On the FileMaker Pro 16 Technical Specifications it says that FileMaker Pro 16 is compatible with Mac OS X El Capitan 10.11 and macOS Sierra 10.12. On the FileMaker 16 Deprecated and Removed features page it only mentions removal of support for OS X 10.9 Mavericks. I tried installing on OS X 10.10 and it refuses. The removal of support for OS X 10.10 should be mentioned in the "removed features" section of the Deprecated Features page.
JEDtech:
Thank you for your post and pointing out the omission.
Knowledge Base Article #16005 has been updated to now show OS X 10.10 Yosemite in the "removed" section.
TSGal
FileMaker, Inc.