Darwin’s finches

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zimmer_beaks_finch_600.jpg

Darwin’s finches – science tattoos. Photograph courtesy of Carl Zimmer, The Loom.

104 Comments

Were they done by John Freshwater?

I read that the finches in question can interbreed- is this true?

I read that the finches in question can interbreed- is this true?

I’ve read that lions and tigers can interbreed, too. Was there some point to mentioning this for finches as well?

Henry J

2oldstroke said:

I read that the finches in question can interbreed- is this true?

Some have been observed to interbreed, albeit very rarely. They don’t interbreed to the extent that they maintain distinctive populations, which is all that really matters for divergence to occur.

My understanding of the theory is, “don’t interbreed” always precedes “can’t interbreed” by some sizeable number of generations.

That’s impressive! I don’t know anything about tattoos, but I think you’d really have to trust your tattoo artist to ask for such a technically challenging tattoo. It’s lucky they didn’t end up with Darwin’s Blotches.

Peter Grant says the rate of interbreeding between G. fortis and G. scandens occurs between less than 5% of the total # of breeding pairs (Grant, 1994, Evol. Ecol. 8:598-617).

Jonathan Wells, on the other hand, clamed there is enough hybridization to collapse the number of species(Icons of Evolution, 2000), but that claim is refuted when one actually looks at the details of the Grants’ work and not some conjecture made by Peter Grant when asked to speculate how long it might take to merge species through hybridization. And as most of us here know, Jonathan Wells is a filthy liar.

jswise said:

That’s impressive! I don’t know anything about tattoos, but I think you’d really have to trust your tattoo artist to ask for such a technically challenging tattoo. It’s lucky they didn’t end up with Darwin’s Blotches.

I just want to know what’s going to happen when they find the intermediate finch between #2 and #3.

I just want to know what’s going to happen when they find the intermediate finch between #2 and #3.

Wouldn’t that be the mainland finches that all of them are descended from?

Obviously, supposed to depict Lamarkian type evolution. Flex the muscles, or just gain weight and watch the evolution of the tatoo.

Henry J said:

I just want to know what’s going to happen when they find the intermediate finch between #2 and #3.

Wouldn’t that be the mainland finches that all of them are descended from?

But… that wouldn’t be nearly as funny.

But, but… THEY’RE STILL JUST TATTOOS!!!

What I want to see is a tattoo turning into something which is not a tattoo, like a piercing.

A tattoo is so complex. It can’t be drawn by just chance. You see, tattoos require tattooers!

And no, a book called “The blind tattooer” won’t do very well.

“And no, a book called “The blind tattooer” won’t do very well. “

No, but it would make a good Monty Python or Tim Conway sketch!

Is it a proven fact that changes in beak size are random? Or is it more the case that no evidence exists to prove the existence of a cause. Lion (IRC)

Finch beaks get bigger. Then finch beaks get smaller. Then ..er, they get bigger again. Seems like a clear edge of evolution. Has anyone seen finches break through this adaptive range?

Lion IRC said:

Is it a proven fact that changes in beak size are random? Or is it more the case that no evidence exists to prove the existence of a cause. Lion (IRC)

No, moron. Changes in beak size are in response to the size of available seeds. During wet seasons, plants produce large seeds and the finches that have large beaks have a competitive advantage over the small beaked finches. During droughts, plants produce small seeds, and the small-beaked finches are at an advantage, as they do not need to make the otherwise costly metabolic investment of growing large beaks.

They explain this in just about any competently written biology textbook.

Steve P. said:

Finch beaks get bigger. Then finch beaks get smaller. Then ..er, they get bigger again. Seems like a clear edge of evolution. Has anyone seen finches break through this adaptive range?

I would recommend actually reading the relevant literature, or even reading textbooks on elementary biology, evolution, or ecology, but, given your previous behavior, yuan to donuts says you would sooner pound 24 inch knitting needles up your nose with a mallet than make a half-assed attempt to read the appropriate literature.

What I want to see is a tattoo turning into something which is not a tattoo, like a piercing.

Sounds like something (somebody?) on Fantasy Island.

Henry J

antiplastic said:

But, but… THEY’RE STILL JUST TATTOOS!!!

What I want to see is a tattoo turning into something which is not a tattoo, like a piercing.

How about a Tattoo that turns into a NickNack?

