What kind of animals did jean-baptiste lamarck study?

Jean-Baptiste Lamarck primarily studied invertebrates, particularly focusing on animals such as mollusks and worms. He also made significant contributions to the classification and understanding of various groups of animals, including amphibians and reptiles. His work laid foundational concepts in Biology, particularly regarding evolution and the adaptation of species. Lamarck is best known for his early theories on evolution, emphasizing the role of environmental factors in shaping the characteristics of organisms.