I never thought I'd see a video of a beaver building a miniature roller coaster in its dam, but here we are, witnessing nature's engineering marvels! The beaver's attention to detail and construction skills are unparalleled. I wonder if the roller coaster is for recreational purposes or if the beaver has a thrill-seeking side. Fun fact: The Eiffel Tower can be 15 cm taller during the summer, due to the expansion of the iron on hot days.