Hi Stanton, Thanks for the explanation and the good natured, jovial ad hom. It’s good that we can kid around calling each other morons and know its only in jest. So just to clarify, do I understand you correctly that there are no mutations at the genetic level which result in bigger or smaller beaks in the offspring of a medium beak sized finch. I thought (perhaps mistakenly) that random mutations caused beak sizes to vary and natural selection accounted for certain beak sizes being less prevalent or non-existent. Best regards – Lion (IRC)

Lion IRC said:

Hi Stanton, Thanks for the explanation and the good natured, jovial ad hom. It’s good that we can kid around calling each other morons and know its only in jest.

I called you a “moron” because you were making moronic statements. If you want me to refrain from stating the obvious, perhaps it would be in our best interests if you made an effort to educate yourself in biology, first.

To be truthful, I am loath to give creationists the benefit of the doubt because the vast majority of creationists I’ve encountered either come with no intentions of good will in their hearts to begin with, or they never intend to discuss actual biology to begin with (such as the case of Steve P).

So just to clarify, do I understand you correctly that there are no mutations at the genetic level which result in bigger or smaller beaks in the offspring of a medium beak sized finch.

Beak size is governed by a suite of several genes, actually, and among the Galapagos finches, there is a spectrum of beak sizes, from large, to medium to small. Furthermore, blending of traits only occurs if there is incomplete dominance, which may not be the case with finches.

I thought (perhaps mistakenly) that random mutations caused beak sizes to vary and natural selection accounted for certain beak sizes being less prevalent or non-existent.

First off, please stop using the term “random mutation,” it makes you sound foolish, much in the way a person using the terms “wet water” or “skunky-smelling skunk” sounds foolish. Not everything in evolution revolves around mutations, random or otherwise.

Otherwise, yes, the persistence of particular traits in a population or a group of related populations does depend on environmental conditions and ecological opportunities, though some notable exceptions in certain populations do occur.

jovial ad hom.

I would normally say that it’s really an insult, but calling you a moron is a reasoned conclusion based on evidence, not an ad hominem.

Steve P. said:

Finch beaks get bigger. Then finch beaks get smaller. Then ..er, they get bigger again. Seems like a clear edge of evolution. Has anyone seen finches break through this adaptive range?

Actually, all of the finches in the Galapagos are demonstrably descended from birds on the South American mainland. So yes, the finches represent a spectacular example of speciation and adaptive radiation. Now Steve, why do you think that is? Is there any competition between finches? How do you explain the character displacement observed in sympatric populations if there is no competition? Are they all just one big happy family trying to help each other out? Come on Steve, explain the diversity of finch beaks to us. You know you want to.

Ichthyic said:

jovial ad hom.

I would normally say that it’s really an insult, but calling you a moron is a reasoned conclusion based on evidence, not an ad hominem.

Lion claimed in a previous post that evolutionists (allegedly) see no value in life because it evolved “randomly.” That is an ad hominem.

If “evolutionists” really did find no value in life, as creationists slanderously claim, why on earth would evolutionists bother to study life, let alone find enough interest get a tattoo the family tree of a taxon of finches? I find it painfully ironic that creationists, on the other hand, will claim this about evolutionists/atheists/scientists/pagans, yet, also dismiss the world as being the “devil’s kingdom,” and refuse to study it for fear of being ensnared by the devil.

DS said:

Steve P. said:

Finch beaks get bigger. Then finch beaks get smaller. Then ..er, they get bigger again. Seems like a clear edge of evolution. Has anyone seen finches break through this adaptive range?

Actually, all of the finches in the Galapagos are demonstrably descended from birds on the South American mainland. So yes, the finches represent a spectacular example of speciation and adaptive radiation. Now Steve, why do you think that is? Is there any competition between finches? How do you explain the character displacement observed in sympatric populations if there is no competition? Are they all just one big happy family trying to help each other out? Come on Steve, explain the diversity of finch beaks to us. You know you want to.

Yuan to donuts says that Steve has never heard of the “vampire finch,” and, as per the typical Intelligent Design proponent, doesn’t care to learn about it, either.

Lion IRC -

I have quite a number of questions for you, which I hope you will answer. I notice that you haven’t started out with insults this time, so, although I strongly defend the civility and content of Stanton’s contents, I will try to avoid them as well.

Is it a proven fact that changes in beak size are random?

