An honest question here, but does anyone know WHEN BYU started to include evolution in their biology? Was this at the same time most (western) universities started teaching it? Was it about at the same time most private/religious institutions started to include it?
I think a fair question could be the ages of those questioned. If you were to ask many older BYU grads about evolution (who may not have taken courses on evolution), they might give you a different answer than those who just barely graduated and took a course (which as Colton pointed out, is required for all students).
I know for me that my knowledge on evolution would be a lot more limited than what it already is had I never taken the required Biology classes that I did.
WARNING: Mini-essay/rambling forthcoming:
Mormons believe in evolution. Mormons believe man can evolve into a God. If the jackass down the street from me can evolve to a god then I see no reason to dismiss the evidence or theory that we evolved from a gorilla/chimp like ancestor.
It was never prohibited and thus there doesn't appear to be a date that it was actually permitted:
https://theboard.byu.edu/questions/49978/ It was taught as early as 1910; however, there were two professors fired during that period. Some claim they were fired due to teaching evolution, while others argue they were fired for other reasons. (This was also under the eyes of Joseph F. Smith, father of Joseph Fielding Smith, who I mention below).
https://signaturebookslibrary.org/?p=11583 (ctrl+f evolution and go from there). Pretty much, the older leaders during this period were more okay with the teaching of evolution than the younger church leaders (J. Reuben Clark, Joseph Fielding Smith, et al. were not that cool with the "secularism") so as the years progressed, the pressure to avoid teaching the topic also increased as the older leaders died off.
Keep in mind, this was 10-15 years prior the the infamous Scopes Monkey Trial. So, BYU was not unique in its efforts in trying to figure out how to fit evolution into their teachings, especially for a church school wary of creeping secularism. The 20s-70s were a period of intense struggle by the church in attempting to shift from a western, largely mysterious, sect into mainstream US culture and religious thought. This led to a lot of internal struggles about how to make doctrine fit shifting cultural views (Word of Wisdom and Alcohol - prohibition era is when the church finally banned beer; blacks and the priesthood; evolution; age of the earth; etc.).
Even today some parents and students still confront some BYU Idaho professors about their teaching of the subject, but it's one of those beliefs that many conservative Mormons likely hold, but they aren't very vocal about it:
https://www2.byui.edu/Perspective/v4n2pdf/v4n2_firestone.pdf I've also heard that some donors threatened to withhold funds due to a Darwin Week at BYU a few years ago. Colton, have you heard anything like that from any Biology professors?
Let's not kid, a lot of Mormons vehemently opposed evolution and were strong proponents of a young earth theory - including, most notably, Joseph Fielding Smith (father-in-law to Bruce R. McConkie - McConkie has had a huge impact on Mormon doctrine/thought. His ideas have also been very embarrassing for some portions of the membership. He was also very critical of evolution and anyone who believed it). For those unfamiliar with Joseph Fielding Smith, he served as Church Historian, was the son of the 6th prophet of the church who officially ended polygamy, grandson of Hyrum Smith (Assistant President of the Church to, and brother of, Joseph Smith), eventually became prophet himself from 1970-1972, and was a PROLIFIC writer and producer of doctrine and theology. He'll also probably be the last prophet to be so outspoken on points of doctrine as well due to the current politics and political correctness of the church. His writings were very influential on Mormon thought and doctrine to this day. Anyways...
So up until 1972, the Mormon church had in Joseph Fielding Smith a prophet who was a young earth creationist and outspoken critic of evolution. So it's not surprising that a lot of Mormons still do not believe in evolution, maybe just because of Joseph Fielding Smith and some of his writings. And even if they think evolution makes sense, etc., the statements by someone such as Joseph Fielding Smith could still likely influence their feelings on the topic and effect their responses to poll questions like the Pew Center's.
Additionally, the creation story is a bit more complex for Mormons which is what I think Colton somewhat hinted at. The creation plays a major role in Mormon theology and is a focal point of the Mormon temple experience. It's also not as simple/black and white for a Mormon to answer "do you believe in 'evolution' or 'creationism?'" Many Mormons believe Adam was literally the son of God. Others believe that God used evolution to create Adam. Others believe in "pre-adamites" (seriously, google this if you haven't heard of it and enjoy Mormon doctrine - it's some very unique theology! This was also the basis of major public disagreement between Joseph Fielding Smith and James Talmage (another super influential Mormon theologian)). Some even believe Adam and Eve were living on another earth prior to this earth and God brought them down here and they went from being an immortal being to a mortal being by eating the forbidden fruit.
Also, there's the whole BYU Evolution Packet thing in case anyone's interested. It seems to have been given to professors at BYU regarding the doctrine and how to teach the subject etc. (Just google "BYU Evolution Packet" if you want a compilation of Mormon teachings).
Conclusion: Basically, whereas church leaders used to be quite outspoken on issues of doctrine, the church now prefers to obfuscate past teachings, downplay the relevance of the non-mainstream theories, and try to avoid any controversial stances. Well, except for the gays. No matter what you think about Mormonism, it has a very interesting development of theology and doctrine.
tl;dr - There isn't a specific date that BYU professors started teaching evolution because the topic was never really banned - it was definitely taught as early as 1911. However, as the years passed, the leaders actually became more critical of the teaching. And Mormon theology pretty much believes man was placed here already in the human form so evolution was somewhat unnecessary, but men may evolve into a god.
