Question about evolution

Mouse plagues in Australia is an extreme example. Yet, comparable mechanisms are causing high population peaks in other systems. I apologize that the list of examples below is long but I hope it is enough to show that this kind of things happen around the globe.

In dry areas, population peaks are mainly related to the amount of high quality food. After rainy periods, increasing amount of food increases offspring production and predation is not able to prevent the population increase. The key species involved are house mice in Australia, elsewhere other species that are called ‘mice’ or ‘rats’. Even the Bible includes information of at least two small rodent plagues.

In tundra, the key species are lemmings. At least some lemming populations are known to have ‘boom-crash’ dynamics, where reducing predation and accumulating food produce high lemming peaks. The peaks end (crash) after much of the high quality food has been consumed.

In Europe, the key species with high-amplitude oscillations are voles. The height of the peaks depends on the availability of high quality food and the composition of predator assemblages. In natural meadows, peak densities are usually around 300-400 voles per hectare. In agricultural fields with perennial crops of high-quality fodder the peak densities may be >1000 voles per hectare. During extreme peak years, there have been reports of densities up to 10’000 voles per hectare. If I remember right, one book listing such peaks in Europe is the ‘Voles, mice and lemmings’ by Charles Elton. It’s an older book but there are reports of vole plagues after that. I have somewhere a copy of a newspaper article reporting a devastating vole plague in Spain. In Finland, voles damage millions of tree saplings during high peak years, causing economical damage in millions of euros.

In Canada and Alaska, the key species is the snowshoe hare and small rodents play just a minor role. There are peaks of snowshoe hares but I have not heard of large vole or mice peaks in that area. Anyway, there are high peak densities, although not mice peaks.

This is not a place for a longer review, so I stop the list here. Although the height and visibility of the peaks depend on the system, the mechanisms producing these eruptions are comparable.

When I told about the chaotic population fluctuations, I misunderstood your use of the expression ‘balance of nature’. I told about chaotic fluctuations just to show that the systems are anything but static. Only later I read that your use of the ‘balance of nature’ does not mean static.

Chaotic fluctuations means population fluctuations with ‘strange attractors’. They are fluctuations where the fluctuations strongly depend on initial conditions; you cannot predict the future accurately, unless you have perfect knowledge of initial conditions. The same thing as with weather.

Well, we use the words ‘symbiosis’ and ‘coexistence’ in a different way. For me, they are not synonymes.

The population oscillations are a consequence of selfish behavior of consumers in a plant-herbivore-predator system.

With selfish behavior I mean that the actions of individuals are based on the interests of themselves, including the survival of their offspring. They do not consider the future of populations, species or communities.

Maybe I misunderstand what you mean but not all ecologists think in terms of ecological niches. I don’t.

I’m not sure what definition of ecological niche you use. Probably the Eltonian niche as Elton wrote about the place of species in their system ( I don’t remember exactly what words he used).

I prefer the definition by Hutchinson. Crudely, this definition describes ecological niches as properties of species, rather than their place in ecological systems. The fundamental niche describes the tolerance ranges of species in n-dimensional space - in what kind of conditions the species can live. The realized niche is the fundamental niche ± changes caused by interspecific interactions - the species does not live in all places where abiotic conditions would be tolerable because interspecific interactions exclude it from certain areas.

Just because words have a similar meaning prefix does not mean that the words themselves mean the same thing.

I’ll give you a pair of counterexamples that coexist: two rocks can coexist as well as two brothers. Does that mean they are symbiotic?

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@jstump

  1. How can the actions of mice be based on interests of themselves, when they cannot think? Of course they do not consider the future of populations, species, or communities, because they cannot think. They also do not consider the future of themselves, because they cannot think.

  2. If animals such as mice do not act out of thought, how do the act? They act out of instinct, or maybe memes. I think that instincts are conditioned responses. When an animal does something that works, that benefits it, it receives a positive response, that encourages it to repeat that action. In that sense instincts are learned.

