Final answer:
Lamarck was the scientist who first believed that acquired traits were inheritable.
Step-by-step explanation:
Lamarck was the scientist who first believed that acquired traits were inheritable. According to Lamarck's theory of inheritance of acquired characteristics, organisms could pass down traits that they acquired during their lifetime to their offspring. For example, if a giraffe consistently stretches its neck to reach taller trees, Lamarck proposed that over time, the giraffe's offspring would have longer necks as an inherited trait.
Learn more about Inheritance of acquired traits