Evolution

[The Doctor]

Right, it concerns me how wrong some people on this forum are, so some education is in order.

Let's start with some definitions:

Theory: A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of knowledge that has been repeatedly confirmed through observation and experiment. (National Academy of Sciences definition).

Now then, before I delve into the evidence for it, let's clear up a few misunderstandings:

1. Evolution doesn't explain how life came from dead matter.

This is like complaining that gravity doesn't explain why the earth is spherical. Evolution has only ever been concerned with explaining variation in life we see, it has never troubled itself with the origins of life. That is the area of abiogenesis - not of evolution.

2. It's just a theory.

See the definition above. A theory in scientific terms is not a guess, it is the highest level of validity achievable in science.

3. Mutations are never beneficial.

Not at all, if you say that then by extension you deny the existence of MRSA. Methicillin-resistant Staphylococcus aureus is a variant of the S. aureus bacterium that, through mutation, gained resistance to the penicillins (which includes Methicillin, the final antibiotic that was effective on it, hence the name). Those mutations are very much beneficial to S. aureus.

4. Micro-evolution is fine, but macro-evolution has no evidence.

Macro-evolution is just micro-evolution over a longer time period. It's like saying "hours exist, but years don't".

So then, one of the first claims I see is that there's no evidence of speciation ever occurring - this is a lie - I've taken the following section from Talk Origins (a very good website for clearing up misconceptions about evolution):

5.1 Speciations Involving Polyploidy, Hybridization or Hybridization Followed by Polyploidization.

5.1.1 Plants

5.1.1.1 Evening Primrose (Oenothera gigas)

While studying the genetics of the evening primrose, Oenothera lamarckiana, de Vries (1905) found an unusual variant among his plants. O. lamarckiana has a chromosome number of 2N = 14. The variant had a chromosome number of 2N = 28. He found that he was unable to breed this variant with O. lamarckiana. He named this new species O. gigas.

5.1.1.2 Kew Primrose (Primula kewensis)

Digby (1912) crossed the primrose species Primula verticillata and P. floribunda to produce a sterile hybrid. Polyploidization occurred in a few of these plants to produce fertile offspring. The new species was named P. kewensis. Newton and Pellew (1929) note that spontaneous hybrids of P. verticillata and P. floribunda set tetraploid seed on at least three occasions. These happened in 1905, 1923 and 1926.

5.1.1.3 Tragopogon

Owenby (1950) demonstrated that two species in this genus were produced by polyploidization from hybrids. He showed that Tragopogon miscellus found in a colony in Moscow, Idaho was produced by hybridization of T. dubius and T. pratensis. He also showed that T. mirus found in a colony near Pullman, Washington was produced by hybridization of T. dubius and T. porrifolius. Evidence from chloroplast DNA suggests that T. mirus has originated independently by hybridization in eastern Washington and western Idaho at least three times (Soltis and Soltis 1989). The same study also shows multiple origins for T. micellus.

5.1.1.4 Raphanobrassica

The Russian cytologist Karpchenko (1927, 1928) crossed the radish, Raphanus sativus, with the cabbage, Brassica oleracea. Despite the fact that the plants were in different genera, he got a sterile hybrid. Some unreduced gametes were formed in the hybrids. This allowed for the production of seed. Plants grown from the seeds were interfertile with each other. They were not interfertile with either parental species. Unfortunately the new plant (genus Raphanobrassica) had the foliage of a radish and the root of a cabbage.

5.1.1.5 Hemp Nettle (Galeopsis tetrahit)

A species of hemp nettle, Galeopsis tetrahit, was hypothesized to be the result of a natural hybridization of two other species, G. pubescens and G. speciosa (Muntzing 1932). The two species were crossed. The hybrids matched G. tetrahit in both visible features and chromosome morphology.

5.1.1.6 Madia citrigracilis

Along similar lines, Clausen et al. (1945) hypothesized that Madia citrigracilis was a hexaploid hybrid of M. gracilis and M. citriodora As evidence they noted that the species have gametic chromosome numbers of n = 24, 16 and 8 respectively. Crossing M. gracilis and M. citriodora resulted in a highly sterile triploid with n = 24. The chromosomes formed almost no bivalents during meiosis. Artificially doubling the chromosome number using colchecine produced a hexaploid hybrid which closely resembled M. citrigracilis and was fertile.

5.1.1.7 Brassica

Frandsen (1943, 1947) was able to do this same sort of recreation of species in the genus Brassica (cabbage, etc.). His experiments showed that B. carinata (n = 17) may be recreated by hybridizing B. nigra (n = 8) and B. oleracea, B. juncea (n = 18) may be recreated by hybridizing B. nigra and B. campestris (n = 10), and B. napus (n = 19) may be recreated by hybridizing B. oleracea and B. campestris.

