Facts for evolution

lucaspa · #1 17th October 2003, 02:15 PM

In another thread was posted:

Originally Posted by Vintersorg

And no one has proven evolution, if you think they have, then post the facts on this forum so i can read them.

Well everyone, here is the thread for that. Evos, bring on the facts. Bushido and TrueCreation, just copy everything here and use it for your essays on your proposed websites.

I'll start off with just a few references everyone can get either on the web or in the journals at their public library.

Evolution of complex organs
David N. Reznick, Mariana Mateos, and Mark S. Springer Independent Origins and Rapid Evolution of the Placenta in the Fish Genus Poeciliopsis Science 298: 1018-1020, Nov. 1, 2002. Intermediate steps in same genus. http://www.sciencemag.org/cgi/conten.../298/5595/1018 News article at: http://www.sciencemag.org/cgi/conten.../298/5595/945a
2. RO Prum and AH Brush, Which came first, the feather or the bird? Scientific American, 84-93, March 2003.
3. Zou H, Niswander L , Requirement for BMP signaling in interdigital apoptosisand scale formation. Science 1996 May 3;272(5262):738-41 "Expressionof dnBMPR in chicken embryonic hind limbs greatly reduced interdigital apoptosis and resulted in webbed feet. In addition, scales were transformed into feathers."
4. http://abcnews.go.com/sections/scien...pus990310.html Turning octopus suckers into light bulbs

Raterus · #2 17th October 2003, 02:49 PM

First two links cannot be accessed

Third link was intersting, but where is their proof in the DNA record? Do you have more information on this? Anyone can write an article, and ABC will believe anything

--Michael

wblastyn · #3 17th October 2003, 02:55 PM

Originally Posted by Raterus

First two links cannot be accessed

Third link was intersting, but where is their proof in the DNA record? Do you have more information on this? Anyone can write an article, and ABC will believe anything

--Michael

Well if you don't trust scientists why don't you go get a degree and look at the evidence yourself.

lucaspa · #4 17th October 2003, 03:53 PM

Originally Posted by Raterus

First two links cannot be accessed

You don't have a subscription to Science.

You'll just have to do the old-fashioned bit about going to the library.

Same with the last record:
Light-emitting suckers in an ctopusSönke Johnsen, Elisabeth J. Balser, Edith A. Widder
Nature

398, 113 - 114 (11 Mar 1999) That's the peer-reviewed article.

Third link was intersting, but where is their proof in the DNA record?

Why do you think you need a DNA record for "proof"?

"The existence of bioluminescence in the suckers of finned octopods has been considered before but never verified. The blind, finned octopod Cirrothauma murrayi has small bodies that have been suggested to be light organs4 or nerve ganglia5, but no luminescence has been observed.
When stimulated, the suckers of S. syrtensis (Fig. 1a) emit moderately bright, blue-green light with a maximum wavelength of 470 nm (Fig. 1b), which can last for up to 5 min. Individual light organs either glow dimly and continuously, or blink on and off brightly every 1-2 s. These organs could be capable of luminescence, and no other part of the body emitted light. The suckers were unable to attach to surfaces, indicating that, unlike typical octopod suckers, they have no adhesive function.
The light organs of S. syrtensis are arranged in a single row along the length of the oral surface of each arm. The overall appearance of the light organs is similar to that of octopod suckers6. They are button-like structures raised above the surface of the arm but are not supported on stalks or peduncles.

Like suckers, the organs consist of an outer collar of columnar epidermal cells surrounding a cup-like depressed region called the infundibulum (Fig. 2a). At the centre of the infundibulum, a pore opens into the acetabulum, which, in S. syrtensis, is a narrow channel situated within the organ. The cells of the epidermal collar, infundibulum and acetabulum are covered by a cuticle (Fig. 2a,c). At the outer rim of the infundibulum, the cuticle is elaborated to form a circle of hook-shaped denticles (Fig. 2b). Each light organ is supported by a sub-acetabular ganglion (Fig. 2c) that connects with the main brachial nerve cord.
The overall morphology is typical of octopod suckers6, but ultrastructural examination shows that the radial, circular and longitudinal muscles of the infundibulum and acetabulum, which are typically well-developed in suckers, are greatly reduced. The muscles are replaced by light-producing cells, or photocytes, limiting the mechanical function of the organ.

