Invasive species and survival of the fittest spin-off

(George Brooks) #1


Roger, You think it’s hypothetical? I have posted on the REALITY of it several times on these boards. Inter-species competition is ENVIRONMENTAL !!! And it can make all the difference.

Here are links to some of my posts on the Terror Birds!

This posting has images comparing the size of humans with Terror Birds:

[Click on the link above to see a terrifying image of Evolution!]

And this link (above) is to the post where it is discussed that Terror Birds were the top predators of South America! They were virtual LIONS on the plains of the southern continent. But then North America and South America slammed together at Panama… and the REAL canines (wolves) and felines (giant cats) started to infiltrate South America.

While Terror Birds were perfectly capable of defending themselves from the intruders… the intruders seemed to be better able to feed off the local fauna … and the Terror Birds were starved out. It’s a good thing too … Terror Birds probably would have eliminated any Asiatic humans that crossed into Terror Bird territory.

The irony of episodes like this is if wolves and cats and terror birds had all evolved together, each gene pool would have had a greater opportunity to find a balance in rivalry with each other. But when two different predators are allowed eons of separate evolution, their sudden meeting in a new land can sometimes quickly sort out into one gene pool simply disappearing.

The link to the article below actually focuses on that point specifically - - by talking about how isolated species on islands represent the highest number of extinctions!

Invasive species are the greatest cause of extinction

Published on: Sunday, 28 June, 2015
"Of 217 mammals and birds that have died out, nearly all were on islands"

This writer would probably even CONTRADICT your emphasis, Roger !!!

“Human beings have been causing other species to go extinct at an unnatural rate over the past five centuries, a new study has confirmed. . . . .So it is vital to understand how we cause extinctions. And here the study is dangerously wrong. It says that “habitat loss, overexploitation for economic gain, and climate change” are the main factors and that “all of these are related to human population size and growth, which increases consumption (especially among the rich)”.”

“Inexplicably, they have left out the main cause of extinctions over the past five centuries: invasive species. The introduction by people of predators, parasites and pests, especially to islands, has been and continues to be far and away the greatest cause of local and global extinction of native fauna… . . Over the past 500 years, we know of 77 mammal species (out of about 5,000) and 140 bird species (out of about 10,000) that have gone totally extinct. There may be a handful more we do not know about…”

“Of those 217 species of bird and mammal, almost all lived on islands — if you count Australia as an island — and just nine on continents: Bluebuck antelope, Algerian gazelle, Omilteme cottontail rabbit,Labrador duck, Carolina parakeet, slender-billed grackle, passenger pigeon, Colombian grebe and Atitlan grebe.”

Other Examples of inter-species competition …

  1. the Pythons in the Florida wetlands
  2. Rabbits in Australia (which shows that this can be a problem even with herbivore competition amongst each other)
  3. Asian Carp introduced into various American waterways…
  4. Feral pigs… in Florida and a few other places…
  5. Zebra Mussels…
  6. European Green Crabs…
  7. Brown Tree Snake in Guam wiped out 12 out of the 22 native bird species…
  8. Nile Perch (typically 400 pounds in size) was introduced into Lake Victoria (Africa) wiping out 100 species of fish that couldn’t figure out a way to live WITH the species…
  9. The predatory snail, Euglandina rosea, introduce from southern American states to Hawaii to fend off a DIFFERENT predatory snail, have also wiped out desirable snails in the isolated islands…

I think this should be enough to point out that my so-called hypothetical example is not hypothetical in the least …


OH, Roger … I forgot to mention one thing … I suppose I don’t have a problem with you man-handling the phrase “Survival of the Fittest”. It is a sloppy kind of term.

But when you try to exclude whole categories of Environmental elements that include diverse facets of inter-species competition … you seem to just be seeking cover behind a phrase like “Survival of the Fittest”. Because the phrase you and I both prefer is NATURAL SELECTION - - and that phrase applies to inter-species rivalry quite adequately!

