Before the memristor, it would have been impossible to create something with the form factor of a brain, the low power requirements, and the instantaneous internal communications. Turns out that those three things are key to making anything that resembles the brain and thus can be trained and coaxed to behave like a brain. In this case, form is function, or more accurately, function is hopeless without form. [...]

A memristor is a two-terminal device whose resistance changes depending on the amount, direction, and duration of voltage that’s applied to it. But here’s the really interesting thing about a memristor: Whatever its past state, or resistance, it freezes that state until another voltage is applied to change it. Maintaining that state requires no power. That’s different from a dynamic RAM cell, which requires regular charge to maintain its state. The upshot is that thousands of memristors could substitute for massive banks of power-hogging memory. Just to be clear, the memristor is not magic—its memristive state does decay over time. That decay can take hours or centuries depending on the material, and stability must often be traded for energy requirements—which is one of the major research reasons memristors aren’t flooding the market yet. [...]

A biological brain is able to quickly execute this massive simultaneous information orgy—and do it in a small package—because it has evolved a number of stupendous shortcuts. Here’s what happens in a brain: Neuron 1 spits out an impulse, and the resultant information is sent down the axon to the synapse of its target, Neuron 2. The synapse of Neuron 2, having stored its own state locally, evaluates the importance of the information coming from Neuron 1 by integrating it with its own previous state and the strength of its connection to Neuron 1. Then, these two pieces of information—the information from Neuron 1 and the state of Neuron 2′s synapse—flow toward the body of Neuron 2 over the dendrites. And here is the important part: By the time that information reaches the body of Neuron 2, there is only a single value—all processing has already taken place during the information transfer. There is never any need for the brain to take information out of one neuron, spend time processing it, and then return it to a different set of neurons. Instead, in the mammalian brain, storage and processing happen at the same time and in the same place.

That difference is the main reason the human brain can run on the same power budget as a 20-watt lightbulb. [...]

To build a brain, you need to throw away the conceit of separate hardware and software because the brain doesn’t work that way. In the brain it’s all just wetware. If you really wanted to replicate a mammalian brain, software and hardware would need to be inextricable. We have no idea how to build such a system at the moment, but the memristor has allowed us to take a big step closer by approximating the biological form factor: hardware that can be both small and ultralow power. [...]

http://spectrum.ieee.org/robotics/artificial-intelligence/moneta-a-mind-made-from-memristors/0

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Self-replication of information-bearing nanoscale patterns:”DNA molecules provide what is probably the most iconic example of self-replication—the ability of a system to replicate, or make copies of, itself. In living cells the process is mediated by enzymes and occurs autonomously, with the number of replicas increasing exponentially over time without the need for external manipulation. Self-replication has also been implemented with synthetic systems, including RNA enzymes designed to undergo self-sustained exponential amplification. An exciting next step would be to use self-replication in materials fabrication, which requires robust and general systems capable of copying and amplifying functional materials or structures. Here we report a first development in this direction, using DNA tile motifs that can recognize and bind complementary tiles in a pre-programmed fashion. We first design tile motifs so they form a seven-tile seed sequence; then use the seeds to instruct the formation of a first generation of complementary seven-tile daughter sequences; and finally use the daughters to instruct the formation of seven-tile granddaughter sequences that are identical to the initial seed sequences. Considering that DNA is a functional material that can organize itself and other molecules into useful structures, our findings raise the tantalizing prospect that we may one day be able to realize self-replicating materials with various patterns or useful functions.” http://www.nature.com/nature/journal/v478/n7368/full/nature10500.html

Cf.: http://www.sciencedaily.com/releases/2011/10/111012132651.htm

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Planets with Stabilizing Moons May Be Common: “The Earth’s comparatively massive moon, formed via a giant impact on the proto-Earth, has played an important role in the development of life on our planet, both in the history and strength of the ocean tides and in stabilizing the chaotic spin of our planet. Here we show that massive moons orbiting terrestrial planets are not rare. A large set of simulations by Morishima et al. (Morishima, R., Stadel, J., Moore, B. [2010]. Icarus. 207, 517–535 [cf. http://arxiv.org/pdf/1007.0579 ]), where Earth-like planets in the habitable zone form, provides the raw simulation data for our study. We use limits on the collision parameters that may guarantee the formation of a circumplanetary disk after a protoplanet collision that could form a satellite and study the collision history and the long term evolution of the satellites qualitatively. In addition, we estimate and quantify the uncertainties in each step of our study. We find that giant impacts with the required energy and orbital parameters for producing a binary planetary system do occur with more than 1 in 12 terrestrial planets hosting a massive moon, with a low-end estimate of 1 in 45 and a high-end estimate of 1 in 4.” http://arxiv.org/pdf/1105.4616

Cf. http://theunitedpersons.org/blog/planetary-anthropic-selection

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Beyond Darwin: Ways to Evolve New Functions – At a recent Kavli Futures Symposium, nineteen experts from a diverse range of fields discussed the promise of using the lab to understand and exploit the evolution of organisms — an advance that may one day be used to develop new vaccines or other biotechnology products. https://www.kavlifoundation.org/kavli-futures-symposium-evolution-new-functions-main

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All complex systems contain parasites. In any system of cooperative behavior, an uncooperative strategy will be effective — and the system will tolerate the uncooperatives — as long as they’re not too numerous or too effective. Thus, as a species evolves cooperative behavior, it also evolves a dishonest minority that takes advantage of the honest majority. If individuals within a species have the ability to switch strategies, the dishonest minority will never be reduced to zero. As a result, the species simultaneously evolves two things: 1) security systems to protect itself from this dishonest minority, and 2) deception systems to successfully be parasitic.

