Look Who's Coming to Dinner: Selection by Predation

HHMI Keri Shingleton, PhD Sandra Blumenrath, PhD
Type Category
Instructional Materials
Case Study , Activity , Answer Key
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.



This HHMI Biointeractive activity is designed to supplement/support the film, The Origin of Species: Lizards in an Evolutionary Tree.  The resources is based on real measurements from a year-long field study on predation, in which Dr. Jonathan Losos and colleagues introduced a large predator lizard to small islands that were inhabited by Anolis sagrei.  The activity is written in a case-study format, in which students are asked to formulate a hypothesis and analyze a set of sample research data from actual field experiments designed to test this hypothesis.  The activity illustrates the role of predation as an agent of natural selection. It emphasizes that strong selective pressure can have measurable effects on trait variations in a population within a short time. It also shows that natural selection can change direction in just a single generation.

Intended Audience

Educational Level
  • Middle School
Access Restrictions

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

Performance Expectations

MS-LS4-6 Use mathematical representations to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time.

Clarification Statement: Emphasis is on using mathematical models, probability statements, and proportional reasoning to support explanations of trends in changes to populations over time.

Assessment Boundary: Assessment does not include Hardy Weinberg calculations.

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
The activity guides students as they analyze authentic research data related to anole lizard populations on various islands. Mathematical representations (graphs, calculations) help students make sense of the relationship between predation and the distribution of traits within a population. As currently written, this activity aligns to the middle grade (6-8) band performance expectation. The resource indicates it was designed for the high school/college level. In order to fully address the high school grade band, the resource would need to more closely align with the 9-12 elements of the disciplinary core idea (LS4. C Adaptation). Additional modifications might include students comparing various data-sets to identify consistencies, make qualitative and/or quantitative claims regarding the relationships between independent and dependent variables, or develop a directional hypothesis that specify what happens to a dependent variable when an independent variable is manipulated.

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 resource engages students in actively analyzing and interpreting data to make sense of the changes in the anole populations. As currently written, the activity heavily guides the students through the process of analysis. Given the students’ mathematical abilities and level of mastery of this SEP, teachers may want to remove some of these scaffolds. Additionally, teachers may want to revise the accompanying resources to allow for more student-generated questioning. This resource naturally pairs with elements of many other science and engineering practices (e.g. constructing explanations, using mathematical computations, and engaging in argumentation). Consequently, teachers can use this resource in a multitude of ways to strengthen student mastery of various science and engineering practices. While the resource explicitly aligns to the performance expectation, teachers should not assume that this one activity will lead to mastery of all three dimensions and should embed this into a longer learning sequence.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
This resource provides a single example of trait distribution changing over time as a result of natural selection. For students to fully master this concept, they will need to engage in additional learning opportunities. Additionally, this resource provides evidence that changes in populations can occur over a relatively short time span. Teachers will want to be sure that students do not develop misconceptions that this is always the case in natural selection. Consequently, teachers may want to use additional data sets to provide evidence that trait distribution can change at varying rates. The data set does not provide direct evidence of differential survival and reproduction in the anole population, but the analysis questions do ask students to make predictions about survival and reproduction.

Crosscutting Concepts

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

Comments about Including the Crosscutting Concept
This resource is framed around students using patterns in the provided data to make sense of the cause and effect relationship between natural selection (predation) and trait distribution within a population. The accompanying resources rely heavily on the teacher guiding the student, through specific questioning, to make these connections. Given the level of the students and their degree of mastery of this crosscutting concept, teachers may want to revise the resources to give students more opportunities to generate their own questions and make their own connections using this CCC lens.

Resource Quality

  • Alignment to the Dimensions of the NGSS: Look Who’s Coming to Dinner: Selection by Predation engage students in three-dimensional learning as they seek to make sense of the phenomenon of trait distribution in a population over time. This resource drives student learning by making available authentic data that students can analyze to answer questions and support claims. The resource is highly scaffolded, and some of this scaffolding might be removed based on students’ level of mastery of the relevant dimensions.

  • Instructional Supports: By using authentic data from a primary source, this resource provides an excellent, scientifically accurate context in which students can engage in three-dimensional learning to make sense of a phenomenon. The background information and the discussion questions in the Educator Materials are excellent and provide guidance for teachers to support instruction. However, these suggestions do not explicitly address how teachers could incorporate additional elements of practices or make the crosscutting concepts more explicit for student use.

  • Monitoring Student Progress: As currently written, this resource does provide an opportunity for teachers to monitor student progress. With modifications, this resource offers an excellent opportunity to gather evidence of students’ three-dimensional learning (e.g. written arguments, written explanations, student discussions).

  • Quality of Technological Interactivity: - none -