Incredibly Small: Best Microscope Photos of the Year.

Every year for nearly four decades, Nikon has received hundreds of entries in its Small World microscope photography contest. Every year, the images are more amazing, and this year’s winners — selected from nearly 2,000 submissions — are undoubtedly the best yet.

Super-close-ups of garlic, snail fossils, stinging nettle, bat embryos, bone cancer and a ladybug are among the top images this year. The first place winner (above) shows the blood-brain barrier in a living zebrafish embryo, which Nikon believes is the first image ever to show the formation of this barrier in a live animal.

“We used fluorescent proteins to look at brain endothelial cells and watched the blood-brain barrier develop in real-time,” the winners, Jennifer Peters and Michael Taylor of St. Jude Children’s Research Hospital, in Memphis, said in a press release. “We took a 3-dimensional snapshot under a confocal microscope. Then, we stacked the images and compressed them into one – pseudo coloring them in rainbow to illustrate depth.”

Here are the top 20 photomicrographs from the 38th Nikon Small World competition, selected for their originality, informational content, and visual impact by a panel of scientists, journalists and optical imaging experts.

Above, the blood-brain barrier in a live zebrafish embryo by Jennifer Peters and Michael Taylor, St. Jude Children’s Research Hospital, Memphis, Tennessee.

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