source:http://www.ucmp.berkeley.edu/history/lamarck.html
Lamarck was one of the first people to suggest that species could change and alter their physical composition and various other genetic traits over time to fit certain needs. He believed in the "discredited theory of heredity", which caused him to be poked fun at and mocked by other scientific minds of the time. However, he was praised for his work as a biologist in studying the invertebrates of insects and mollusks.
- If the environment changes, the traits that are helpful or adaptive to that environment will be
different
Lamarck totally influenced this thought process, and was one of the first people to discuss this concept in regards to species and evolution. This idea certainly influenced Darwin, as Lamarck wrote of "many of the same lines of evidence that Darwin was to use in the Origin of Species" . Lamarck was a revolutionary thinker for his time, and Darwin certainly must have been influenced by such a outrageous thinker.
I'm sure Darwin could have come to his evolutionary theory without Lamarck, though it certainly would have been far more difficult and perhaps a slightly different theory had Lamarck not existed. Lamarck's theory of adaptive change is the core of Darwin's beliefs, and I find it hard to believe that Darwin was not significantly influenced by Lamarck's prior work.
The attitude of the church was quite skeptical of Darwin's book On the Origin of Species, and it caused him to publish several editions of the book to respond to the various arguments posed by religious-inspired writers. Darwin actually included mention of "the creator" in his book, and appeared to still believe in God at the time, which suggested that he believed in some sort of evolutionary/God hybrid theory.
