Some ways in which Brian's past science lessons come in handy include:
Understanding the importance of fire: Brian remembers from his science classes that fire can provide warmth, light, and a means to cook food. He uses this knowledge to start a fire and keep it going, which helps him stay warm and cook food.
Knowledge of animal behavior: Brian recalls learning about animal behavior in science class, and he uses this knowledge to observe and understand the animals around him. For example, he learns to watch for the behavior of birds to determine if a predator is nearby.
Understanding plant life: Brian's knowledge of plants helps him identify edible berries and plants, as well as plants that are poisonous.
Basic physics: Brian's understanding of basic physics helps him build tools and structures that are useful for survival. For example, he uses the principle of leverage to build a shelter and create a bow for hunting.