JEANBAPTISTE LAMARCK LAMARCK FIRST HE LIVED INTRODUCED THE FROM 1744 TO REVOLUTIONARY 1829 NOTION OF SPECIES THE THEORY OF MUTABILITY IN INHERITANCE OF ACQUIRED CHARACTERISTICS WAS HIS MOST WELL KNOW THEORY HE SUGGESTED IN 1801 LAMARCK THOUGHT THAT SINCE SIMPLE ORGANISMS LIVE ALONGSIDE ADVANCED ORGANISMS THEN THEY MUST BE CONTINUALLY CREATED BY SPONTANEOUS GENERATION 1802