Real, unreal, surreal

“I don’t do drugs. I am drugs” ~ Salvador Dalí.

The photo, which dates from 1969, depicts the 65-year-old Catalan surrealist Salvador Dalí emerging from a Paris subway station led by his trusty giant anteater. Surrealism‘s aim was to “resolve the previously contradictory conditions of dream and reality.” Artists painted unnerving, illogical scenes with photographic precision, created strange creatures from everyday objects and developed painting techniques that allowed the unconscious to express itself. [from Wikipedia, link above].

The Hacker and the Ants

The Hacker and the Ants is a work of science fiction by Rudy Rucker published in 1994 by Avon Books. It was written while Rucker was working as a programmer at Autodesk, Inc., of Sausalito, California from 1988 to 1992. The main character is a transrealist interpretation of Rucker’s life in the 1970s (Rucker taught mathematics at the State University College at Geneseo, New York from 1972 to 1978. from Wikipedia). The plot follows:

(…) Jerzy Rugby is trying to create truly intelligent robots. While his actual life crumbles, Rugby toils in his virtual office, testing the robots online. Then, something goes wrong and zillions of computer virus ants invade the net. Rugby is the man wanted for the crime. He’s been set up to take a fall for a giant cyberconspiracy and he needs to figure out who — or what — is sabotaging the system in order to clear his name. Plunging deep into the virtual worlds of Antland of Fnoor to find some answers, Rugby confronts both electronic and all-too-real perils, facing death itself in a battle for his freedom. (…)

On Zeus, ants and Men

Fig. – Zeus turns ants into Men thus populating the Island of Aegina, his nymph above right next to the eagle (this lovely 17th century drawing was sent by a friend, Isabel Figueiredo). Some sources also say Zeus turned himself into an eagle before doing this.

According to the Greek mythology the island was inhabited when Zeus had a romantic interlude with the nymph Aegina there and had a son, Aecaus (later, grandfather of Achilles). Zeus, at the request of Aecaus populated the island so Aecaus would have subjects in his kingdom (source). Those inhabitants were entitled Myrmidons:

“These were men created from ants on the island of Aegina, in the reign of Aeacus, Achille’s grandfather, and they were Achilles’ followers in the Trojan War. Not only were they thrifty and industrious, as one would suppose from their origin, but they were also brave. They were changed into men from ants because of one of Hera’s attacks of jealousy. She was angry because Zeus loved Aegina, the maiden for whom the island was named, and whose son, Aeacus, became its king. Hera sent a fearful pertinence which destroyed the people by thousands. It seemed that no one would be left alive. Aeacus climbed to the lofty temple of Zeus and prayed to him, reminding him that he was his son and the son of a woman the god had loved. As he spoke he saw a troop of busy ants. “Oh Father,” he cried, “make these creatures a people for me, as numerous as they, and fill my empty city.” A peal of thunder seemed to answer him and that night he dreamed that he saw the ants being transformed into human shape. […] So Aegina was repopulated from an ant hill and its people were called Myrmidons after the ant (myrmex) from which they had sprang.” (Hamilton, Edith, Mythology, Warner Books, New York, 1969)

Aegina is the 2nd closest island to Athens after Salamina at the Saronic Gulf, with 86 square Kms and a current population of 12000 people. The island is home to one of the most beautiful temples of late Archaic Greece, the temple of Aphaia. A volcanic island with plains of respectable fertility to the northern and southern parts. Aegina is also where the famous pistachio nuts can be  found alongside the other main produce of the island, grain, vines, almonds and olives. The southern end of the island is rocky and barren. The highest peak of the island is Mt. Oros.

Sticky neurons

Time-lapse imaging in live zebrafish embryos reveals that cerebellar granule cells migrate in chain-like structures as discovered by a recent article [1] [Köster et al., PLoS, Nov. 2009]. Figure above – Granule cells taken from the cerebellum of a pigeon (above, B) are shown in this 1899 drawing by legendary neuroscientist Santiago Ramón y Cajal.

Did talk about sticky objects and self-organization in the past,  how positive and negative feedback’s  stigmergic-like agents integrated could promote changes and learning over a complex system.  Same happens to bacteria as also ants. On the other hand, we do know memes are also sticky (e.g. Chip Heath, Dan Heath, “Made to Stick: Why Some Ideas Survive and Others Die“, Random House, ISBN 978-1-4000-6428-1, January 2007). What’s new however, is that there are increasing proofs that our own brains my follow similar mechanisms (as Douglas Hofstadter in the past did made some analogies with how brains could work and how ant colonies raid different environments). In this recent new study, Köster and colleagues [1] [PLoS, Nov. 2009] reveal crucial pieces of this puzzle, showing how (neuronal) cells orient themselves to migrate together (like bacteria, above). The team studied zebrafish, one of the workhorses of developmental neurobiology, because its transparent body allows researchers to track movements of cells inside of it. As explained by Mason Inman [2]:

[…] Neurons in the developing brain complete their own self-organized waltz, coordinating with their neighbors to migrate to the right spots to form the cerebellum, visual cortex, or other parts of the brain. In this issue of PLoS Biology, Reinhard Köster and colleagues show that some of these brain cells behave much like slime molds, coordinating with other cells of the same type to migrate in a herd. They found that one particular protein called Cadherin-2 is crucial in allowing the cells to adhere to their neighbors so they can coordinate their movements and all wind up in the right spot. […] Slime molds provide a textbook example of self-organization. They live as single cells until food becomes scarce. Then, they broadcast chemical signals that trigger their mass assembly into a fruiting body, with some cells forming a stalk and others turning into spores that cast about in the winds to spread far and wide. […] Neurons in the developing brain complete their own self-organized waltz, coordinating with their neighbors to migrate to the right spots to form the cerebellum, visual cortex, or other parts of the brain. In this issue of PLoS Biology, Reinhard Köster and colleagues show that some of these brain cells behave much like slime molds, coordinating with other cells of the same type to migrate in a herd. They found that one particular protein called Cadherin-2 is crucial in allowing the cells to adhere to their neighbors so they can coordinate their movements and all wind up in the right spot.[…]

[…] But the mechanisms behind this coordinated movement – in particular, how each cell adjusts its inner workings to move to the right place at the right time – are only now starting to be revealed, using imaging that tracks these cells in live animals as they develop. […] To figure out what triggers the cells to line up and move together, the authors looked at what other kinds of cells were in the neighborhood. Many studies have shown that support cells, known as glial cells, often help guide neurons during these kinds of migrations. But during the first few days of the zebrafish embryo’s development, Köster and colleagues found, there were no glial cells along the granular cells’ migration route. That means these cells must go it alone, the team reasoned, with their own mechanism for signaling between each other to line up into chains and make their move. […] Although the study focused on just one type of brain cell, the findings could explain how many types of neurons find their way to their proper spots as the brain develops. There are still some pieces of the puzzle missing, however. While the findings explain how the granule cells are able to coordinate and follow their neighbors, it’s still not clear how the first few cells to head out on the journey – those at the front of the “conga line” – get oriented in the right direction. This suggests there must be some kind of signal from surrounding cells to get them headed in the right direction, the authors argue – yet another level of organization. […] , in Mason Inman (Nov., 2009) Migrating Brain Cells Stick Together, PloS. [2]

[1] Rieger S, Senghaas N, Walch A, Köster RW (Nov., 2009) Cadherin-2 Controls Directional Chain Migration of Cerebellar Granule Neurons. PLoS Biology.
[2] Mason Inman (Nov., 2009) Migrating Brain Cells Stick Together, PloS Biology.