James P. Crutchfield - Is Anything Ever New? Considering Emergence (1999)

James Crutchfield is a veteran of the Santa Fe institute and director of UC's Complexity Sciences Center. From an information-theoretic standpoint, he here considers the optimal approach for an observer to explain the behaviours emerging from a black-box natural system. The solution put forward here is to attempt to built a machine which generates a corresponding output, minimising:

• the model size, and
• the error margin between our model and the observed data

From the complexity of this model (which here takes the form of an FSA-like ε-machine), we can deduce the structural complexity of the underlying natural system. These ideas form the core of the computational mechanics field, behind which lie Crutchfield, Shalizi and others.

It's an incredibly dense yet engaging paper, itself a reduction of The Calculi of Emergence (pdf), probably the most essential piece of work on quantifying emergence and effective complexity.

Fortify your gardens: BBC News reports (based upon this paper) that a novel ultra-invasive ant species, Lasius neglectus, is soon to strike the cold temperate climes of Northern Europe. This new strain is creating supercolonies that are orders of magnitude greater than existing colonies, based on the seemingly counter-evolutionary development of a flightless queen, alongside workers that are willing to mate within their colony rather than first taking flight to pastures new. Moreover, it's a relatively unaggressive form, constituted by "a social system that is characterized by mating without dispersal and large networks of cooperating nests rather than smaller mutually hostile colonies".

As a consequence, it's exhibiting self-organization on a staggering (and somewhat frightening) scale, resulting in single vast populations that inexorably expand outwards. Courtesy of human transport to locations that lack natural parasites (cite, PDF), Lasius neglectus has begun to blanket central Europe over the course of just 25 years.

The authors conclude that:

"Our results show that invasive L. neglectus populations are a potential problem of global dimensions, and a particular threat for man-made ecosystems in the cold-temperate climate zones that have so far suffered very little from invasive ants."

I, for one, welcome our new insect overlords.