Does Time Equals Complexity?

[Platinum Rhymer]

Do you think that given time, organisms become more and more complex no matter how slow the evolution of complexity is, organisms do get more complex over time?

[A Thousand Pardons]

Do you think that given time, organisms become more and more complex no matter how slow the evolution of complexity is, organisms do get more complex over time?
When did viruses evolve?

[Platinum Rhymer]

I have heard that over time they become more immune to immune systems?

[Cougar]

Do you think that given time, organisms become more and more complex no matter how slow the evolution of complexity is, organisms do get more complex over time?
I used to think so, but I've learned otherwise. There are many examples of evolution toward complexity in the biosphere, but it is not an absolute rule. Evolution has no particular direction, even toward complexity. It's whatever has better reproductive success, for whatever reason. If a creature happens upon a peak in its fitness landscape, the only place to go is down, which would be selected against. Of course the landscape is always shifting (due to large meteors or co-evolving competitors, etc.), but for some creatures, their fitness landscapes are considerably more stable and robust than others. Look at sharks and crocodiles....

[fossilnut2]

Cougar: those are some excellent points. Evolution 'just is'.

It's only humans who artificially distinguish life and non-life or organic and inorganic. They are all governed by the same properties of matter and energy. Complexity or the reverse are just perceptual overlay descriptions of states of matter and energy.
From a biological point of view for the most part life is not all that complex. It is only complex on the fringes...multicellular organisms. These make up a minutia of organisms. Life is mostly bacteria and similar life forms. Non-nucleus organisms are probably not more complex than they were 2 or 3 billion years ago and will stil dominate life 2 or 3 billion years from now.

[Platinum Rhymer]

http://asweknowit.ca/evcult/Complexity.shtml

Okay, it might not be an absolute rule but does evolution favor it?

[Quartermain]

I would say that evolution does not favor complexity. The simplest organisms have been the most successfull in terms of the longevity of species so that discounts any claim that evolution favors complexity. On the other hand to conclude that evolution favors simplicity also would not be true becuase despite the success of the simplest organisms evolution will inevitably result in more complex forms of life. That is part of the nature of evolution.

Consider that it only took one mutation in countless billions of trillions to result in a unique trait that allowed that species to branch off in a whole new direction. The nature of DNA is such that it never lost the traits it had previously. The organism added to its complexity.

An organism can never become simpler (in terms of function) than it already is. To do so would require a mechanism in nature that doesn't exist. The combination of mutation and natural selection can only result in organisms becoming more complex over time.

[CharlesEGrant]

Consider that it only took one mutation in countless billions of trillions to result in a unique trait that allowed that species to branch off in a whole new direction. The nature of DNA is such that it never lost the traits it had previously. The organism added to its complexity.
This is not true. Genetic information is frequently lost, otherwise the amount of DNA in organisms would increase monotonically over time, and this is not the case. As a specific example most mammals can synthesize vitamin C from other nutrients. The primates have lost this ability. If the environment changes so that a gene no longer confers a selective advantage then mutations to that gene will not have a deleterious effect. The process of genetic drift may eliminate the gene from the population.

[Bathcat]

Apart from discrete organisms, my understanding is that very complex ecosystems like the Amazon rainforest are more stable than simpler ecosystems like the Canadian tundra.

Given the opportunity -- ie climatic stability and sufficient water -- I might hazard a guess that ecosystems would evolve toward a condition of complex stability. But that's not really what the original poster asked, I think.

[SrK]

Cougar: those are some excellent points. Evolution 'just is'.


I think that we cannot consider evolution through the terms of "complex" or "simple" as those are definitions WE attach from our point of view. If we have never seen a bacteria, then it might look complex to us. Just an example of how subjective that definition can be.

We can consider evolution as the process of becoming efficient with what exists on a determined ecosystem.

Viruses may not have evolved that much, but their evolution is determined by the "needs" and their satisfaction. We can see the same situation if we evaluate other species, even those that where extincted, those species had needs that evolution did not had the time to fullfill during the time the specie existed with that need.

The species that continue to exist have reached the point of stabillity, which can be broken as new needs come across (such as shorter pregnancy time, faster growth, and a huge list of what else can be.) we can consider this as we see the horse's evolution, as we have the proofs of its ancesters and we can evaluate the needs they had at the time of their evolution and evolution's response trough time. (We need to take in count that IT DOES take time for evolution to be completed)

At that point, we can consider that evolution goes where needs make them go.


Sr.K.

[Kesh]

Evolution isn't a "thing" at all. It's just a process. In that sense, evolution favors nothing, as it's not a being that can favor.

In practice, complex systems tend to be better suited to survival, as they can handle more stresses without failing. The downside is that it also opens them to more potential stresses. Simple organisms can be adversely affected if their environment changes in small ways, but overall have become better suited to their current environment than a complex organism would be.

Think of it this way: a complex organism has more potential points of failure, but overall can withstand more varied environments. A simple organism is ideally suited for one environment, easily destroyed if moved to a new one or its environment changes drastically, but that is it's only major weakness.