Tag Archives: Gene

Convergence detected in the genetic structure of bats and dolphins

Apologetics and the progress of science
Apologetics and the progress of science

We have to start this post with the definition of convergence in biology.

In evolutionary biology, convergent evolution is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

It is the opposite of divergent evolution, where related species evolve different traits.

On a molecular level, this can happen due to random mutation unrelated to adaptive changes; see long branch attraction. In cultural evolution, convergent evolution is the development of similar cultural adaptations to similar environmental conditions by different peoples with different ancestral cultures. An example of convergent evolution is the similar nature of the flight/wings of insects, birds, pterosaurs, and bats.

All four serve the same function and are similar in structure, but each evolved independently.

Jonathan Wells explains the problem that convergence poses for naturalistic evolution:

Human designers reuse designs that work well. Life forms also reuse certain structures (the camera eye, for example, appears in humans and octopuses). How well does this evidence support Darwinian evolution? Does it support intelligent design more strongly?

Evolutionary biologists attribute similar biological structures to either common descent or convergence. Structures are said to result from convergence if they evolved independently from distinct lines of organisms. Darwinian explanations of convergence strain credulity because they must account for how trial-and-error tinkering (natural selection acting on random variations) could produce strikingly similar structures in widely different organisms and environments. It’s one thing for evolution to explain similarity by common descent—the same structure is then just carried along in different lineages. It’s another to explain it as the result of blind tinkering that happened to hit on the same structure multiple times. Design proponents attribute such similar structures to common design (just as an engineer may use the same parts in different machines). If human designers frequently reuse successful designs, the designer of nature can surely do the same.

I’m a software engineer, and we re-use components all the time for different programs that have no “common ancestor”. E.g. – I can develop my String function library and use it in my web application and my Eclipse IDE plug-in, and those two Java programs have nothing in common. So you find the same bits in two different programs because I am the developer of both programs. But the two programs don’t extend from a common program that was used for some other purpose – they have no “common ancestor” program.

Now with that in mind, take a look at this recent article from Science Daily, which Mysterious Micah sent me.

Excerpt:

The evolution of similar traits in different species, a process known as convergent evolution, is widespread not only at the physical level, but also at the genetic level, according to new research led by scientists at Queen Mary University of London and published in Nature this week.

The scientists investigated the genomic basis for echolocation, one of the most well-known examples of convergent evolution to examine the frequency of the process at a genomic level.

Echolocation is a complex physical trait that involves the production, reception and auditory processing of ultrasonic pulses for detecting unseen obstacles or tracking down prey, and has evolved separately in different groups of bats and cetaceans (including dolphins).

The scientists carried out one of the largest genome-wide surveys of its type to discover the extent to which convergent evolution of a physical feature involves the same genes.

They compared genomic sequences of 22 mammals, including the genomes of bats and dolphins, which independently evolved echolocation, and found genetic signatures consistent with convergence in nearly 200 different genomic regions concentrated in several ‘hearing genes’.

[…]Consistent with an involvement in echolocation, signs of convergence among bats and the bottlenose dolphin were seen in many genes previously implicated in hearing or deafness.

“We had expected to find identical changes in maybe a dozen or so genes but to see nearly 200 is incredible,” explains Dr Joe Parker, from Queen Mary’s School of Biological and Chemical Sciences and first author on the paper.

“We know natural selection is a potent driver of gene sequence evolution, but identifying so many examples where it produces nearly identical results in the genetic sequences of totally unrelated animals is astonishing.”

Nature is the most prestigious peer-reviewed science journal. This is solid material.

There is an earlier article from 2010 in New Scientist that talked about one of the previous genes that matched for hearing capability.

Excerpt:

Bats and dolphins trod an identical genetic path to evolve a vital component of the complex sonar systems they use to pursue and catch prey.

The finding is unusual, because although many creatures have independently evolved characteristics such as eyes, tusks or wings, they usually took diverse genetic routes to get there.

Analysis of a specific gene has now demonstrated that although bats live in air and dolphins in water, where sound travels five times faster, they independently evolved a near-identical gene that allows them to accept high-frequency sound in the ear – vital for sonar.

