The progression of the mammillothalamic axonal tract, from its formation to the mature structure. The mammillothalamic tract is the collection of axons that connects the two major subdivisions of the diencephalon (hypothalamus and thalamus) and closes the diencephalic circuit. [ GOC:dph http://www.ncbi.nlm.nih.gov/pubmed/10662642 GOC:yaf ]