What Changed with Sin?
What Changed with Sin?
(Roger A. Sawtelle) #2


As I said the invasion of an invasive species is different from evolution, which is the creation of a new species.

(George Brooks) #3

Yes… it is, @Relates

But new speciation is TRIGGERED when once dominant life forms disappear from the scene.


I don’t know how you could conclude that @gbrooks9 is attempting to equate evolution with the invasion of a new species. It’s clear that his argument is that the invasion of one species can result in speciation which is a survival response. The invasion by a newly introduced species disrupts equilibrium. There is no need for adaptation in an environment of equilibrium.

(George Brooks) #5


Roger has a number of rules for what God is willing to do and what God is NOT willing to do. And he has rules for what he said should be ALLOWED to be discussed by evolutionists.

Once you get used to all his rules … everything will be fine…

(Roger A. Sawtelle) #6


George and fmiddel,

We were not talking about evolution in general. We were talking about the place of conflict as the basis of the Survival of the Fittest.

Out of the blue George brings up a hypothetical example of an invasive species taking over the place of lions of all things. This is not evolution. Evolution is where a new species evolves as the result of genetic changes in response to ecological change. When an invasive species takes over a native species is displaced. No new species is formed.

Yes, it is true that new species might appear, but that is not required, and it is not caused by intra-species conflict and the survival of the fittest.

I do not mind discussing anything that is germane to the discussion, which was about original sin and not about biology, except violence as a part of evolution.

(George Brooks) #7


Yes, yes, and another yes, Roger. However, Intra-species conflict is how a single genetic modification spreads throughout a gene pool. It’s pretty much the DEFINITION of gene pool evolution. If the gene pool doesn’t display changes (due to SUCCESSFUL competition) … then there is NO evolution.

Anyone who has ever attempted to date the “pretty girl in class” by buying a sports car knows full well that the game is INTRA-SPECIES rivalry …

And during World War II … when the British men suddenly found themselves competing against “Invasive Americans” to date and mate the women of England … you can see that ANY rivalry by a newly invading creature (within or outside the normal “kind”) puts pressure on the population’s gene pool.

I understand that my example of the British male is not about Inter-Species competition. But I could just as easily be talking about the Elk in American preserves that were causing great damage to the riverbank ecosystem because they alpha adults were bringing their herds into the wide open areas of their territory - - where grazing and water was plenty… and predators were not.

Then humans brought wolves back!

And suddenly, the herds once again avoided the easy life of the river basins… because they were too easy to be hunted by the wolves…

Competition comes from EVERYWHERE …

(Larry Bunce) #8

Migration of new species into an area accounts for the relative lack of intermediate forms in the fossil record. Speciation generally occurs in an isolated population, so the intermediate forms would be located in a limited area, and be less likely to become fossilized. Any new stress on an existing population can cause evolutionary change, whether from environmental factors or the sudden appearance of a new species. if the stress is too great, the old form will become extinct, but with just the right amount of stress the two populations can co-evolve, possibly creating several new species. It seems that most evolutionary adaptations have an up and a down side, so that it is impossible to predict which side might win. Competition can also be indirect, where the new species decimates the food supply of the previously dominant species.
Darwin originally used the term “natural selection” in describing evolutionary change. Someone pointed out to him that this term implied a Selector, so that it might be more scientific to borrow Herbert Spencer’s term “survival of the fittest.” That term was then criticized as being a truism, since obviously the survivors would survive, and also because the word ‘fittest’ implies the strongest, when many other qualities can make an organism better able to survive.
The early mammals couldn’t compete directly with dinosaurs, but by remaining small and hiding from them, they could survive until the dinosaurs died out.

(Roger A. Sawtelle) #9

However, Intra-species conflict is how a single genetic modification spreads throughout a gene pool. It’s pretty much the DEFINITION of gene pool evolution. If the gene pool doesn’t display changes (due to SUCCESSFUL competition) … then there is NO evolution.


You do not need to shout to make a point, nor does shouting make something true.