The gene makes prestin, a protein in hair cells of the cochlea, which is the organ in the inner ear where sonar signals are accepted and amplified. Prestin changes shape when exposed to high-frequency sound, and this in turn deforms the fine hair cells, setting off an electrical impulse to the brain. So the protein has the important jobs of detecting and selecting high-frequency sounds for amplification.

When researchers examined the molecular structure of the prestin gene from a range of animals, they found that the variants in echolocating bats and dolphins were virtually indistinguishable.

Indistinguishable genes in animals that don’t share a common ancestor? Maybe a better explanation for the evidence we have is – common designer.

Stephen C. Meyer lectures on intelligent design and the origin of life

A MUST-SEE lecture based on Dr. Stephen C. Meyer’s book “Signature in the Cell“.

You can get an MP3 of the lecture here. (30 MB)

I highly recommend watching the lecture, and looking at the slides. The quality of the video and the content is first class. There is some Q&A (9 minutes) at the end of the lecture.

Topics:

  • intelligent design is concerned with measuring the information-creating capabilities of natural forces like mutation and selection
  • Darwinists think that random mutations and natural selection can explain the origin and diversification of living systems
  • Darwinian mechanisms are capable of explaining small-scale adaptive changes within types of organisms
  • but there is skepticism, even among naturalists, that Darwinian mechanisms can explain the origin of animal designs
  • even if you concede that Darwinism can account for all of the basic animal body plans, there is still the problem of life’s origin
  • can Darwinian mechanisms explain the origin of the first life? Is there a good naturalistic hypothesis to explain it?
  • there are at least two places in the history of life where new information is needed: origin of life, and Cambrian explosion
  • overview of the structure of DNA and protein synthesis (he has helpful pictures and he uses the snap lock blocks, too)
  • the DNA molecule is composed of a sequence of bases that code for proteins, and the sequence is carefully selected to have biological function
  • meaningful sequences of things like computer code, English sentences, etc. require an adequate cause
  • it is very hard to arrive at a meaningful sequence of a non-trivial length by randomly picking symbols/letters
  • although any random sequence of letters is improbable, the vast majority of sequences are gibberish/non-compiling code
  • similarly, most random sequences of amino acids are lab-proven (Doug Axe’s work) to be non-functional gibberish
  • the research showing this was conducted at Cambridge University and published in the Journal of Molecular Biology
  • so, random mutation cannot explain the origin of the first living cell
  • however, even natural selection coupled with random mutation cannot explain the first living cell
  • there must already be replication in order for mutation and selection to work, so they can’t explain the first replicator
  • but the origin of life is the origin of the first replicator – there is no replication prior to the first replicator
  • the information in the first replicator cannot be explained by law, such as by chemical bonding affinities
  • the amino acids are attached like magnetic letters on a refrigerator
  • the magnetic force sticks the letters ON the fridge, but they don’t determine the specific sequence of the letters
  • if laws did determine the sequence of letters, then the sequences would be repetitive
  • the three materialist explanations – chance alone, chance and law, law alone – are not adequate to explain the effect
  • the best explanation is that an intelligent cause is responsible for the biological explanation in the first replicator
  • we know that intelligent causes can produce functional sequences of information, e.g. – English, Java code
  • the structure and design of DNA matches up nicely with the design patterns used by software engineers (like WK!)

There are some very good tips in this lecture so that you will be able to explain intelligent design to others in simple ways, using everyday household items and children’s toys to symbolize the amino acids, proteins, sugar phosphate backbones, etc.

Proteins are constructed from a sequence of amino acids:

A sequence of amino acids forming a protein
A sequence of amino acids forming a protein

Proteins sticking onto the double helix structure of DNA:

Some proteins sticking onto the sugar phosphate backbone
Some proteins sticking onto the sugar phosphate backbone

I highly, highly recommend this lecture. You will be delighted and you will learn something.

Here is an article that gives a general overview of how intelligent design challenges. If you want to read something more detailed about the material that he is covering in the lecture above related to the origin of life, there is a pretty good article here.

There is a good breakdown of some of the slides with helpful flow charts here on Uncommon Descent.

