I did a search on different animal's feet and it was good. It took a while before I finished the whole paper. I learned a lot information about them.
Alien deep: revealing the mysterious living world at the bottom of the ocean by Bradley Hague — This book was about life on the ocean floor. There are some strange animals that live near these ocean vents that somehow create hospitable environments for life. If you're interested in space exploration, this is an interesting parallel.