1、success and failure in adaptationdr anne-marie grisogonoresearch leader land systemsland operations division, dstoscope and objectives interested in systems that adapt including natural (living) and engineered systems and also hybrid sociotechnical systems both individual systems and populations of

2、systems open systems that exist in and interact with a context (physical environment + other systems) through porous boundaries understand and exploit the power of adaptation to generate useful new characteristics (design), to solve complex problems, to develop comparative advantage over competing s

3、ystems to develop effective cooperative strategies between systems to do this - need to understand how adaptation works, and how and why it succeeds or fails.distinguish success/failure of mechanism of adaptation from needed successes and failures within adaptationhow does a living system make a liv

4、ing? import resources to function and reproduce, and fight decay through homeostasis, self- repair and exporting wastesystems ability to sense, process & act on its own behalf depends on what problems system has to solve to find resources and protect itself from danger i.e. on system and context

5、how hard is this?systems ability to adaptcomplexity of contextcomplexity of context(from the systems pov)some observations on fitness fitness depends on both system and its context. doesnt make sense to talk about system fitness independently of its contextideal fitness for natural systems: intrinsi

6、c and objective; or externally observed, but subjective for engineered or hybrid systems: externally defined by designer versusinternalised fitness as deducible from the way selection actually operates objective measure.variation-evaluation process needs to produce fitness (or proxy) -relevant feedb

7、ackadaptation needs to employ proxies for intrinsic fitness if timescale over which it needs to operate is faster than timescale over which observable measures of fitness materialise for feedback to selection process (holds for some learning adaptations)natural proxies are themselves the product of

8、evolution (i.e. adaptation) so degree of correlation with ideal fitness should be high when selection pressure is strong but if environment changes faster than evolution can adapt the proxies, then significant misalignment can develop.for engineered or hybrid systems, look at correlation of proxies

9、with ideal fitness! choosing proxies is a critical issue for engineered or hybrid systemswhy do systems fail?some examplesfailure of adaptationany other causes?systems thrive or fail in their context when context changes they need to adapt failure to adapt system failureinaccurate selection eg super

10、stitions, phobias= trapped in pseudo-attractor in fitness spacepremature convergence i.e. overadapted to highly specialised role with concomitant loss of adaptivity eg retrenched professional; sunk cost = loss of ability to move in fitness spacerapid environmental change eg species extinction result

11、ing from end of ice age= failure to adapt quickly enough to changecorrelation of internalised fitness proxy with actual fitness declines eg our penchant for foods rich in fats and sugars = failure to fitness-linkage in selectionoverexploitation of resources eg easter island = failure to detect impen

12、ding decline and /or failure to produce effective responsewhat is success or failure of a system? absolute measure? sort of but not very satisfactory: only of failure system dies or ceases to exist duration of system life could then be one success measure but what about quality of life? can only mea

13、sure it when it dies, if system changes significantly is it still the same system? and a successful system then is one that simply hasnt yet failed so what is success or failure of a system?but since success is transient at best in changing context - also need a relative success at a point in time:

14、for an individual system, relative to other systems: health integrity, level of functioning, how much above the line is it? free resources to shape its environment cumulative products offspring, useful output, available option space trust and respect accorded, resources controlled, acquired capabili

15、ties and strategieswhat is success or failure of a population of systems?relative success at point in time for a population of systems: size of population growth rate, or stability of population fraction of environmental resources utilised or fraction of suitable fitness surface that is found and po

16、pulated but as population moves, the landscape doesnt stand still so speed with which population can move in the fitness landscape and get off regions of declining value and find new suitable regions as they emergewarningwarning: this diagram is a : this diagram is a gross oversimplificationgross ov

17、ersimplification but usefully suggestive. but usefully suggestive.a fitness landscape with 2 degrees of freedompopulatedhabitable thresholdpotential niche what is important for the success or failure of a population of systems?through evolution, populations migrate towards regions of higher fitness

18、and carve out viable trajectories in design space.dimensions of occupied region diversity of characteristics in populationover time branchings, speciations, extinctions topology of fitness surface accessibility of unpopulated nicheshow can we quantify a populations agility in design space?what imped

19、es or facilitates it?ability of a population to:1. protect and expand regions of design space already populated, throughstabilisation of useful properties against harmful variation, being tolerant to external changes, and acting on the environment in a way that increases its habitability, and 2. mov

20、e in design space, away from areas of reduced or reducing fitness and towards areas of greater or growing fitnessfactors for success or failure of adaptationfor populations of systems:factors of successspeed of moving in fitness landscape to get off regions of declining fitness and find new suitable

21、 regions as they emerge ability to stabilise, protect useful propertiesability to modify environment to maintain or increase habitability locally to current population, and foster emergence of habitable regions elsewherefactors of failureloss of agility in design space, eg by overspecialisation, red

22、uced diversityloss of useful information leading to mutational meltdownpropensity to act on the environment in such a way as to decrease habitability either locally, or elsewherefor individual systems:factors of successspeed of moving in own fitness landscape, replacing capabilities of lower or decl

23、ining fitness with new ones better suited to creating success in context, ability to stabilise, protect useful propertiesability to modify environment to maintain or increase habitability locally, or foster emergence of habitable regions elsewherefactors of failureloss of agility eg by overspecialis

24、ation, getting set in its waysloss of useful information forgetting what it has learntacting in ways that decrease habitability locally, or elsewhere, eg by prioritising short-term gains over longer-term consequenceshow to study and quantify these factors and what influences them?what adaptation isw

25、hat steers it implementation strategieswhat it deals withwhat aspect of the system is adaptingwhere it is applied what it takes to make them work what it takes to improve themconceptual framework for adaptationgeneric model of adaptation measures of success and failure types of adaptive mechanismsfo

26、ur classes of adaptationfive levels of adaptationscale of adaptive mechanismshealth of adaptive mechanisms factors that influence effectivenessvariation, interaction, feedback, selectionmos, mof, proxies, indicators, correlationspopulation size, cycle time, randomness, parallelismstressor parameters

27、, effects and time scalesadaptability of system and adaptation parameterssystem parameters, sense, process and act scalescontinuity, throughput, alignment, driveother parameters that characterise adaptation mechanismsee references in textwhat gets triedhow its evaluatedhow its retained or discardedt

28、ime constant of context(some of) what influences success or failure of adaptationability to move in fitness spaceability to find and exploit opportunitiesand recognise & deal with threatsability to protect the good regions of design space already populatedability to specialise but retain agility

29、 how well system produces new optionshow well system evaluates new optionssize of population depth, scope, concurrency of variations increases space enormously but access higher order effectsrate of variation what aspects are variableto produce higher order structure, existence of variable system parameters that create the possibility for enduring relationships between sy