What is the 'end point' for evolution?

Please excuse an extensive preamble, setting forward the various cases for this involved metaphysical question: Intrinsic to any 'process' is a tendency towards a certain state. I would suggest this is by definition, because if there was no such driven direction then it would be difficult to classify them as a 'process' if they have no definite outcome you can observe. (Otherwise you wouldn't know if anything particular has happened!) This may be as simple as the process of a falling ball to ground or, as is well-known now, dynamical systems that pass through, but remain on, a possibly highly complex set of states such as described by 'Lorentz' butterfly'.

So if we now consider evolution (by which I mean, and accept as, the process which has lead to fundamental genetically derived traits being carried into more complex successor organisms), then what do the definitions of those processes within evolution tell us about the 'ultimate' future of life?

A) If we work on the basis that evolution is about improvement of individual species, then is it saying that we would see an irresistible improvement to 'an ultimate organism' through the processes of reproduction and variation to organisms that can accommodate all environmental conditions? Otherwise, presumably there would be no end to evolutionary improvements if it is suggested that there is never an 'end point'. This would demand that "the process of evolution" has some intrinsic idea of what 'a perfect organism' is, else it cannot tend the organism towards that. This means that embedded within evolution is 'the (or at least 'a') meaning of life' itself because if we understand where the fundamental processes of nature are taking life then we would know what the 'end point' and ultimate definition of 'most successful life' would be. We do not need to 'know' what the end point is, that evolution is taking us towards, but it would be a heck of a revelation to simply find out that there was actually some 'ultimate organism' that evolution was tending us towards!

B) If we work on the basis that evolution is about indefinitely continuous changes in the overall genetic composition of an ensemble of different organisms that NEVER leads to the possibility of an 'ultimate organism' or steady-state set of organisms, then this (B) axiom is defined by an inclusion of both 'positive' and 'negative' changes. e.g. the populations may get bigger or smaller, or their size may get bigger or smaller, or brain power, or whatever the trait in question, so long as the organisms remain 'viable' (C, below, covers the 'net-positive' case). The point is that the traits in the organisms will vary in either direction 'indefinitely', because this is the definition of our (B) axiom. (If otherwise, we'd be talking about (C), or (A) again). So this would have to include the possibility that, given an indefinite amount of time, all extant species may find themselves coming simultaneously into evolutionary dead-ends at which point life would die out. (I would suggest that the probability of this happening would likely be the same as life starting in the first place, as this axiom is predicated on a symmetrical process of positive or negative possible changes.) Continuous, unbiased, change demands this ultimate conclusion is possible, at which point life is as unlikely to restart as it was to die out (which would appear to be an infinitesimal probability).

C) We have therefore covered a 'static' super-species conclusion to evolution, a 'continuous change' conclusion and now we can consider 'always positive' evolution. (The 'always negative' evolution is clearly disproved by us discussing this.) For me, this 'always positive' conclusion (by which I am including 'net-positive' which may be "two-steps-forward-one-back", if you like) begins to highlight some of the good scientific points made in answers to my other questions and might help discriminate which is the 'non-science'. It is quite clearly evident that species can die out. This axiom (C) is therefore not applicable to individual species and if this (C) is the answer to the question then it illegitimises evolution in the context of individual creatures. But surely this should be of no surprise because all organisms rely on others, if only to feed off them! (A sub-question could be whether the predator and the predated form a symbiotic relationship!? Yet I presume in a classic notion of evolution, if both are tying to predate each other then they are in competition?) I think this is stretching definitions far too far to make sense. So the only outcome that satisfies me is that continuously positive evolution applies to ensembles of organisms within a collective environment. That is to say, it is our whole biosphere that is evolving. After all, if we take humans then (I am lead to believe) the majority of cells 'within out envelope' (inc. skin and gut) aren't actually human! It makes no sense with this axiom to think of organisms as truly individuals. This axiom, then, also has a conclusion; the whole bio-sphere will evolve into a final (perfect??) state capable of resisting environmental changes (albeit into a complex, but defined, map of states, as per chaos theory). One outcome of this to note, though, is that it means super-successful [over-dominant] species may need to die out to benefit and 'stabilise' the overall bio-sphere's evolution of many, but lesser successful, species.

