In the modern era, Lamarck is widely remembered for a theory of inheritance of acquired characteristics, called soft inheritance, Lamarckism or use/disuse theory.[5] However, his idea of soft inheritance was, perhaps, a reflection of the wisdom of the time accepted by many natural historians. Lamarck's contribution to evolutionary theory consisted of the first truly cohesive theory of evolution,[6] in which an alchemical complexifying force drove organisms up a ladder of complexity, and a second environmental force adapted them to local environments through use and disuse of characteristics, differentiating them from other organisms.
Jean baptist lamarck was the first person to propose the theory of evolution.he proposed that the acquired characters are passed to ts offsprings.this known as the inheritance of acquired characters.for example elongation of neck and forelimbs in giraffe.even though this theory was disproved,his contribution to biology was appreciate because it changed the beliefs of thepeopleof olden days that the earth have not undergone any changes.