Although bioluminescence is ubiquitous in the ocean, study of its evolution has been hindered by the absence of a fossil record7. Light organs that retain structural traits indicative of a previous function therefore offer a rare view of their evolutionary history. The duality of sucker and photophore traits in this finned octopod supports the idea that the light organs are modified suckers. This transition of function may have occurred during colonization of the pelagic deep sea from the shallow-water benthos."

lucaspa · #5 17th October 2003, 03:55 PM

Now, if you want DNA linkage:
1a. http://www.nature.com/cgi-taf/DynaPa...ure716_fs.html Hox protein mutation and macroevolution of the insect body plan. Ronshaugen M, McGinnis N, McGinnis W. Nature 2002 Feb 21;415(6874):914-7 Mutate one serine to alanine and change limb # from multiple limbs of crustaceans to 6 limbs of insects. "To test this, we generated mutant versions of Artemia Ubx in which C-terminal Ser/Thr residues were mutated to Ala. In the first such mutant (Art Ubx S/T to A 1–5), the first five Ser and Thr residues in the C-terminus are changed to Ala. This mutant Ubx has little limb-repression function, similar to wild-type Artemia Ubx (Fig. 3). However, the mutation of one additional Ser in a CKII consensus site (Art Ubx S/T to A 1–5 and 7) results in a Ubx that strongly represses embryonic limbs (Fig. 3)."

joelazcr · #6 17th October 2003, 05:57 PM

Independent Origins and Rapid Evolution of the Placenta in the Fish Genus Poeciliopsis

Here are what appears to be the facts:

"Fish in the genus Poeciliopsis (Poeciliidae) display variation in live-bearing that ranges from species that retain eggs after fertilization with no further maternal provisioning (lecithotrophy or yolk feeding) to those that have variable amounts of maternal provisioning after fertilization (matrotrophy or mother feeding. Turner found that high levels of postfertilization provisioning are associated with an elaboration of maternal and fetal tissues that he named the "follicular pseudoplacenta" in recognition of their apparent functional similarity to a mammalian placenta. Furthermore, he found a positive association between the amount of maternal provisioning provided before versus after fertilization and the elaboration of structures that form the interface between mothers and developing young. There thus appears to be variation from species that have no such specialized tissues to those with highly elaborate placentas, plus a range of species in between with less elaborate placentas.

We quantify maternal provisioning with the "matrotrophy index" (MI), which is the estimated dry mass of offspring at birth divided by the dry mass of the egg at fertilization."

Here's the interpretation of these facts:

It is assumed that the range of maternal and fetal tissues are in various stages of evolution.

They use further evolutionary assumptions to build phylogenetic trees
and estimate evolutionary timelines using molecular clocks and dated volcanic eruptions. They conclude that complex adaptations can evolve rapidly.

Here are some interesting quotes from the article:

"It’s one of the oldest riddles in evolutionary biology: How does natural selection gradually create an eye, or any complex organ for that matter? The puzzle troubled Charles Darwin, who nevertheless gamely nailed together a ladder of how it might have happened-from photoreceptor cells to highly refined orbits-by drawing examples from living organisms such as mollusks and arthropods. But holes in this progression have persistently bothered evolutionary biologists and left openings that creationists have been only too happy to exploit. Now a team of researchers presents a model system for studying the evolution of complex organs-in this case, the placenta-that Darwin could only dream about.

Placentas serve as a decent stand-in for eyes and other complex organs such as the heart or kidney whose histories evolutionary biologists have never been able to trace, Reznick and colleagues argue. By definition, complex organs are composites of independently derived features; for instance, the human eye focuses light and also perceives color. In the case of the placenta, the organ provides nutrients for the fetus while simultaneously managing waste products and regulating gas exchanges. Evidence of the intermediate steps for acquiring such organs is missing from the fossil record, enabling creationists to claim they were "created" de novo.

Another Yale biologist cautions that Reznick has not proved that this little guppy placenta is a complex organ, and Reznick admits it. But at least these guppies might provide a glimpse of how it happened. "We can’t ask how this kind of adaptation evolved with mammals because it only happened once over 100 million years ago," he says. Morell agrees: "But like the evolution of the eye, the evolution of the mammalian placenta is lost in history."

The article ends with a directive for more genetic research.

"Experimentally accessible phenomena in Poeciliidae might include the progressive development of the genetic and morphological mechanisms associated with maternal provisioning or the escalating intergenomic conflict associated first with egg retention and then with the increasing commitment of maternal resources after fertilization."

If this genetic research is ever done, how will it be interpreted if
each Poeciliidae species contain the genes for the advanced
follicular pseudoplacenta, just not fully expressed?

ThePhoenix · #7 17th October 2003, 06:08 PM

First two links worked for me. Maybe the college has a subscription? Anyway, the articles were really interesting.

Cantuar · #8 17th October 2003, 07:24 PM

For the Reznick paper, just google on keywords in the title and you'll come across a pdf version of the paper. Or get a subscription to Science; it isn't that expensive.

Torsoboy · #9 18th October 2003, 03:56 PM

Maybe, but I think the landing should have been done on the south of France. The Nazi's hadn't properly reinforced the south, and an attack from North Africa could have saved lives, for both the Allies and Axis.

lucaspa · #10 18th October 2003, 07:05 PM

Joel, you accessed the descriptive news article, but not the main paper.

Originally Posted by joelazcr

Here's the interpretation of these facts:

It is assumed that the range of maternal and fetal tissues are in various stages of evolution.