My question is therefore "what is the end-point to evolution; A) a super-organism, B) continuous change, C) a super-state of biota (that may be generally fixed or periodically pass through a set of chaotic but defined states)?".

(I think I've covered all the 'mathematical' possibilities, are there any others? I am most comfortable with B; that evolution may take us to a point of overall extinction [with the same probability of life starting in the first place] by the undirected variations of species. But I would propose that this changes the definition of evolution from "survival of the fittest" to "collective survival of mutually viable species". This necessarily drops the notion of 'better' or 'worse' and recognises that the evolving traits that are genetically carried through generations, or dropped, are those of ALL the biota, collectively. The notion of "mutually viable species" means that some end-point to life would occur if all extant species spontaneously became "collectively incompatible"! I do not think the inverse process, a requirement for collective compatibility, differs in any significant respect to how life must have had to scratch its way into existence.)

best regards,

Chris MB.

The 'end point' for evolution is extinction.

The laws of thermodynamics impose a temporal limit on the timeframe available for evolutionary processes to continue - eventually they will halt because insurmountable selection pressures (like the sun exploding) will prevent the reproduction required for evolution to continue. Until that time there will be continuous change, if only because mutation is constantly occurring and the world is a dynamic place that will be constantly liable to change, providing variations (however small) in selection pressure. This is effectively your point B.

Every individual organism is a product of the evolutionary process.

The process can be identified by considering the product rather than the 'end point'.

In a nutshell, I agree with Paolo. The endpoint of evolution on Earth will be the extinction of all life (as the economist John Maynard Keynes famously said, "In the long run we are all dead") and continuous change is inevitable in the meantime. These same conclusions apply to any individual species, in that the species will adapt to changing environmental conditions for as long as possible and then ultimately suffer extinction. However, the species may have periods of stasis in its history, interspersed with the periods of evolutionary change, and may also diverge into multiple branches (daughter species of the original mother species, if you like) that may well not go extinct simultaneously. But sooner or later, the entire lineage will die out.

It generally is indeed a good idea to drop notions of 'better' and 'worse' from evolutionary thinking. Evolution is all about adaptation to current local conditions, and the process has no ability to foresee what may happen in the future. The logical of natural selection implies that if a particular trait helps survival in the here and now - regardless of whether it might help, hinder, or be completely neutral in other situations - it will spread through the population and perhaps become universal within the species in question. Humans have found a path to evolutionary success that involves large brains and deft hands, but some taxa do perfectly well by remaining sessile and stupid. There is no evidence for a universal trend towards greater sophistication or complexity: the world was full of prokaryotes (bacteria and simple algae) a couple of billion years ago, and is still full of prokaryotes now, although of course more complex organisms now live alongside them in large numbers.

I would not agree that "the evolving traits that are genetically carried through generations, or dropped, are those of ALL the biota, collectively". It's true that the environment of any given species, to which it must adapt, is partly defined by other species inhabiting the same area. This leads to individual cases of "coevolution", in which two species or groups of species evolve in concert with each other: insects and flowering plants are a classic example. There can also be "arms races" between predator and prey species, or in a sense between ecological competitors. However, there will also be lots of cases in which the species within an ecosystem evolve at different rates, some changing quite rapidly while others (typically the ones doing well under the current conditions) hardly change at all. Individual species will drop out of the ecosystem as a result of extinction, and be replaced by others. "Collective compatibility" is enforced only by the principle that incompatibility between two species in an ecosystem (competition for exactly the same ecological niche, for example) is likely to lead to the extinction of one or the other. This extinction may trigger further ones, but the process should stop well short of the collapse of the whole ecosystem. The idea that Earth's biota is an assemblage of species undergoing some kind of collective evolution strikes me as quite wrong.

As a final philosophical point, I don't think it's true that every process must have a "tendency towards a certain state". Sometimes there can be a range of outcomes, rather than a single one. If you and I sit down to a game of chess, we are engaging in a process that may lead to any of three outcomes from either your perspective or mine: win, lose or draw.