Fluorescent colors of the reef - why corals need colors

   Corals, like many representatives of marine life, are known to be strikingly colourful creatures. However, understanding the nature of those colours can be tricky. The most problematic part: there's no such thing as colour outside your head. Light differs in wavelength and those differences can be picked up by various receptors in the eye. Colours, in contrast, are born in the secondary visual cortex in the brain after a lot of information is processed. The brain decides how to render the information from the retina based on the context of the whole image. In other words, there's no easy correspondence between wavelength and colour. Every photographer is familiar with this concept as part of white balance correction.

Viable Ancient Choanoflagellates from Siberian Permafrost

  Choanoflagellates are the closest unicellular relatives of the animals (Metazoa).

  They seem like very simple organisms. They have a flagellum and a collar, similarly to sponge choanocytes. They use these structures to capture bacteria. Some species have other external structures, such as basket-looking loricas and thecas.
 
Read more about choanoflagellates here and here.

  Choanoflagellates are very common in freshwater and marine environments and they look very gentle and fragile. Yet they managed to survive for around 28-50 thousand years in one of the most extreme environments on Earth. Part of my research was about studying these amazing protists that we found in the Siberian permafrost.