Genes and Traits

What You'll Learn

Natural selection is the process where organisms with traits better suited to their environment survive and reproduce more successfully. Over time, this drives evolution.

Key Words

DNA
gene
chromosome

Materials Needed

slides
onion skin
iodine stain
paper

Safety First

Handle glass items carefully to avoid breakage.
Do not mix unknown chemicals together.

Steps

Step 1 — Read

Review the background information on Heredity before starting.

Step 2 — Do

Survey your class for a genetic trait (attached vs. free earlobes, tongue rolling, hitchhiker's thumb). Create a bar graph of the results.

Step 3 — Observe

Look for patterns in your observations.

Step 4 — Record

Make a graph or chart showing your results.

Check Your Understanding

Question 1

1 of 3

What is natural selection?