 Most that time believed Earth & all its forms of life were thousands of years old and that the way things were then is the way they always had been

 rich fossil record challenged traditional view  some hypothesized there must have been >1 creation  each ended with catastrophic even that killed all living things

 proposed Earth shaped by geological forces that took place over extremely long periods of time  Earth must be millions of yrs (not thousands)

 predicted the human population will grow faster than the space & food supplies needed to sustain it

 hypothesized that by selective use or disuse of organs, organisms acquired or lost certain traits during their lifetime  these traits could then be passed on to their offspring  over time this led to a change in species

 all organisms have innate tendency toward complexity and perfection  organisms could alter their size or shape by using their bodies in new ways  acquired characteristics could be inherited

 Principles of Geology  processes occurring now have shaped Earth’s geological features over long periods of time

 realized what Malthus said about humans, (if the human population continued to grow unchecked, sooner or later there would be insufficient living space & food for everyone), also applied to plants and animals