The Sex Lives of Christmas Trees (Safe for Work!)
Pine trees make more pine trees via sexual reproduction—they just do it with male and female pine cones. And they've been at it for a long time, long before flowering plants came onto the scene. In this beautiful 4K video from KQED, we learn about how conifers reproduce, the role of the wind, and we see beautiful footage of the whole thing. Make this one fullscreen!
Also relevant is this timelapse video showing a female pine cone opening over the course of 24 hours. Behold!