The value to society of the many fossil discoveries that have been found over the last century are many. From an educational standpoint, fossils are terrific ways to excite the interest of the young in science, history and archeology. When you have movies being made about archeologists like Raiders of the Lost Arc and dinosaurs become popular entertainment figures, that is a victory for how science has tapped a common fascination with the past. That fascination all began with the discovery of fossilized dinosaurs and other creatures from the past that give paleontologists the clues they need to create replicas of what these ancient monsters must have looked like.
But there is another value to the study of fossils that may be even more important that the educational value to young and old alike. As science carefully dates and documents every detail about each archeological dig they conduct, a record can be constructed that links together various fossil discoveries into a story of prehistoric life. That story may even inspire theories about the origins of life on this planet and those theories only drive archeologists on to find more fossils to continue to fill in the gaps in the fossil record that leave some of those theories unfinished.
Some comparison between ancient species and their modern counterparts are easy to make and the evolutionary conclusions you can make are evident and easy to validate. Fossil records of ancient ancestors of many species including horses, giraffes, apes and even man show that we have clearly changed over the centuries and adapted to our environments. Few would deny the changes within the species that are evident when we see ancient examples of our own species that has been validated by fossilized evidence and we compare those records to what we look like and how we live today.
What still eludes experts in the fields of archeology who are gifted at finding more clues about our origins in the fossil records are fossil examples of transitions from one species to the next. The famous transition from single celled creatures to fish and then from fish to mammals and on up into more complex creatures ending with mankind has yet to be discovered in any versions of the fossil record.
Evolution within the species and the similarity of species suggests that those steps occurred to the extent that the gaps could be “presumed” true while we wait for that one great fossil discovery to prove these final transitions. But presumption is not scientific and devoted students of the origins of life will just have to hold out and leave that part of the story in the theory category until the gaps in our record of the evolution of life can be demonstrated beyond question.