Publication No. 10407
Stick Bug Survival
Student Laboratory Kit
Materials Included In Kit
Aluminum pans, 8
Toothpicks are sharp. Warn students to use good judgment when handling the toothpicks so that no one gets punctured with a toothpick.
All materials may be reused many times. Have students sort the toothpicks at the end of the activity so that they are immediately reusable in your next class.
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering PracticesDeveloping and using models
Planning and carrying out investigations
Analyzing and interpreting data
Using mathematics and computational thinking
Constructing explanations and designing solutions
Disciplinary Core IdeasMS-LS2.A: Interdependent Relationships in Ecosystems
MS-LS2.C: Ecosystem Dynamics, Functioning, and Resilience
MS-LS4.B: Natural Selection
HS-LS2.A: Interdependent Relationships in Ecosystems
HS-LS2.C: Ecosystem Dynamics, Functioning, and Resilience
HS-LS4.B: Natural Selection
Systems and system models
Structure and function
Stability and change
HS-LS2-2. Use mathematical representations to support and revise explanations based on evidence about factors affecting biodiversity and populations in ecosystems of different scales.
Student data will vary considerably from the sample provided here. In this sample data the number selected of each color is held constant for each generation to illustrate the calculations and possible trend resulting from consistent selection over generations.
Answers to Questions
Stick Bug Survival
Predator/prey relationships can influence the nature and size of a population over time. Organisms that are killed before they reproduce do not contribute genes to the next generation! What can killing of selected individuals from a population do to the makeup of that population over time? How do populations change over time?
A species is a group of similar organisms capable of reproducing viable offspring of their kind. Those individuals that are involved in the production of offspring have their unique genetic material passed on to the next generation. Those individuals that are unsuccessful at reproducing do not pass their genetic traits to the next generation and their unique set of genes dies with them. All of the collective genes of a given population are referred to as the population’s gene pool. Since there is usually an uneven rate of reproduction among individuals in a population, the nature of the gene pool tends to vary from one generation to the next. If conditions during a given time period are detrimental to certain types of individuals and if the conditions affect the ability of the individuals to reproduce, then the gene pool of the population will be altered and changed over time. If “selection” for or against certain individuals affects their ability to reproduce offspring, it is referred to as natural selection. Biologists study populations and gene pools over time and study the trends in the makeup of populations resulting from natural selection.
A = Ratio of individuals of each color that will reproduce for the next generation.
D = Actual number of a specific color to add to the forest for the next generation.
E = Total starting population for each generation (carrying capacity).
Forceps, plastic, 4
Toothpicks have pointed ends and can cause punctures and slivers in the skin epidermis. Handle all the toothpicks carefully during this activity.
Warning: Be careful during the feeding activity—the toothpicks and forceps are sharp.
Student Worksheet PDF