5.1.1.8 Maidenhair Fern (Adiantum pedatum)

Rabe and Haufler (1992) found a naturally occurring diploid sporophyte of maidenhair fern which produced unreduced (2N) spores. These spores resulted from a failure of the paired chromosomes to dissociate during the first division of meiosis. The spores germinated normally and grew into diploid gametophytes. These did not appear to produce antheridia. Nonetheless, a subsequent generation of tetraploid sporophytes was produced. When grown in the lab, the tetraploid sporophytes appear to be less vigorous than the normal diploid sporophytes. The 4N individuals were found near Baldwin City, Kansas.

5.1.1.9 Woodsia Fern (Woodsia abbeae)

Woodsia abbeae was described as a hybrid of W. cathcariana and W. ilvensis (Butters 1941). Plants of this hybrid normally produce abortive sporangia containing inviable spores. In 1944 Butters found a W. abbeae plant near Grand Portage, Minn. that had one fertile frond (Butters and Tryon 1948). The apical portion of this frond had fertile sporangia. Spores from this frond germinated and grew into prothallia. About six months after germination sporophytes were produced. They survived for about one year. Based on cytological evidence, Butters and Tryon concluded that the frond that produced the viable spores had gone tetraploid. They made no statement as to whether the sporophytes grown produced viable spores.

5.2 Speciations in Plant Species not Involving Hybridization or Polyploidy

5.2.1 Stephanomeira malheurensis

Gottlieb (1973) documented the speciation of Stephanomeira malheurensis. He found a single small population (< 250 plants) among a much larger population (> 25,000 plants) of S. exigua in Harney Co., Oregon. Both species are diploid and have the same number of chromosomes (N = 8). S. exigua is an obligate outcrosser exhibiting sporophytic self-incompatibility. S. malheurensis exhibits no self-incompatibility and self-pollinates. Though the two species look very similar, Gottlieb was able to document morphological differences in five characters plus chromosomal differences. F1 hybrids between the species produces only 50% of the seeds and 24% of the pollen that conspecific crosses produced. F2 hybrids showed various developmental abnormalities.

5.2.2 Maize (Zea mays)

Pasterniani (1969) produced almost complete reproductive isolation between two varieties of maize. The varieties were distinguishable by seed color, white versus yellow. Other genetic markers allowed him to identify hybrids. The two varieties were planted in a common field. Any plant's nearest neighbors were always plants of the other strain. Selection was applied against hybridization by using only those ears of corn that showed a low degree of hybridization as the source of the next years seed. Only parental type kernels from these ears were planted. The strength of selection was increased each year. In the first year, only ears with less than 30% intercrossed seed were used. In the fifth year, only ears with less than 1% intercrossed seed were used. After five years the average percentage of intercrossed matings dropped from 35.8% to 4.9% in the white strain and from 46.7% to 3.4% in the yellow strain.

5.2.3 Speciation as a Result of Selection for Tolerance to a Toxin: Yellow Monkey Flower (Mimulus guttatus)

At reasonably low concentrations, copper is toxic to many plant species. Several plants have been seen to develop a tolerance to this metal (Macnair 1981). Macnair and Christie (1983) used this to examine the genetic basis of a postmating isolating mechanism in yellow monkey flower. When they crossed plants from the copper tolerant "Copperopolis" population with plants from the nontolerant "Cerig" population, they found that many of the hybrids were inviable. During early growth, just after the four leaf stage, the leaves of many of the hybrids turned yellow and became necrotic. Death followed this. This was seen only in hybrids between the two populations. Through mapping studies, the authors were able to show that the copper tolerance gene and the gene responsible for hybrid inviability were either the same gene or were very tightly linked. These results suggest that reproductive isolation may require changes in only a small number of genes.

As you can see, we've observed speciation a number of times.

Now then, my absolute favourite thing to drag out in this subject is ERV's. Endogenous retroviruses are the remnants of retroviruses that inserted themselves into the genome of an animal. Due to the size of the genome, it is statistically impossible for two people to share an ERV unless they have a common ancestor. This is how DNA tests work. In other words ERV's can show common ancestry between two people. Now take that back an extra few million years - it can show common ancestry between two species. If common ancestry is present then the two species must be decended from one, or in other words, speciation occurred to form the two separate species.

So, let's look at the human genome, and contrast it with the genome of the chimpanzee (believed to be our closest relative). This was researched and published in Gene (biology papers) - http://www.ncbi.nlm....ubmed/10773466.

