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
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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 …
- the Pythons in the Florida wetlands
- Rabbits in Australia (which shows that this can be a problem even with herbivore competition amongst each other)
- Asian Carp introduced into various American waterways…
- Feral pigs… in Florida and a few other places…
- Zebra Mussels…
- European Green Crabs…
- Brown Tree Snake in Guam wiped out 12 out of the 22 native bird species…
- 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…
- 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 …
NOTE:
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!