Watch zebrafish cells chase each other into patterns!

An amazing article from Ed Yong describes a new mechanism for pattern formation:

Coloured Cells Chase Each Other To Make A Fish’s Stripes

Zebrafish patterns aren’t just controlled by a chemical reaction-diffusion mechanism — the pigment cells actually chase each other! The different color cells sort themselves into stripes, spots, or other patterns depending on their relative speeds.

dvdp:

Today’s Smile by qubibi

<meta property=“og:description” content=
This is a website I created after being affected by the 3.11 Earthquake in Japan,
and the nuclear power plant incidents that followed.”

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UPDATE 2012-02-05
Shortly after I’ve posted this The Daily Dot wrote more about
qubibi (Kazumasa Teshigawara), the process and emotions behind this work.

fuckyeahfluiddynamics:

In the ocean, many forces compete in driving convection, including the temperature and salinity of the water. In the laboratory, it’s possible to mimic these characteristics of oceanic circulation using two different fluids driven by temperature and concentration differences. Recently, researchers were exploring this problem—with the added twist of tilting the fluids ~1 degree—when they discovered a surprising result. After an extended time, the convection self-organized into alternating parallel columns of ascending (dark) and descending (light) fluid. The researchers nicknamed this behavior super-highway convection. Read more about it here or in their paper. (Video credit: F. Croccolo et al; submitted by A. Vailati)

Image 1: “Scanning electron microscope image of a bryozoan colony” (Source)

Image 2: “This skeleton of a living bryozoan, collected at Bahia de los Angeles, Baja California, clearly shows this typical colonial organiation.

Each individual, or zooid, is enclosed in a sheath of tissue, the zooecium, that in many species secretes a rigid skeleton of calcium carbonate. Each zooid in this electron micrograph is less than a millimeter long and has a single opening, the orifice. Through this opening, the lophophore, a ring of ciliated tentacles centered on the mouth, protrudes to capture small food particles. The lophophore can be retracted very rapidly by specialized retractor muscles, and the opening closed by a doorlike operculum, visible on some of the zooids in the picture at the left.”

Source

Image 3: Membraniporella nitida (source) cc-by-nc-sa

More info: http://en.wikipedia.org/wiki/Bryozoa

Gonodactylus platysoma, UV-excited fluorescence

From http://arthropoda.southernfriedscience.com/?p=2592 : 
I talked previously about fluorescence in stomatopods here. However, I don’t know if the patterns on G. platysoma are used to amplify any particular signals. These animals live in shallow water and would have less use for fluorescent signal amplification.”

Madreporites on sea stars

The madreporite is a lightcolored calcerous opening used to filter water into the water vascular system of echinoderms. It acts like a pressure-equalizing valve. […] Close up, it is visibly structured, resembling a “madrepore” (stone coral, Scleractinia) colony.” — Wikipedia

Image 1: Madreporites, from Pierce and Maugel’s 1987 Illustrated Invertebrate Anatomy (via “How Starfish Move”)

Image 2: Madreporite of Henricia pumila:The madreporite is creamy colored as in the type specimen.  Notice the papulae extended among the pseudopaxillae.” (Source)

I don’t know what to call this pattern, but I like it!

Image 1: “The Maze” by Debralee Wiseberg (link and another gallery)… I think it’s corroded metal?

Image 2: 2,2-(Bipyridine)(Naphthalene)-fusion melt (25x)

Herb Comess. Honorable Mention, 1994 Nikon Small World Photomicrography Competition (link)

XXLux 

by Barbara Doser and Hofstetter Kurt, 2006

medien.KUNSTLABORKunsthaus Graz

Caption:

A screening of ecstatic moments created with the Video Feedback technique at the event horizon of perceptible worlds of image and sound while generating a moving picture. Moments distilled from experimental videos and compiled into a new unit.

Video Feedback is mapping (imaging) any visual event (image) to itself through parallelism and circulation. A minimum change of its instrument positions (video camera | screen) generate a maximum of stimuli at the time-based event horizon of perception. A flood of rapidly changing abstract images on the move will be experienced as a world of spatial complexity and of dynamic states.”

Source: http://www.sunpendulum.at/parallelmedia/time-no-time-01/xxlux.html

Background info on optical feedback

An example of Optical feedback

Image source: http://en.wikipedia.org/wiki/File:Optical-feedback-2-short.gif

Examples of dynamic optical feedback image on television monitor

Image source: http://en.wikipedia.org/wiki/File:Optical_feedback-2ex-vsm.jpg

More information: http://en.wikipedia.org/wiki/Optical_feedback

More animations from this Wikimedia gallery of animations from Conway’s Game of Life!

Pulsar (period 3)

Another 3-period oscillator

8-period oscillator

This one’s also really cool, but it’s not uploading for some reason