Actually you are mistaken. It is not conflict that spreads a new allele. It is adaption to the environment which allows a new allele to survive and thrive so the new modification spreads and becomes dominant.

(George Brooks) #10
  1. I do not capitalize to shout… I capitalize to EMPHASIZE … If I capitalize a whole sentence… then I’m shouting.

  2. I think you are splitting hairs over linguistics. When a male with a huge head of hair competes for a female in a tribe full of bald men… there is plenty of conflict in the process. And if the male with a huge head of hair isn’t able to defend himself as well as the bald men … his genes will probably disappear DESPITE his popularity with the females…

(Roger A. Sawtelle) #11


You emphasize with bold and italic.

What you need to do is stop thinking about evolution as human interactions and try to think in terms of biology,

(George Brooks) #12

To make that sentence correct @Relates, you need to say “I emphasize …” because that’s what YOU do. It’s not what I do.

Biology knows no limits for how conflict is expressed. If you were more familiar with patterns of Alpha males and females in populations of felines and canines you wouldn’t be writing what you write.

You make for an interesting case study, Roger. Because you are the first proponent of BioLogos (you are a proponent, right?) that uses rather unusual RELIGIOUS ideas to justify your pro-evolution views.



But you should…

(Roger A. Sawtelle) #14


Wrong again. I am a critic of BioLogos.

I really do not think that my understanding of the Logos is that unusual. Please do not confuse religion with Christian theology.

I am a critic of Darwinian evolution that you seem to support, but I am not against evolutionary change which many Christians who are not evangelicals also support.


Thank you.

(George Brooks) #15



I don’t know any non-Evangelical Christians, who support Evolution but REJECT the idea that evolution involves (to a greater or lesser degree) conflict WITHIN and BETWEEN species.

You may be unique on the planet Earth in your specific beliefs on this.

(George Brooks) #16


Roger, I really don’t get you.

There is symbiosis… and there is competition. They are 2 ends of the same gradient… and depending on the circumstances, one species might favor one side of the gradient or the other.

We KNOW this … because we can identify PARASITES that kill… and sybmiotes that help keep their partners alive.

Ever since you told me that God JUST DOES NOT intervene in genetic molecules I have found your viewpoint to be more than just a little non-responsive to evidence.

Job tells us that God guides whole bolts of lightning … and you say that he won’t guide a single cosmic ray.

I just don’t get you any more.

(Roger A. Sawtelle) #17


Because someone challenges your pet idea about cosmic rays, you don’t get him anymore.?!

Job is interesting, but hardly conclusive scientific evidence, which is what we are talking about here.

Yes, parasites kill for food, and so do humans. Humans harvest all sorts of plants and animals for food, and yet we have a symbiotic relationship with them, as do most prey and predators.

Competition between prey and predators is not for scare resources, because lions cannot eat the grass that zebras eat, nor do zebras eat the zebras or other prey lions eat. They need each other, which is what symbiosis is about, and conflict is not.

That is the way God ordered the Creation so all things work together in harmony, which some occasional exceptions that prove the rule. I think that is what YHWH was saying in Job. YHWH ordered the universe, so YHWH does not need to micromanage it.

(George Brooks) #18

Roger, you just can’t EXCLUDE viable elements in the race to spread genetic information far and wide.

Zebras don’t eat Zebras… right. But if a new predator shows up … and is better at eating Zebras than lions are … Lions will either change food sources or die out.

(Roger A. Sawtelle) #19


Survival of the Fittest is about intra-species struggle. You are bringing up a inter-species struggle for survival, and an invasive species at that. Since the example you give is very hypothetical, it is hard to comment on.

However it is true that there are invasive species which do change the environment and thus offer a challenge to existing species. This fits in very well with ecological natural selection, but not with the traditional Survival of the Fittest point of view…

(Roger A. Sawtelle) #20


Why is this an issue? Science is supposed to be based on facts, rather than popular opinion, right?

Please give me the scientific facts as to why I am wrong, not a lot of bluster.