Age Structure

Juveniles, adults and the growth factor

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Stage-structured models track juveniles and adults separately (Leslie matrices).
• The population settles into a stable mix, growing by a factor λ each year.
• λ = 1 means each adult exactly replaces itself; sensitivity analysis shows which survival rate matters most.

Steps

1. One year on
2. Stages and matrices
3. Hold it steady
4. The growth factor
5. Which number matters most?
6. Tenfold growth