Noble Ape Blog

Here’s a plot depicting the average percentage of first person episodic memories over a period of a couple of months of simulation time. The vertical axis is multiplied by a factor of ten. A first person memory is one acquired from direct personal experience, whereas second hand memories are acquired from other apes via the telling and re-telling of anecdotes.

Over time the percentage of first person memories is slowly decreasing as anecdotes (scurrilous or otherwise) spread throughout the population and displace them in a competition for mindshare. This is the beginnings of a sort of persistent culture based upon accumulated shared experience.

For anyone who is a newcomer to Noble Ape here is a high level overview of the genetics and how it operates.  This system is loosely, although not literally, based upon biological genetics. Currently there are no epigenetic switches, but that also might be added in later versions.

Chromosomes

Each individual has four diploid chromosomes, each consisting of 32bits with 2 bits per base. An example genome looks like the following:

This may not look like much, but the genome could better be thought of as a program or a combinatorial system which can generate a larger set of information from a relatively small genetic origin.

Recombination

At conception we have the familiar crossover and mutation operators, along with the possibility for deletions or insertions. The crossover point for each chromosome is randomly selected.

In many genetic algorithms only point mutations provide a source of novelty, but here in addition a few types of transcription can also occur. With some probability, sections of the genome may be copied from one location in a chromosome to another, or between chromosomes. During transcription a chunk of genetic code may sometimes become inverted whilst in transit. This is a major source of genetic change and differences between siblings.

Genes

Gene values corresponding to, or influencing, phenotypic traits are extracted from the genome by taking pairs of bases from different locations and joining them together to make a single 4 bit value. The locations for the two bases are not necessarily sequential and are specified by regulator genes in separate areas of the genome. This means that phenotypes are a product of a web of inter-connected genes, and that an alteration in one gene might also have cascading effects upon others, resulting in non-trivial dynamics over successive generations. Changes in regulator genes may also have multiple effects on other genes, in line with the idea of punctuated equilibrium in evolution.

Some genes are sex linked. The first chromosome is inherited exclusively down the male or female line, such that a daughter inherits chromosome 1 from her mother and a son inherits chromosome 1 from his father. The outcome is that there can be sexual dimorphism in various characteristics, such as appearance and mating preferences.

Genes influencing physical appearance

These genes are sex linked, so that males and females may have different versions of the gene.

Genes influencing psychology

Genes influencing behavior

Genes influencing mating preferences

These genes are sex linked, such that males and females may have different versions of the gene.

Genes related to production of digestive enzymes

The efficiency of nutrient absorption for any food type is based upon a normalized weighted sum of these values. This helps to prevent an uninteresting scenario where all these values are driven to maximum, and creates trade-offs and the possibility for specialist grazers.

Inheritance

The double chromosomes also facilitates Mendelian inheritance, such that genes may be inherited but remain latent, with the possibility of them being expressed only in some later generation. This increases the informational carrying capacity of the genome, facilitating biodiversity. It also means that mutations or changes due to transcription may not necessarily be expressed in the current generation, but may turn up later.

Not by genes alone

There’s a fair amount of genetic determinism within Noble Ape, but genes don’t completely determine behavior or survival value.  Largely in parallel to the genetics there is a system of cultural transmission, supported by the cognitive system, which can evolve independently.

Here’s a TED video about the curious nature of the self.

Anyone who is interested in AI or intelligent machines will inevitably eventually have to confront the nature of the self and its curious malleability.  As Ben Goertzel mentioned in “The Hidden Pattern” intelligence is really something which exists between minds as much as it does within them, and it’s in multi-mind simulators such as Noble Ape that these ideas can be explored.

The above video I think has some relevant points: the idea of the self as a constellation of elements which are not necessarily localized, and the idea of consciousness as an “illusion” or “trick”.  However I don’t think this goes quite far enough.  IMHO the “trick” is really a virtual machine, and the trans-personal nature of intelligence are mobile programs, or “programs in the wild”.  When the elements of the brain are arranged in some way and there is a means of communication with just enough bandwidth and generativity then it becomes a suitable initiator and host of virtual machines which can move around, combine, compete and so on.

As people such as Stephen Wolfram have found, it doesn’t take much to make a Turing machine.  My guess is that that computation is ubiquitous in all human cultures which contain a generative language, but largely unrecognized and unquantified.  Here I’m not referring to digital computers or modern infomatics – which are one example of computation – nor the genome which can be thought of as a Turing machine operating with 3D molecules rather than transistors or tape.  So I think that the self is a kind of virtual machine which may be highly localized (as in a hermit living in a cave) or more typically as a distributed entity across multiple minds, including those minds which have become fossilized within cultural artifacts.

The self also seems to have a scale free nature, such that the identity of a group can be similar to the identity of an individual, or vice versa.