The winner of the Nikon Small World in Motion contest has captured a tiny animal called coral polyp as light levels go down and it emerges. Polyps are crucial builders of coral reefs. The video shows the green tissue of a staghorn coral polyp (Acropora muricata) and the photosynthetic algae that live in symbiosis inside the coral, seen in bright purple.
Coral reefs support an incredible array of marine life; they provide a home to about 800 hard coral species and over 4,000 species of fish, which can be as much as 25 percent of ocean life, depending on the reef. They are considered to be some of the most critical and valuable ecosystems on the planet. Coral reefs are also under pressure, many have been destroyed or are under threat from pollution or climate change.
To create the video, Philippe Laissue, the Director of the Bioimaging Facility at the University of Essex, had to build a light-sheet microscope, which can capture fluorescent images rapidly and enables the visualization of larger, living specimens. Laissue's scope imaged the polyps emerging.
"Dimming the light has enabled me to show the coral's dynamics close up, and illustrate the beauty and otherworldliness of these ancient organisms," said Laissue. "At the same time, we can collect important information about what is happening on the cellular level when corals react to different environmental conditions. This helps us to better understand corals and their development, thus contributing to finding the best strategies to protect and conserve them."
Above, the second-place video shows parasites called Vampyrophrya swimming around inside their host, a copepod. Below, the third-place video captured a microbe called Stylonychia using its cilia and generating a vortex, which helps it gather food. Other videos that were runners up can be seen on the Nikon website.
Sources: AAAS/Eurekalert! via Marine Biological Laboratory