I don’t understand your language here. The standard biological explanation would be that beak size is largely genetically determined, by more than one allele, much like human height. Much like human height, any genotype may be impacted by developmental/enviornmmental factors, but under normal circumstances, the phenotype would be largely genetically determined. Although there are multiple alleles in action, bigger-beaked finches would tend to have bigger-beaked offspring on average, just as having one or more tall human parent normally increases the likelihood of a tall human child. During a period when bigger-beaked finches have a relative competitive advantage, they tend to have more offspring, and we quickly see more bigger beaked finches in the population. However, the allelic combinations that lead to smaller beaks usually don’t go entirely extinct, by any means (they would be increasingly likely to as population size decreases or as big-beak-favoring conditions are prolonged, but depending on the exact allelic situation, might be very persistent for a long time, if there are many recessive alleles involved, for example). So when conditions switch and the small-beaked phenotype is favored, we see the exact same situation occur with regard to small beaks. New mutations may arise in genes that are related to beak size, but are not necessary in this scenario. Likewise, this is not an example of speciation (although such a situation could augment a trend to speciation in some circumstances), nor of extincition. It is primarily an example of natural selection.

Questions -

1. If you disagree with the standard scientific explanation, can you offer an alternative explanation? If, for example, a designer is at work, where does the designer act? Does the designer magically change the genotype of finch zygotes? Or does the designer act on the phenotype as a magical “environmental” influence, so that a finch may actually have genes for a small beak, but magically express a large beak? Or perhaps you have another alternate explanation that I haven’t anticipated.

2. Even if a designer is magically altering finches, why wouldn’t natural selection potentially happen anyway? Is there a rigorous way that we can differentiate between the designer’s acts and natural selection?

3. Do you understand the meanings of the terms “allele”, “recessive”, “dominant”, “genotype”, and “phenotype”? These terms are fairly easy to understand, and critical for an informed discussion, so please speak up if you are ignorant of them, or have read definitions that you could not understand.

Or is it more the case that no evidence exists to prove the existence of a cause. Lion (IRC)

If I understand this correctly, you are implying that maybe finch beak size has no known genetic controls.

Question - Are you literally denying genetics? As far as I know, even most creationists accept that genes code for proteins and heavily influence phenotype.

So just to clarify, do I understand you correctly that there are no mutations at the genetic level which result in bigger or smaller beaks in the offspring of a medium beak sized finch. I thought (perhaps mistakenly) that random mutations caused beak sizes to vary and natural selection accounted for certain beak sizes being less prevalent or non-existent. Best regards

All alleles presumably originated as “mutuations”, but we usually don’t use the term “mutation” that way. There are, as I explained above, alleles that impact on (usually determine, to a large degree), the size of beak which develops. Medium-beaked finches (note, of course, that there are two finch parents per offspring, a male and a female finch, not just one) can easily have large or small beaked offspring, just as medium sized humans can easily have tall or short offspring. Yet larger beaked finches are still more likely to have larger beaked offspring. As I explained above, significant new mutations may occur, but are not necessary to account for this scenario.

Assuming that you are merely mis-using the term “mutation” when you meant to say “existing alleles”, your understanding borders on being correct. Yet this contradicts your implications above that there are no genes related to beak size, and does not describe a scenario in which a designer must magically intervene.

Question - Which is it? Do you admit that some finches have bigger beaks than others, that this is to a large degree genetically determined, and that different beak sizes can be selected for under different environmental conditions? Or not?

Question - Why don’t you pay more attention to learning and using the appropriate, precise terminology (which is sometimes difficult even for us who bothered to educate ourselves)? The reason the terminology exists is to facilitate discussion and understanding.

I’d appreciate answers to my questions.

Stanton said: Yuan to donuts says that Steve has never heard of the “vampire finch,” and, as per the typical Intelligent Design proponent, doesn’t care to learn about it, either.

I hadn’t either, so I looked it up. Very cool. Call me strange, but I actually think the egg-eating behavior is more interesting than the blood-drinking.

Lion IRC -

Despite your stated interest in dialogue, my questions have gone unanswered. Perhaps you are working on the answers. In any case, for clarity, I will post them again. I won’t re-post all of the explanatory material that was in my original post to you, but please don’t fail to have a look at it.

Questions -

1. If you disagree with the standard scientific explanation, can you offer an alternative explanation? If, for example, a designer is at work, where does the designer act? Does the designer magically change the genotype of finch zygotes? Or does the designer act on the phenotype as a magical “environmental” influence, so that a finch may actually have genes for a small beak, but magically express a large beak? Or perhaps you have another alternate explanation that I haven’t anticipated.

