Darwinism and Lamarckism are two different ideas about how species change over time.

Darwinism:

• It says that natural selection is the main reason for changes.
• Animals and plants that have helpful traits are more likely to live long enough to have babies.
• For example, giraffes with longer necks can reach food that others can’t, so they are more likely to survive and have babies.

Lamarckism:

• It says that traits an organism develops during its life can be passed to its children.
• For example, if a blacksmith has strong arms from working hard, he might pass that strength on to his kids, according to Lamarck.

In short, Darwinism is about how survival helps some traits get passed down through genetics, while Lamarckism talks about how changes in life can be passed on.