David Trexler was born in
Conrad, Montana from Clifford "Trex" Trexler (1908–1962) and Marion Kathryn Trexler (1912–2014, née Nehring), homesteaders in
Bynum, Montana. Still in the present day, the Trexlers are a well established five-generation family continuying the tradition of the rodeo and cowboy culture. In 1917, 5 year-old Marion Nehring (David Trexler's mother) found her first dinosaur bone close to the family's homestead property in Bynum. This event triggered her passion for rocks and fossils. Trexler's father married Marion Nehring in 1927 and ranched for a living until the
Great Depression led the Trexlers to find different jobs as sideline activities. During this difficult period, Clifford Marion Trexler, David Trexler's elder and only brother, was born in 1933. Among the side jobs led by David's parents was one that Clifford senior did for a
jeweler and
lapidarist, but the jewelry store went bankrupt in 1937. The same year, once unemployed, Clifford "Trex" Trexler decided to open a "rock shop" in
Great Falls, the "Trex Agate Shop", which he ran until his death in 1962. In 1965, Marion married John Brandvold (1937–2020) who in the early 1970s moved the Trex Agate Shop to Bynum. That shop and activity led young David Trexler to grow up among rocks and fossils, wandering in north-western Montana in search of fossils for sale being a common practice for him, In 1974 and onwards, after his graduation at high school, Trexler worked as a mechanic, machinist, welder, heavy equipment operator and truck driver, but he had to quit in 1985 because of a labour-related accident. In 1986 he decided to start studies of Biology and Mathematics at the University of Great Falls in
Great Falls, Montana (present-day
University of Providence). There, in 1990, he was granted
Summa Cum Laude with a Bachelor of Science (BS) in Biology, and the recognition of
secondary education ability. Immediately after that, Trexler continued his studies at the
University of Calgary, in Canada, where he obtained a Master of Science (MSc) in Vertebrate Paleontology in 1995. == The
Maiasaura discovery and the Montana Dinosaur Center ==