Unfortunately, only the abstract is available to non-academics - however the nice chaps at freerepublic have summarised the key part (for my point) for us: There are at least seven different known instances of shared ERVs between chimps and humans... i.e. ERVs which are the identical viral DNA inserted into the identical spot of the genome. 100% of all chimps and 100% of all humans have these same ERVs. This is only possible if 100% of all chimps and all humans are descended from the single individual that had these original infections.

Or to put it simply - as those shared ERV's exist, and are shared by 100% of both species, both species must have had a common ancestor.

tl;dr - speciation observed numerous times, ERV's are conclusive proof of common ancestry, which is further evidence for evolution.

any questions?

[Charl91]

I didn't even realise anyone on this forum was denying the existence of evolution?

[foxfanazer]

I didn't even realise anyone on this forum was denying the existence of evolution?

I don't know. Some of these Cardiff fans that come on here make me wonder

[The Doctor]

I didn't even realise anyone on this forum was denying the existence of evolution?

You've not been paying attention to El Empty then:

[Captain...]

I don't know. Some of these Cardiff fans that come on here make me wonder

But surely they are proof, evidence of what we have evolved from, or are devolving into depending on your point of view.

[foxfanazer]

But surely they are proof, evidence of what we have evolved from, or are devolving into depending on your point of view.

good point

[Haydos]

Probably getting a bit wound up over El Empty's WUMing/complete ignorance.

Besides, people are wont to believe what they like blindly, plenty do and rarely will they change even with arguments and facts presented to them.

[Uncle Phil]

Nick Lanes Life Ascending, The 10 Great Inventions of Evolution is a great read for anyone wanting to know more.

[Charl91]

You've not been paying attention to El Empty then:

http://www.foxestalk...20#entry2511865

http://www.foxestalk...20#entry2511928

http://www.foxestalk...20#entry2511937

So when you said "some people" you really meant "one person"?

[Danizen]

So when you said "some people" you really meant "one person"?

Classic straw man argument from The Doc. It could have been a decent thread, as well.

[Captain...]

I always find the story of rabbits in Australia to be a clear succinct example of evolution in action:

European rabbits were introduced into Australia in 1859 by a wealthy Victorian grazier for hunting, and soon became a major pest species.

CSIRO's initial release of myxoma virus in 1950 led to a dramatic reduction of Australia’s rabbit population.

The virus killed 99.8 per cent of rabbits that caught the infection. It was the world's first biological control of a pest mammal.

Myxomatosis is a disease of European rabbits caused by myxoma virus.

Today many wild rabbits in Australia are quite resistant to infection

Even if it was man made evolution, a dramatic change in environment resulted in a genetic resistance in rabbits to myxomatosis

[Monk]

any questions?

Yes - why do some people still insist that evolution is somehow less plausible than talking to invisible bearded man in the sky?

[The Doctor]

So when you said "some people" you really meant "one person"?

Some people, one person - does the plurality really matter?

Yes - why do some people still insist that evolution is somehow less plausible than talking to invisible bearded man in the sky?

Because they misunderstand evolution. Or they're borderline insane - I'm not sure which one.

[Vacamion]

I don't think the problem is the stuff which El Empty believes. You could spend all day on the stuff Mr Empty posts on here.

No, the problem is that some schools teach children that evolution is one of a number of competing explanations.

They are only competing to the same extent that a 747 and a magic carpet are competing modes of traversing the Atlantic.

[Carl the Llama]

Or to put it simply - as those shared ERV's exist, and are shared by 100% of both species, both species must have had a common ancestor.

tl;dr - speciation observed numerous times, ERV's are conclusive proof of common ancestry, which is further evidence for evolution.

any questions?

Why is that the only explanation?

Why can't it be the case that humans and chimps simply have many similarities in genetic make up as a necessity of each species' design?

[Zingari]

Whilst I might not have a problem accepting that humans evolved from some ape like creatures , I do have a big problem accepting that ultimately everything “blindly†evolved from a bubbling soup of gases and minerals .

How can humans ( and other life forms) with creative minds ,and emotions , feelings and all the other things that set us apart from mere chemical actions have just “evolved†blindly ? .

How can something that can think just come out of something that doesn’t without some form of creative influence? It’s like just accepting cars evolved without any thought just because observing different cars over the decades “proves†this

My own opinion is that we will never understand some things and do not even have the capacity

Anyone accepting “blind evolution†( with no creative influence) hasn’t fully understood the enormous problems with it .

[The Doctor]

Why is that the only explanation?

