Every year, Nikon's Small World in Motion Competition rounds up the best microscopic videos from scientists across the world. The winners of the 2012 competition have just been announced, and the results are strange but beautiful.
The video above, filmed by Dr Olena Kamenyeva from the National Institute of Health, took first place. It shows the immune response in the lymph node of a mouse, when it was activated by a laser -- and it's deeply mesmerising.
The other entries are worth a watch too. Dr Stefan Lüpold, from Syracuse University, scooped second place with this video. It shows sperm from two different males (green and red) competing within the reproductive tract of a female fruit fly. Eye-opening.
Third place was taken by Dr Nils Lindström from the University of Edinburgh with this time-lapse, which reveals how the kidney cells of mice develop over the course of four days.
Finally, our favourite runner-up was filmed by Dr Oleg D. Lavrentovich from Kent State University. It shows the amazing fluid dynamics of liquid crystals: the changing colours are a result of shifts in the molecular orientation of the flowing liquid. Beautiful.