2. Even if a designer is magically altering finches, why wouldn’t natural selection potentially happen anyway? Is there a rigorous way that we can differentiate between the designer’s acts and natural selection?

3. Do you understand the meanings of the terms “allele”, “recessive”, “dominant”, “genotype”, and “phenotype”? These terms are fairly easy to understand, and critical for an informed discussion, so please speak up if you are ignorant of them, or have read definitions that you could not understand.

Question - Are you literally denying genetics? As far as I know, even most creationists accept that genes code for proteins and heavily influence phenotype.

Question - Which is it? Do you admit that some finches have bigger beaks than others, that this is to a large degree genetically determined, and that different beak sizes can be selected for under different environmental conditions? Or not?

Question - Why don’t you pay more attention to learning and using the appropriate, precise terminology (which is sometimes difficult even for us who bothered to educate ourselves)? The reason the terminology exists is to facilitate discussion and understanding.

Lion IRC -

Good news.

You may not have had a chance to respond to my questions today. Possibly your busy.

It may even happen that you will appear on another thread before getting around to answering them. It’s easy to get distracted.

For your convenience, I have saved a copy of my posts here, so that if and when you do return, we will be able to take up the discussion again.

Oops, unforgivable. That’s what I get for not previewing a “simple” post.

“Your” instead of “you’re”.

I doubt that lion will ever ‘get’it, but all these explanations sure helped me. thanks ya’ll.

What she said.

So to summarize:

Mutations Are NOT random in the sense that:

1) Not all types of mutations are equally likely

2) Not all nucleotides are equally likely to mutate

3) Not all mutations are equally likely to be repaired

4) Not all mutations are equally likely to be passed on to offspring

5) Not all mutations are equally likely to increase in frequency in the population in every environment

Mutations ARE random in the sense that the distribution of mutations:

1) Is not statistically different from that expected by random chance

2) Is not affected by the current needs of the organism

3) Is not affected by the future needs of the organism

4) Is not ordinarily affected by the desires of human beings

5) Is not altered by any supernatural intervention (at least as far as we can tell)

Hi DS,

You forgot one thing in your summary.

Apparently since 1900 we have given up seeking a unified theory of everything - except for the theory that “There NEVER will be a TOE.”

(chaos / uncertainty / unpredictability - quantum weirdness trumps science)

Which sort of emphasizes my point.

What Heisenberg called “uncertainty” should have more accurately been paraphrased as follows;

“We don’t yet know exactly what’s going on here because the instruments we are using are not small enough and precise enough to see what is actually going on.”

“Random” means all possible causes empirically verified and ruled out.

“Apparently random” means we think we have eliminated all the causes we can think of so far or there are so many contributing variables that we just can’t be bothered finding out which one matters most.

But please don’t dress up a concept like random mutation with “Kings New Clothes” jargon. Just call a spade a spade.

You either know why something happens or you dont.

Lion (IRC)

Lion, you are making an idiot out of yourself again.

We have repeatedly pointed out to you that you are misusing the term “random” in your pathetic attempt to disparage mutation’s role in evolution.

Please go away: you are a stupid and annoying hypocrite.

I mean, honestly, Lion, if you claim that “random mutations” aren’t what help drive evolution, then what is, and why haven’t you put forth any evidence to support your claim?

Or, is this all a part of your inane master plan of trying to paint science and scientists as being evil and incompetent so you can wow us when you whip out God with His Magic Pixie Wand as THE ANSWER tm?

I mean, Lion, you have to be aware that there is an earthshakingly valid reason why we view you as being a malicious idiot.

Lion opined:

“Random” means all possible causes empirically verified and ruled out.

“When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean – neither more nor less.”

Lion you are wrong:

“In quantum mechanics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. This statement has been interpreted in two different ways. According to Heisenberg its meaning is that it is impossible to determine simultaneously both the position and velocity of an electron or any other particle with any great degree of accuracy or certainty. According to others (for instance Ballentine)[1] this is not a statement about the limitations of a researcher’s ability to measure particular quantities of a system, but it is a statement about the nature of the system itself as described by the equations of quantum mechanics.

In quantum physics, a particle is described by a wave packet, which gives rise to this phenomenon. Consider the measurement of the absolute position of a particle. It could be anywhere the particle’s wave packet has non-zero amplitude, meaning the position is uncertain - it could be almost anywhere along the wave packet. To obtain an accurate reading of position, this wave packet must be ‘compressed’ as much as possible, meaning it must be made up of increasing numbers of sine waves added together. The momentum of the particle is proportional to the wavelength of one of these waves, but it could be any of them. So a more accurate position measurement–by adding together more waves–means the momentum measurement becomes less accurate (and vice versa).”