Memes however if I understand them properly are not learned. Memes are directly connected to genes, which are not based on experience. That most likely why Dennett does not think humans have freewill. As Dawkins said, we are controlled by our DNA. The whole concept of memes bypasses the brain and is wrong. Our DNA certainly influences our behavior, it is the basis of our basic needs, but it does not control our behavior or the behavior of other biota.

  1. When we think about survival of the fittest/selfish gene we usually are thinking about the relationship between predator and prey, which are different species, but that is Wrong, because prey and predator are NOT competing for the same resources. It is zebras that would be competing for grass and lions that would competing for meat, BUT they aren’t. .

If survival of the fittest were true than all other humans would be our natural enemies because we would be in a life and death struggle with each other for survival.

  1. The question is not Whether biota are naturally selfish or cooperative? The question is about the character of the Creation. Is it basically good or evil? It is not good if it is basically chaotic which deprives it of its basic freedom. It is not good if it is based on conflict that sets every biota against everyone else.

  2. Symbiosis is the system or process that God/nature uses to keep all of the biota in balance with each other and the environment, so it can live in stable harmony… When one aspect of the environment changes, biota must adapt or go extinct… This is how evolution takes place. Physical change creates environmental change, which creates evolutionary change.

Two people are climbing two different mountains. In similar circumstances, one dies and the other doesn’t because the latter was more fit or better prepared. Does that mean they were natural enemies?

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My response to this definition of ecological niche is this. Is this what modern science has become? Taking clear, understandable words and ideas and transforming them into vague. bloodless, elitist terms. No wonder so many people are turned off by science.

The faults of science do not justify this distrust. Two wrongs do not make one right, even though survival of the fittest somehow believes that much conflict creates basic harmony. Scientists are not always innocent in this area. A great scientist like Lynn Margulis recognized that even YEC had reasons to question evolution, and many evolutionists never forgave her for this.

Could it be that you are misconstruing other things like you misunderstood definitions and concepts as illustrated above.

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Hutchinsonian niche is not a new concept. He published the definition in the year 1957.
It is widely used because it is less vague than the alternatives and can therefore be used more easily in mathematical approaches.

There are those that prefer other niche concepts, Grinnellian or Eltonian. In my opinion, these definitions are more vague, although they have their benefits. If Eltonian niche is simply used to mean relations with food and enemies, it can be used in research by focusing just on these interactions.

This is one more example that terms do not mean the same for all. Even professionals may use the same words with different contents. It’s better to define what we mean than assume that the term means the same for all.

I have to say that my logic does not fully follow these statements.

Is the definition of ‘free’ or ‘bad’ that something is not chaotic?

Is the symbiosis something that keeps all biota in balance with each other even if the environment changes?
It is well known that during succession or if the environment changes otherwise, species are replaced with other species. How can a biota be in balance with each other if not even the species (‘each other’) stay the same?

This is an interesting question because it questions the ability of animals to think.
Are humans the only creatures that can think?
What is thinking?

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Intentionality.

Thank you, @Klax.

As I said, other animals can learn from experience and observation, which can be thought of as a type of thinking, but that is not what we normally think of as thinking which is an intentional, deliberate act, which is not based on an immediate stimulus. We are able to store memories and ideas, which we can explore whenever.

Do you know of anyone who thinks that dogs love or hate like humans?

Free means not predetermined. If I am predetermined, I am not good or bad, the person or thing that predetermined me is good or bad.

Chaos, the real chaos, not the fake chaos of Chaos Theory, is totally unpredictable. It is the opposite of predetermined. It is bad because humans cannot plan around it, as it would seem we could around something predetermined, if we know that it is predetermined. As I have said before God does not predetermine.

Think gravity. Does gravity disappear when a space ship leaved the earth’s gravitational field and enters the gravity of Mars? Gravity keeps things in balance usually. Symbiosis keeps biota together with the environment usually, except when the environment crashes from the overabundance of stress.

From personal experience I’d say they are our superiors where love is concerned but are greatly inferior to us when it comes to hating.

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This is an interesting idea but I have difficulties in understanding it.

