The rainbow creatures shown here are a species called calcareous nannoplankton.
In the past as ocean acidity increased, the skeletons of some species became malformed, other species shrank in size, and others died out altogether. The intelligent design behind the species portrayed here is that it modifies and protects itself with a calcium shell during periods of high CO2 atmospheric content that lead to ocean acidification. Each creature is approximately 2 microns.
This image was taken with an Environmental Scanning Electron Microscope, which allows us to see nanostructures in their native state with extraordinary three-dimensional clarity. ESEM images are originally black and white. But colors can be added subsequently (in order to give better clarity to the image) by assigning a given color to a specific gray scale.