by cantleave 26 Replies latest jw friends
a flat-out misrepresentation of the position of evolutionary biologists for over a century-Adam
okay cool you answered my first question. But how?
Adam keep it to 3 lines, I am rubbish at biology and have a short attention span this afternoon. Kate xx
Why is your long winded sentence more accurate that simply "survival of the fittest"?
I explained it already above: there's no guarantee that ONLY the fittest members WILL survive.
Broadly speaking, only those members who are capable of surviving a given selection pressure survive to pass on their genes to their offspring. Sounds like circular logic, but it's actually not.
In some cases, ALL members of a species will be wiped out if the selection pressure is too strong (eg large species of dinosaurs went extinct after a meteor hit the Earth, since none had the capability to survive the ensuing changes in the atmosphere which collapsed their food chain).
In some cases, ALL members of a species survive, if the selection pressures are weak (which is the normal case on Earth; changes are slow enough such that all members are well-enough adopted to their environment, and all survive).
In some cases, the best-adapted members are eliminated from the gene pool, simply due to their random bad luck (eg the fastest antelope is caught off-guard by the weakest lion who carries less-fit genes, due to it's random bad luck, and the lion's good luck).
Hence, SOTF is far too simplistic to withstand verification by actual observational studies which study how evolution actually operates "in the wild".
Adam
In some cases, the best-adapted members are eliminated from the gene pool, simply due to their random bad luck (eg the fastest antelope is caught off-guard by the weakest lion who carries less-fit genes, due to it's random bad luck, and the lion's good luck).
I've never really heard this before. Could you elaborate?
Most of the new species are often slight variations of existing ones where no one has noticed the specific features before.
Also, people shouldn't get the impression that the new ones discovered make up for the ones going extinct. They don't balance out.
A slight variation of a fish is nothing compared to losing the tiger.
Also, people shouldn't get the impression that the new ones discovered make up for the ones going extinct. They don't balance out.
Absolutely Simon. Of course with time diversity can in theory be restored by evolution, however it may require a mass extinction event to allow a suitable "restore point" for this to happen.
Hence, SOTF is far too simplistic to withstand verification by actual observational studies which study how evolution actually operates "in the wild".- Adam
Sorry you lost me at gene pools. In a species of dogs, the fittest dogs survive and create gene pools with genetic attributes, to me SOTF, is simple to the point an accurate deiscription, in order to be genuine one can add that at any time adhoc circumstances can interfere with SOTF. I don't get the big deal in using the term.
It is taught in schools at GCSE level biology in the UK, but the big bang theory is not, hence SOTF phrase must have substance and I would have thought it was reliable.
Which evolutionary biologist that has been published says the term cannot be taught in schools anymore?
The Big Bang is not taught in U.K schools ?? do you mean they do not cover the start of the Universe, or that they teach some alternative ? I find both propositions strange.
I thought Adam's answer above was excellent. Like nearly all short hand expresseions, the Big Bang being one of them, they are usually a form of Journalese, a phrase that lazy people use rather than being accurate.
And, as Adam has showed, such phrases tend to shroud the truth, not illuminate it, they are hardly "reliable".
It has been amazing how many new species have been discovered recently, especially the bigger mammals!
Kate - Survival of the fittest isn't wrong but it is easily misunderstood. Creationists go out their way to misunderstand it.
Natural selection is better understood at the level of the gene than the speices or even the individual.
Survival of the fittest is a shorthand for something like the following...
Genes that are good at working in partnership with other genes in the same gene pool for building bodies that are successful at passing on those genes to the next generation will tend to prosper at the expense of other alleles that are less well suited to the task.
Adam said-In some cases, the best-adapted members are eliminated from the gene pool, simply due to their random bad luck (eg the fastest antelope is caught off-guard by the weakest lion who carries less-fit genes, due to it's random bad luck, and the lion's good luck).
Zound asked- I've never really heard this before. Could you elaborate?
Pretty simple, really: random chance plays a role in which members survive, as well.
The problem with the SOTF meme is that evolution would operate that way, if eg all the antelopes were lined up at a starting gate, and all the lions were at their starting gate 300 yds away, and there were referees to ensure that only the fastest antelopes were allowed to survive, and only the fastest lions were allowed to eat the slowest and least-fit antelopes, so the lions didn't die of starvation. Nature isn't that 'clean', and there are no referees.
What happens in actuality is that on average, those members who are better-adapted by possessing the traits which allow them to survive will have a statistically-greater chance reaching reproductive age vs their co-horts to pass on their genes to offspring. The difference is often very slight, but it's enough such that those members who are genetically-endowed with skills to survive will do so, overall, but it's no guarantee that any individual member will survive, since there is an element of chance to survival. Often, random mutations lead to harmful changes, such that the fetus isn't viable and is spontaneously aborted; that's often a chance event, as well, and generally the mutation must occur in the gametes (and not somatic cells) in order for the trait to be passed onto subsequent generations.
Many newbies to evolution don't want to accept that, or are somehow threatened by it, since it threatens their nice and tidy concept that evolution is all about "onwards and upwards" (which SOTF tidily suggests), but the reality is that natural selection is rarely "clean", and doesn't care if us humans approve of it's methods or not! The reality of evolution having rough edges to it actually helps explain other things, eg why species often end up going extinct (due to maladaptations, etc), or how conditions like sickle cell anemia or Huntington's Chorea can be develop where they didn't exist before, and can in turn be resiliant to elimination via natural selection.
Bottom line is, there is no guarantee of survival OR reproductive success OR perfect health.
SOTF relies on the "competitive exclusion principle", which has been challenged by findings such as these:
http://phys.org/news135573322.html
Adam