Why can't it be the case that humans and chimps simply have many similarities in genetic make up as a necessity of each species' design?

because those ERV's don't affect the genetic expression, they don't affect a species design - they are remnants of old diseases. They aren't just the like the similarities in DNA due to our physiological similarities (we share ~95% of our DNA with apes - we just have one less chromosome because our chromosome 2 is the fusion of two of theirs), rather they are just old bits of virus DNA that infected an ancestor and was retained in meiosis and so passed down to the next generation ad infinitum, and due to the size of the genome it's statistically impossible for them to occur in two species completely separately from each other. To share ERV's requires a common ancestor.

[Manwell Pablo]

because those ERV's don't affect the genetic expression, they don't affect a species design - they are remnants of old diseases. They aren't just the like the similarities in DNA due to our physiological similarities (we share ~95% of our DNA with apes - we just have one less chromosome because our chromosome 2 is the fusion of two of theirs), rather they are just old bits of virus DNA that infected an ancestor and was retained in meiosis and so passed down to the next generation ad infinitum, and due to the size of the genome it's statistically impossible for them to occur in two species completely separately from each other. To share ERV's requires a common ancestor.

[The Doctor]

Whilst I might not have a problem accepting that humans evolved from some ape like creatures , I do have a big problem accepting that ultimately everything “blindly†evolved from a bubbling soup of gases and minerals .

How can humans ( and other life forms) with creative minds ,and emotions , feelings and all the other things that set us apart from mere chemical actions have just “evolved†blindly ? .

How can something that can think just come out of something that doesn’t without some form of creative influence? It’s like just accepting cars evolved without any thought just because observing different cars over the decades “proves†this

My own opinion is that we will never understand some things and do not even have the capacity

Anyone accepting “blind evolution†( with no creative influence) hasn’t fully understood the enormous problems with it .

Now, coming from soups of gases and minerals you're talking about the origins of life - Evolution doesn't seek to explain that. Evolution explains variation, it doesn't even look at the origins of life.

Those emotions are just chemical reactions, and memories, thoughts etc. are just electrical impulses.

There's no creative influence - the influence on evolution is environmental pressure and so natural selection.

[MC Prussian]

I'm with Pearl Jam on this matter (and that's my only two cents about this topic):

[purpleronnie]

I'm with Pearl Jam on this matter (and that's my only two cents about this topic):

tune my friend.

[Zingari]

Now, coming from soups of gases and minerals you're talking about the origins of life - Evolution doesn't seek to explain that. Evolution explains variation, it doesn't even look at the origins of life.

Those emotions are just chemical reactions, and memories, thoughts etc. are just electrical impulses.

There's no creative influence - the influence on evolution is environmental pressure and so natural selection.

Thats just weasel words , Evolutionist have said that everything ultimately evolved from this ( even leaving aside the beginning or creation of actual life)

if you really believe that emotions are merely "chemical reactions" you need to explain what is controlling them .

[Carl the Llama]

because those ERV's don't affect the genetic expression, they don't affect a species design - they are remnants of old diseases. They aren't just the like the similarities in DNA due to our physiological similarities (we share ~95% of our DNA with apes - we just have one less chromosome because our chromosome 2 is the fusion of two of theirs), rather they are just old bits of virus DNA that infected an ancestor and was retained in meiosis and so passed down to the next generation ad infinitum, and due to the size of the genome it's statistically impossible for them to occur in two species completely separately from each other. To share ERV's requires a common ancestor.

Why is it impossible for the 2 different species to have the same virus at some point thousands of years ago and hence pass down the same ERVs, but from different origins?

[whoareyaaa]

What I can't understand is why are we not evolving today into some super human if that is the case of evolution, why did it have to stop at the human being we are today?

p.s this might not even be related to the topic but though I would throw it in there!

[The Doctor]

Thats just weasel words , Evolutionist have said that everything ultimately evolved from this ( even leaving aside the beginning or creation of actual life)

if you really believe that emotions are merely "chemical reactions" you need to explain what is controlling them .

People tend to say that yes, however it's not under the remit of the theory of evolution. Evolution is concerned with variation over time, not the origins. Just because several people who accept evolution also believe a form of abiogenesis was the origin of life on earth, doesn't mean it's covered by evolution any more than people who accept stellar death believing in string theory means string theory is a part the death of stars.

What exactly do you mean? Emotions are just chemical reactions, or more accurately the change in the concentration of various chemicals in the brain (e.g. seretonin) - they're excreted from various glands following stimulation.

Why is it impossible for the 2 different species to have the same virus at some point thousands of years ago and hence pass down the same ERVs, but from different origins?

Because ERV's make up less than 5% of the total genome. The sheer size of the genome, and the number of possible ERV's that could remain means that for the same ERV to insert into the same loci in two different genomes is so incredibly low that it's statistically impossible.