the most amazing pollination stories in biology (described in following activity). Also, see PowerPoint for images and video. | *Prepare Moth Role Play Activity | |
4. Give students the moth pollination worksheet and then do the moth pollination role play activity (see supplementary section). | 4. Moth Role Play Activity and Props in Supplementary Section | |
Joshua trees are completely dependent on these moths. Without the yucca moth, there is no other way that the Joshua tree can be pollinated. Please see moth role play activity and discuss activity as you read the following passage. Have students help act out the story as you explain it. This tiny moth (size of an apple seed) purposefully collects pollen from the Joshua tree flower so she can pack it into the flower's stigma. The yucca moth pushed the pollen down into the stigma and then lays her eggs inside of the stigma. As time passes, young moth larvae hatch and develop in the security of the Joshua tree flower that is now growing into a seed pod with hundreds of seeds. The moth and her larvae will eventually eat some of the seeds within the developing seed pod, chew a hole through the pod and fall to the desert sand where they build their cocoon in the soil. | ||
After a year, the moth larvae cocoon opens underground, and the new Yucca moth emerges from the desert sands and enters the world! It flies back up and pollinates the Joshua tree again. This beautifully codependent relationship between the Yucca moth and the Joshua tree has evolved over many hundreds of thousands of years. It is called coevolution! 5. Ask students to think about these questions as the class moves into the final activity. | 5.How do you think the changing climate is going to affect the moth, larvae, and flower itself? What if the moths come out earlier than usual and there are no flowers? What happens if the moth lays too many eggs? As mentioned above, this is where it becomes parasitic. |
Investigate:
Teacher Says/Does | Open Questions | Student Answers |
Assignment Wrap Up-- (Teacher has two options for student assignments): Option 1: In summary, students will write a journal entry from the viewpoint of a moth. In the journal entry, students will pretend that they are a yucca moth living in a world where the climate is quickly changing. How does the Joshua tree/moth interaction change? | Ask students to list environmental changes that would occur as the climate quickly changes. Record the students' answers as a list on the board so that students can refer to it as they create their journal entry. Ask your class if there is anyone that would like to share their journal entry. | Temperature rising, pollution (greenhouse gases), less rainfall |
Option 2: Ask students to choose one climate change scenario and create a journal entry in which they discuss how climate change could affect their lives, while carefully considering the discussions throughout the week (see previous lesson plans). Encourage students to draw a picture and/or a diagram to illustrate the story they are telling in their journal. | Ask students to list environmental changes that would occur as the climate quickly changes. Record the students' answers as a list on the board so that students can refer to it as they create their journal entry. Ask your class if there is anyone that would like to share their journal entry. | Temperature rising, pollution (greenhouse gases), less rainfall |
Supplementary Materials:
Stop motion animation: https://www.youtube.com/watch?v=sB0Hejnxjs0
Example of Symbiotic Relationship Videos
- Ant and Butterfly Symbiosis
- https://video.nationalgeographic.com/video/ant_caterpillarsymbiosis
- Clownfish and Sea Anemone
- https://video.nationalgeographic.com/video/clownfish_amonganemones
- Acacia Tree Ants
- https://video.nationalgeographic.com/video/ant_acaciatree
Moth and Pollination worksheet and role-play → Joshua Tree Moth Role-Play & Props
https://docs.google.com/document/d/1lsYfK1QNJxpXzRG5yEcyZp7E-xqm2J0qYk9F_PbAKjA/edit?usp=sharing
PowerPoint “Lesson 3 - species interactions” with Images →
https://docs.google.com/presentation/d/1Zs3hh7ci_7Y8zoeB1wi36qv4-2ZfuXrbCbMiFJeHFQE/edit?usp=sharing