Gravity is a force by which all things having mass or energy are attracted to one another. If we replace the center of the mass attracting other bodies by gravity with the word ‘attractor’, your analogy seems to suggest that, as long as the system has an attractor, it is in balance of nature. Does it matter what kind of attractor the system has?

The claim of symbiosis keeping biota together with the environment seems to be close to the idea of Grinnellian niche where the concept of niche is tied to the concept of habitat - species are adapted to certain kind of environment and that kind of environment (habitat) attracts species that are adapted to it. If the environment changes, for example trees replace grassy vegetation, the attractor changes. Some of species may stay but most are replaced by other species. Yet, you claim that the balance of nature is not affected; biota is in balance before and after the change and also during the change.
Did I understand it right?

‘environment crashes from the overabundance of stress’. I need a bit more explanation to understand this.
What is a crash of environment?
What kind of stress do you mean?

I noticed that in an earlier comment, you lifted up the name of Lynn Margulis. In addition to the other things she published, she was a supporter (or co-developer) of the Gaia hypothesis. Your strong emphasis on a general balance of nature through symbiosis seems to come close to the Gaia hypothesis. Do you think that the biological systems of earth form a single system that is self-regulatory?

A perfectly valid method for grasping at the truth, and I happen to agree with your conclusion. From personal experience myself. :wink:

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First of all you described the old view of Newtonian gravity of attraction at a distance. The Einsteinian current understanding is that gravity is caused by mass/energy bending space/time.

The effect is still basically the same. Bodies have a mutual relationship with each other as the.earth and its moon. The gravity of the earth causes its moon to revolve around it. The gravity of the moon causes our oceans to have tides. Predators and prey have a mutual relationship with one another that keeps them in a dynamic balance, which is not static, but stable within given limits.

Why do you keep trying to make me say that to say that science is static? Do I seem that stupid or ignorant?

I would think that is is very similar, which makes me wonder why you seem to think that my understanding was something totally off the wall rather than a valid scientific view.

NO. Symbiosis tends to keep elements in nature in balance. When there are too many predators some may migrate to other niches or some might die because of lack of prey. Too many prey attract more predators. The symbiosis tends to be self-correcting, but at times the system does not self-correct so radical changes are made so a new balance is determined.

Symbiosis in an abundance causes predators to kill more prey… Symbiosis in an a dearth causes predators kill fewer prey. Thus causing population cycles as in the paper you cited…

[/quote]

“Population cycles that persist in time and are synchronized over space pervade ecological systems, but their underlying causes remain a long-standing enigma.(1-10)”
[/quote] paper by Hanski et al. 1993 in Nature 364: 232-235.

This statement directly from the only scientific paper that you have cited is an excellent description of “symbiosis” even to saying “their causes remain a along-standing enigma.” It is backed by many citations (11) !

I quoted Dawkins using symbiosis in the Selfish Gene. You said Grinnell had a similar understanding ecological niche. I cited this scientific example of stability in the midst of change.

Do I think that all biology is related and is based on common natural laws? Of course. Don’t you?

I asked the questions because I wanted to understand. Thanks for answering.

It is obvious that we use the same terms but with different meaning, look the questions from different viewpoints and have different basic assumptions. This leads to a communication problem - it’s difficult to understand.

I can only conclude that we disagree and further discussion is not likely to change that.
God bless you.

I take it that you do not agree with Lynn Margulis that the biosphere is essentially one system that takes many forms and that it has worked for these millions of years because it is interdependent and self-correcting. I suggest to you that if she and the many others like me who think the same way are not correct and if scientists like your self do not find better ways of working With symbiosis, rather than work against it, we humans are surely doomed.

We are doomed because our selfish needs first, not the need for God’s love and God’s people. Do not think we can turn to God at the last minute and plea for help. God is not interested in saving people who are only asking for help because they got caught, not because they repent of their selfishness that they have justified by the ideology of the Selfish Gene.

You are right. This is more than a scientific question. This is a moral, philosophical, and theological question, which makes it more important not less. This is the kind of dialog that I thought BioLogos was meant to encourage. I hope that you and others will not run away from it now.

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