The focus of this series of lessons is natural selection, but the concept is presented through the lens of presenting arguments to dispel common misconceptions about natural selection.
Begin the lesson by having students record their ideas (quickwrite) in Google Classroom about:
2. Survival of the fittest
3. Evolutionary purpose
Explain to students that they will be presented with the following three common misconceptions about natural selection in a short video:
1. Evolution is organisms adapting to their environment (an individual does not adapt-a species adapts)
2. Survival of the fittest (it is not the strongest or healthiest that survives, it is the individual who is most"fit" for a specific environment)
3. Evolutionary Purpose (there is no predetermined plan that progresses toward an ideal form)
Show Myths and Misconceptions Video from Ted-Ed during which students should listen for an explanation of each of these concepts, and define/explain them on their Google doc.
During the upcoming series of lessons, students will gather and record evidence about natural selection to dispel the misconceptions.
2 Direct Instruction
CK-12:Life Science-Biology: Natural Selection requires a free sign in and contains detailed and informative videos, readings, interactive games and review questions. All or some of the resources on this site may be used to teach the concept of natural selection depending on your student population and time constraints.
I really like the Real World Application videos as they make the concepts and content relevant to kids.
Below is how I use the resources for this lesson:
1. Students use the interactive Links: Natural Selection: White and Brown Mice and Natural Selection: Natural Disasters to explore the idea that camouflage is a key aspect of survival and if the environment changes, the population will change because the camouflage is no longer effective. They record their observations and analysis in Google Classroom.
2. Students explore the Readings-Natural Selection. These consist of several different articles explaining the concept of natural selection, at various reading levels that can be used to differentiate instruction.
3. Give the Practice and/or Quiz as a check for understanding
Students use Google Classroom to record evidence that could support or dispel misconceptions
3 Guided Practice
Students will learn more about how traits make an animal "fit" for a specific environment and what happens if the environment changes by playing, "Who Wants to Live a Million Years?"
Students choose traits with the goal of creating a population of organisms that will live a million years, even if the environment changes. I really like the fact that even if students are successful and their organisms survive a million years, the environmental changes occur randomly so in the next round, those traits will most likely NOT be successful.
The game reinforces two concepts:
-populations adapt, not individual organisms
-traits that make an organisms "fit" or successful in one environment, do not ensure success in another environment.
Student record their observations and reasoning in Google Classroom.
4 Independent Practice
In the previous activity, students worked with imaginary critters, selecting traits they thought would be most advantageous to survival.
Remind students of the three misconceptions for which they are gathering evidence in order to dispel. In this activity students will be looking for specific evidence regarding each misconception.
The PhET Simulation: Natural Selection, requires Java. In this simulation, students further explore natural selection by controlling the environment and observing mutations in bunnies. The goal is to create a stable population, not one that dies out or one that takes over the world! Students have control of the variables of environment, predators and food. They can pause the game and see graphs of the previous generations of rabbits.
There are several teacher-created worksheets on the site, published in Word. I find one that most closely aligns with my goals for a particular class and modify it to guide students through the activity.
Additionally, students should look for evidence from this simulation that provides arguments against the misconceptions presented in the Hook.
One of the features I like in this simulation is the bunny reproduction can be paused and the genotypes and pedigrees can be observed. For students who already have a background in genetics and patterns of inheritance, this information can be analyzed as students make connections between genetics and evolution.
Upon completing the simulation, students use Google classroom to revisit the three misconceptions introduced in the Hook. Encourage students to think about how their ideas have changed from the original quickwrite. Students create arguments supported with evidence from the PhET activity as to why each statement is a misconception.
Misconceptions and key concepts to be addressed:
1. Evolution is organisms adapting to their environment.
Students should recognize that when the environment changed, the bunnies did not change color. The ones that were not camouflaged died and the rabbits with mutations survived to reproduce, thereby increasing in number; hence the population changed.
2. Survival of the fittest
Students should recognize that "fitness" does not refer to size or strength but how fit the bunny is to survive in the particular environment, arctic or equatorial.
3. Evolutionary Purpose
Students should recognize there is no predetermined "ideal bunny". The appearance or phenotypes of the bunnies depend on random mutations and/or the environment.
On the Ck-12 Biology: Natural Selection Website, there are 33 examples (linked above) in a variety of formats (videos, articles games, etc) of Real-World examples of natural selection. They can be filtered according to grade level. If students are interested in extending their learning or looking for examples of modern-day evolution, this site has it.
Key Standards Supported
|WHST.6-8: Text Types and Purposes|
|WHST.6-8.1||Write arguments focused on discipline-specific content.|
|WHST.6-8.1a||Introduce claim(s) about a topic or issue, acknowledge and distinguish the claim(s) from alternate or opposing claims, and organize the reasons and evidence logically.|
|WHST.6-8.1b||Support claim(s) with logical reasoning and relevant, accurate data and evidence that demonstrate an understanding of the topic or text, using credible sources.|
|WHST.6-8.1c||Use words, phrases, and clauses to create cohesion and clarify the relationships among claim(s), counterclaims, reasons, and evidence.|
|WHST.6-8.1d||Establish and maintain a formal style.|
|WHST.6-8.1e||Provide a concluding statement or section that follows from and supports the argument presented.|
|WHST.9-10: Text Types and Purposes|
|WHST.9-10.1||Write arguments focused on discipline-specific content.|
|WHST.9-10.1a||Introduce precise claim(s), distinguish the claim(s) from alternate or opposing claims, and create an organization that establishes clear relationships among the claim(s), counterclaims, reasons, and evidence.|
|WHST.9-10.1b||Develop claim(s) and counterclaims fairly, supplying data and evidence for each while pointing out the strengths and limitations of both claim(s) and counterclaims in a discipline-appropriate form and in a manner that anticipates the audience’s knowledge level and concerns.|
|WHST.9-10.1c||Use words, phrases, and clauses to link the major sections of the text, create cohesion, and clarify the relationships between claim(s) and reasons, between reasons and evidence, and between claim(s) and counterclaims.|
|WHST.9-10.1d||Establish and maintain a formal style and objective tone while attending to the norms and conventions of the discipline in which they are writing.|
|WHST.9-10.1e||Provide a concluding statement or section that follows from or supports the argument presented.|
Key Standards Supported
Biological Evolution: Unity and Diversity
|MS-LS4-4||Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment.|
|HS-LS4-2||Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.|
|HS-LS4-4||Construct an explanation based on evidence for how natural selection leads to adaptation of populations.|
|HS-LS4-5||Evaluate the evidence supporting claims that changes in environmental conditions may result in: (1) increases in the number of individuals of some species, (2) the emergence of new species over time, and (3) the extinction of other species.|