That's not an assumption. It's a conclusion. Remember the deductions from the theories of creationism and evolution. If creationism is correct, then there should be no intermediate stages in the formation of placentas: they are complex and had to have been made directly and in complete form. So, first the evidence falsifies creationism.

Second, evolution states that if it is true then there should be intermediate stages from egg formation to placentas. This is what is found in the fish. A series of intermediates in the formation of placentas among species that are otherwise very similar. As you said: the fact is "variation from species that have no such specialized tissues to those with highly elaborate placentas, plus a range of species in between with less elaborate placentas."

Therefore, the conclusion is that the intermediate placentas represent an evolutionary sequence.

They use further evolutionary assumptions to build phylogenetic trees

and estimate evolutionary timelines using molecular clocks and dated volcanic eruptions. They conclude that complex adaptations can evolve rapidly.

Now, once they concluded that there was evolution, then it is time to do additional hypotheses. In this case those are the lineage relationships and estimates of the time of the sequence by independent dating methods.

Here are some interesting quotes from the article:

"It’s one of the oldest riddles in evolutionary biology: How does natural selection gradually create an eye, or any complex organ for that matter? ... Now a team of researchers presents a model system for studying the evolution of complex organs-in this case, the placenta-that Darwin could only dream about.

Notice that we are dealing here with natural selection. Which should leave intermediates. Direct creation or manufacture, the common denominator of all versions of creationism, should not have intermediates.

"Another Yale biologist cautions that Reznick has not proved that this little guppy placenta is a complex organ, and Reznick admits it. But at least these guppies might provide a glimpse of how it happened. "We can’t ask how this kind of adaptation evolved with mammals because it only happened once over 100 million years ago," he says. Morell agrees: "But like the evolution of the eye, the evolution of the mammalian placenta is lost in history."

You misquoted! Did you think I wouldn't check! Shame on you to violate the 9th Commandment like that! Joel, this isn't the first time you've misquoted. Why do you want to destroy your credibility that way?

The real quote:
"Other researchers, such as Günter Wagner, an evolutionary biologist who is also at Yale, caution that Reznick has yet to demonstrate convincingly that the poeciliids' placenta is a complex organ. But even with this caveat, Wagner concedes that the poeciliid model offers evolutionary biologists a rare opportunity: "We should welcome any model, and especially one like this that has several related species with all the variations in the evolution of this trait."
"Reznick admits that the poeciliid placenta might not be as sophisticated as the mammalian placenta. But like the evolution of the eye, the evolution of the mammalian placenta is lost in history. "We can't ask how this kind of adaptation evolved with mammals because it only happened once over 100 million years ago," he says. The answer might come instead from small, guppylike fish. "

Very different.

The article ends with a directive for more genetic research.

"Experimentally accessible phenomena in Poeciliidae might include the progressive development of the genetic and morphological mechanisms associated with maternal provisioning or the escalating intergenomic conflict associated first with egg retention and then with the increasing commitment of maternal resources after fertilization."

It's not a directive. It's stating that the different species provide the opportunity for genetic research to compare genes.

If this genetic research is ever done, how will it be interpreted if

each Poeciliidae species contain the genes for the advanced follicular pseudoplacenta, just not fully expressed?

There are two "ifs" there. The first -- that the genes will be compared -- is almost certain to take place sometime. I suspect Reznick and company have already submitted the grant for funds to do so.

The second "if" is not at all certain. What I predict to happen is that the genes will be there, but won't code for advanced follicular development. Instead, they will be different DNA sequences between species and the correlation of sequence to function will then be determined.

What you are proposing is that all the genes are there, but that in the less advanced placental species, some genes are not being expressed. IOW, "advanced" placentas required more genes than less advanced ones, and that the extra genes are in the species with less advanced plancentas, but are "dormant".

Why would those extra genes even be there under creationism? If the species are directly made by a Creator, why install extra genes that would only be needed if the species "evolved" later?

If you are thinking the genes were put there so that the fish could "adapt" and gain advanced placentas later, then random mutations would inactivate them or distort them so badly they won't function.

This has already been shown with an alternative developmental pathway in Drosophila. The pathway is suppressed by the protein HSP90 (heat shock protein 90). When the flies are under heat stress, the HSP90 is used to combat the stress and is pulled from suppressing the developmental pathways. The resulting flies are very deformed from the mutations that accumulated in the pathways that were never removed by natural selection.

2. E Pennisi, Heat shock protein mutes genetic changes. Science282: 1796, Dec. 4, 1998. Describes Nature article on acceleratedevolution. HSP 90 suppresses some developmental pathways, allowing themto accumulate mutations. When HSP 90 is tied up protecting from heat stress,then these pathways become active, giving large morphological changes since thesmall mutations are in HOX genes.
3. SL Rutherford and S Lindquist, HSP90 as a capacitor for morphological evolution. Nature 396: 336-342, Nov.26, 1998. Primary paper for above. Look at pictures of large changes in the flies.

This data falsifies your hypothesis.