Wiki’s good for some things.

Note that this has nothing to do with the size and precision of instruments. It is the nature of… well, Nature, actually.

See, Lion? Even you can learn something!

fnxtr said:

See, Lion? Even you can learn something!

No he can’t: we’re dealing with an idiot who has not only ignored all of our attempts to correct his incorrect use of “random” and “random mutation,” but has also trotted out Haldaine and the unifying theory to justify his idiocy, as well as claimed that Richard Dawkin’s use of “random” and “random mutation” somehow justifies his own misuse and abuse of those words.

Lyin,

You have been told. We understand exactly what the mechanisms of mutations are at the molecular level. If you are ignorant of this evidence then you have no right to any opinion. Now if you want to claim that mutations are not random you must choose a meaning of the word, then demonstrate how mutations are not random in that sense. Until you do this you are just playing word games and ignoring all evidence. No one cares what you think. Either grow up and have an intelligent adult conversation or go away.

Evolutionary Biologists Rethink Evolution

by Brian Thomas, M.S. *

But the accumulation and selection of mutations does not explain certain things that biologists have observed. For example, University of Arizona biologist Alexander Badaev, who has tracked over 12,000 house finches near Missoula, Montana, for over a decade, has noticed rapid changes in their beak shapes. A recent article in The Scientist pointed out that “the only way for finches to survive would be if their beak shape had changed rapidly—too rapidly to have resulted from just random mutations.”2 Badaev’s formal results will be published in an upcoming issue of the Philosophical Transactions of the Royal Society.

These finch finds parallel the rapid changes in beak shapes seen in Darwin’s finches on the Galapagos Islands.3 Much evidence, in fact, has been accumulating regarding biological changes that occur too fast for the slow and gradual amassing of mutations, as per the modern synthesis, to explain.4

References

2. Grant, B. 2010. Some biologists are calling for a rethink of the rules of evolution. The Scientist. 24 (1): 25-30. 3. Thomas, B. New Finch Species Shows Conservation, Not Macroevolution. ICR News. Posted on icr.org December 9, 2009, accessed January 25, 2010. 4. Reproducing Early and Often is the Key to Rapid Evolution in Plants. Yale University press release, October 2, 2008, reporting on research published in Smith, S. A. and M. J. Donoghue. 2008. Rates of Molecular Evolution Are Linked to Life History in Flowering Plants. Science. 322 (5898): 86-89. * Mr. Thomas is Science Writer at the Institute for Creation Research.

Article posted on February 3, 2010.

You know Henry, you don’t even quotemine well. A complaint about random mutation,even taken out of context, hardly provides support for creationism. There are many other evolutionary mechanisms for change.

But just to make the beat down comprehensive, here’s the next paragraph:

How was this possible? To answer the question, Badyaev looked into the developmental patterns that give rise to the beak’s structure in house finches. He found a complex interplay of processes, such as the migration of five islands of neural crest cells that constitute skeletal beak components in the embryo. Interacting embryonic processes result in an initial level of phenotypic variation greater than what would be predicted from underlying genotypic variation alone.2

The author is clearly arguing that development plays a large(r) role in beak size. The Evo-Devo debate is interesting, but its mainstream science. The idea that this support creationism is laughable.

henry, we already know you are a dishonest idiot.

Please take a long walk off a short pier.

eric said:

You know Henry, you don’t even quotemine well. A complaint about random mutation,even taken out of context, hardly provides support for creationism. There are many other evolutionary mechanisms for change.

But just to make the beat down comprehensive, here’s the next paragraph:

How was this possible? To answer the question, Badyaev looked into the developmental patterns that give rise to the beak’s structure in house finches. He found a complex interplay of processes, such as the migration of five islands of neural crest cells that constitute skeletal beak components in the embryo. Interacting embryonic processes result in an initial level of phenotypic variation greater than what would be predicted from underlying genotypic variation alone.2

The author is clearly arguing that development plays a large(r) role in beak size. The Evo-Devo debate is interesting, but its mainstream science. The idea that this support creationism is laughable.

It looks like the ability for variation in beak sizes was built in. There isn’t any room for the modern synthesis theory since the changes couldn’t have been random mutations.

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This page contains a single entry by Matt Young published on January 18, 2010 12:00 PM.

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