Color Vision Genetics Evolution Simulation

Contributor
California Academy of Sciences
Type Category
Instructional Materials
Types
Activity , Simulation
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

In this activity, students will simulate how genes on chromosomes are passed from generation to generation while exploring color vision and its genetic history in humans and other primates. Students will explore the sex-linked trait of color vision and how it affects males and females in different proportions by the flipping of pennies to simulate chance. The lesson introduces selective pressures, in the form of attributes of the physical environment, that will selectively kill off certain members of the population that are then replaced by the surviving offspring, and gradually change the gene pool.

Intended Audience

Learner
Educational Level
  • High School
  • Middle School
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

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.

Clarification Statement: Emphasis is on using simple probability statements and proportional reasoning to construct explanations.

Assessment Boundary: none

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
This lesson may be used as a follow-up activities on basic genetics and serve as a bridge to connect genetic variation and natural selection as mentioned above. Students will model natural selection by participating in a simulation using probability and selective pressure. A slide presentation not only helps facilitate the activity, it also provides environmental conditions as a model of selective pressure. The students are given the answers during the simulation however the teacher should have students come up with explanations for why the populations change over time due to selective pressure and then arguing their explanations with the class. This can be accomplished using the Claim, Evidence, and Reasoning (CER) format. Here is a link to a NSTA Webinar slide presentation on using CER: http://learningcenter.nsta.org/products/symposia_seminars/nsta/files/howdoyouknowthat--helpingstudentswriteaboutclaimsandevidence_12-12-2012.pdf. Students can research some of the reasons for the evolution of 3 color vision and construct explanations for why it would be a selective advantage for an individual to have it.

MS-LS3-2 Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.

Clarification Statement: Emphasis is on using models such as Punnett squares, diagrams, and simulations to describe the cause and effect relationship of gene transmission from parent(s) to offspring and resulting genetic variation.

Assessment Boundary: none

This resource appears to be designed to build towards this performance expectation, though the resource developer has not explicitly stated so.

Comments about Including the Performance Expectation
This activity can be used as a culminating activity after you have introduced sexual reproduction. It can serve as formative assessment to identify any areas that require additional clarification on variation in sexual reproduction. As a bridge between the genetics and natural selection it would be appropriate to have students come up with explanations for why the populations change over time and then arguing their explanations with the class. They can research some of the reasons for the evolution of 3 color vision and construct explanations for why it would be a selective advantage for an individual to have it.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
This simulation allows students to model the processes of meiosis and fertilization as they investigate the inheritance of the sex-linked trait of color vision. This modeling allows them to use their understanding of concepts to see a direct relationship between the chromosomes from each parent and the resulting variety of traits. Whole class discussions need to include comparisons of the different genotypes and the resulting variations in color vision. Think-Pair-Share can be used to examine the trends seen in the data charts created from each generation of offsprings. A “Gallery Walk” will help extend the discussion from pairs to groups analysis of the trends. The facilitator, through the Socratic questioning technique, should examine the shifts from 2-color vision to 3-color vision in terms of natural selection. Or have students develop their explanations and argue them with their peers. Questions are provided to facilitate these discussions within the “slide presentation”.

Disciplinary Core Ideas

This resource appears to be designed to build towards this disciplinary core idea, though the resource developer has not explicitly stated so.

Comments about Including the Disciplinary Core Idea
This simulation uses random sets of 6 combinations of the sex-linked traits of color vision to represent 2-color and 3-color vision. Through the modeling, students are able to chart the variety that results from generation to generation. The questions provided probe the resulting changes and help the student discover how sex-linked traits affect male and females in different proportions.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
This resource helps students see a definite relationship between sex-linked traits and how they affect males and females in different proportions. For example, students see through the use of the model that since females (XX) have two X chromosomes, there are two chances to get a working copy of a gene. Males (XY) have only one X and so only have one chance for a working copy. Males, therefore have a much higher incidence of color blindness than females. The relationship between genetic variation and environmental conditions are also explored within this model by showing that individuals that are better adapted to their environment are more likely to survive and therefore reproduce.

Resource Quality

  • Alignment to the Dimensions of the NGSS: There is a strong correlation between the three dimensions of NGSS. However, the resource only addresses sexual reproduction not asexual reproduction, with a total alignment of the fact that sexual reproduction provides variety. This lesson provides an opportunity for hands-on exploration of the performance expectation and the crosscutting concept of patterns, which can be used to describe cause and effect relationship. However to increase student involvement students should develop their own explanations and argue them with their peers.Grade‐appropriate elements of the science and engineering practice, disciplinary core idea, and crosscutting concept, work together to support students in three‐dimensional learning.

  • Instructional Supports: The activity engages students in the practices that work together with disciplinary core ideas and crosscutting concepts to support students in making sense of genetic variation in sexual reproduction. The resource provides guidance in facilitating the lesson with a “slide presentation, “scientific terms”, “educator background, and links to extensions. Though working with a partner and explaining their thinking when responding to questions provided, students have multiple opportunities to express and clarify their ideas. This activity should be thought of as a cumulative lesson or can be used as part of a Project Based Unit.

  • Monitoring Student Progress: Formative assessments of three-dimensional learning are embedded throughout the instruction. First of all, as they create the offspring and secondly as they observe in the slide presentation the selective pressure scenarios that allow the students to practice their understanding of 2 and 3 color vision. Extensions and enrichment to the basic lesson are provided to extend the learning.

  • Quality of Technological Interactivity: - none -