Humans evolved along this path. The basic mechanism can be modeled simply. It is in our collective group interest for everyone to cooperate. It is in any given individual’s short-term self interest not to cooperate: to defect, in game theory terms. But if everyone defects, society falls apart. To ensure widespread cooperation and minimal defection, we collectively implement a variety of societal security systems.

Two of these systems evolved in prehistory: morals and reputation. Two others evolved as our social groups became larger and more formal: laws and technical security systems. What these security systems do, effectively, is give individuals incentives to act in the group interest. But none of these systems, with the possible exception of some fanciful science-fiction technologies, can ever bring that dishonest minority down to zero.

In complex modern societies, many complications intrude on this simple model of societal security. Decisions to cooperate or defect are often made by groups of people — governments, corporations, and so on — and there are important differences because of dynamics inside and outside the groups. Much of our societal security is delegated — to the police, for example — and becomes institutionalized; the dynamics of this are also important. Power struggles over who controls the mechanisms of societal security are inherent: “group interest” rapidly devolves to “the king’s interest.” Societal security can become a tool for those in power to remain in power, with the definition of “honest majority” being simply the people who follows the rules.

The term “dishonest minority” is not a moral judgment; it simply describes the minority who does not follow societal norm. Since many societal norms are in fact immoral, sometimes the dishonest minority serves as a catalyst for social change. Societies without a reservoir of people who don’t follow the rules lack an important mechanism for societal evolution. Vibrant societies need a dishonest minority; if society makes its dishonest minority too small, it stifles dissent as well as common crime. https://www.schneier.com/blog/archives/2011/05/status_report_t.html

Cf. https://www.schneier.com/blog/archives/2011/02/societal_securi.html

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(coenzyme Q10 http://en.wikipedia.org/wiki/Coenzyme_Q10 , phosphatidylcholine http://en.wikipedia.org/wiki/Phosphatidylcholine , and vitamin D http://en.wikipedia.org/wiki/Vitamin_D )

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Breakthrough to bridge the gap between man and machine: a research team has developed a technique for mapping both the connections and functions of nerve cells in the brain https://www.ucl.ac.uk/news/news-articles/1104/11041102

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Genetic explanation for eusociality

“Are there genes that are unique to the primitively eusocial bees that aren’t found in the highly eusocial bees?” Cameron said. “Or if you lump all the eusocial bees together, are there unique genes that unite those groups compared to the solitaries?”

The analysis did find significant differences in gene sequence between the eusocial and solitary bees. The researchers also saw patterns of genetic change unique to either the highly eusocial or primitively eusocial bees. The frequency and pattern of these changes in gene sequence suggest “signatures of accelerated evolution” specific to each type of eusociality, and to eusociality in general, the researchers reported.

“What we find is that there are some genes that show signatures of selection across the different independent evolutions (of eusocial bees),” Robinson said. “They might be representatives of the ‘gotta have it’ genes if you’re going to evolve eusociality. But others are more lineage-specific.”

http://www.eurekalert.org/pub_releases/2011-04/uoia-gso040811.php

Cf. http://www.zotero.org/mazsa/items/collection/HNS2HG7F

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It is widely recognized that regions of Earth that have stable temperatures (e.g., tropical rainforests) have high levels of biodiversity (see review by Wilson, 2001). The hypothesis that this link is direct and causal is reinforced by the observation that the deep ocean seafloor also has high biodiversity (Sanders, 1968), even though the conditions are, stability excepted, poor and biological productivity therefore low. Further evidence of a link between rapid climate change and loss of species richness has been gleaned from studies of Earth’s glacial-interglacial cycles. The most recent ice ages have resulted in reduced biodiversity within the temperate zones where the greatest changes in climate occurred (see review by Hewitt, 2004). There are, therefore, two independent lines of evidence that support the proposition that biodiversity is, in general, lower when climate change is significant. [...]” http://www.liebertonline.com/doi/pdf/10.1089/ast.2010.0475

Cf. http://theunitedpersons.org/blog/the-great-filter-are-we-almost-past-it

Update: http://theunitedpersons.org/blog/planets-with-stabilizing-moons-may-be-common

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OS sw designed to minimize synthetic biology risks http://www.eurekalert.org/pub_releases/2011-03/vt-osd032111.php

http://genothreat.sourceforge.net/

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