Positive arguments for Christian theism

Stephen C. Meyer lectures on intelligent design and the origin of life

A MUST-SEE lecture based on Dr. Stephen C. Meyer’s book “Signature in the Cell“.

You can get an MP3 of the lecture here. (30 MB)

I highly recommend watching the lecture, and looking at the slides. The quality of the video and the content is first class. There is some Q&A (9 minutes) at the end of the lecture.

Topics:

  • intelligent design is concerned with measuring the information-creating capabilities of natural forces like mutation and selection
  • Darwinists think that random mutations and natural selection can explain the origin and diversification of living systems
  • Darwinian mechanisms are capable of explaining small-scale adaptive changes within types of organisms
  • but there is skepticism, even among naturalists, that Darwinian mechanisms can explain the origin of animal designs
  • even if you concede that Darwinism can account for all of the basic animal body plans, there is still the problem of life’s origin
  • can Darwinian mechanisms explain the origin of the first life? Is there a good naturalistic hypothesis to explain it?
  • there are at least two places in the history of life where new information is needed: origin of life, and Cambrian explosion
  • overview of the structure of DNA and protein synthesis (he has helpful pictures and he uses the snap lock blocks, too)
  • the DNA molecule is composed of a sequence of proteins, and the sequence is carefully selected to have biological function
  • meaningful sequences of things like computer code, English sentences, etc. require an adequate cause
  • it is very hard to arrive at a meaningful sequence of a non-trivial length by randomly picking symbols/letters
  • although any random sequence of letters is improbable, the vast majority of sequences are gibberish/non-compiling code
  • similarly, most random sequences of amino acids are lab-proven (Doug Axe’s work) to be non-functional gibberish
  • the research showing this was conducted at Cambridge University and published in the Journal of Molecular Biology
  • so, random mutation cannot explain the origin of the first living cell
  • however, even natural selection coupled with random mutation cannot explain the first living cell
  • there must already be replication in order for mutation and selection to work, so they can’t explain the first replicator
  • but the origin of life is the origin of the first replicator – there is no replication prior to the first replicator
  • the information in the first replicator cannot be explained by law, such as by chemical bonding affinities
  • the amino acids are attached like magnetic letters on a refrigerator
  • the magnetic force sticks the letters ON the fridge, but they don’t determine the specific sequence of the letters
  • if laws did determine the sequence of letters, then the sequences would be repetitive
  • the three materialist explanations – chance alone, chance and law, law alone – are not adequate to explain the effect
  • the best explanation is that an intelligent cause is responsible for the biological explanation in the first replicator
  • we know that intelligent causes can produce functional sequences of information, e.g. – English, Java code
  • the structure and design of DNA matches up nicely with the design patterns used by software engineers (like WK!)

There are some very good tips in this lecture so that you will be able to explain intelligent design to others in simple ways, using everyday household items and children’s toys to symbolize the amino acids, proteins, sugar phosphate backbones, etc.

Proteins are constructed from a sequence of amino acids:

A sequence of amino acids forming a protein
A sequence of amino acids forming a protein

Proteins sticking onto the double helix structure of DNA:

Some proteins sticking onto the sugar phosphate backbone
Some proteins sticking onto the sugar phosphate backbone

I highly, highly recommend this lecture. You will be delighted and you will learn something.

Here is an article that gives a general overview of how intelligent design challenges. If you want to read something more detailed about the material that he is covering in the lecture above related to the origin of life, there is a pretty good article here.

UPDATE: There is a good breakdown of some of the slides with helpful flow charts here on Uncommon Descent.

Positive arguments for Christian theism

New study: bird origins poses a convergence challenge to common ancestry

Male normal gray cockatiel preens his wife's crest
Male cockatiel preens his wife’s crest

We have to start this post with the definition of convergence in biology.

In evolutionary biology, convergent evolution is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

It is the opposite of divergent evolution, where related species evolve different traits.

On a molecular level, this can happen due to random mutation unrelated to adaptive changes; see long branch attraction. In cultural evolution, convergent evolution is the development of similar cultural adaptations to similar environmental conditions by different peoples with different ancestral cultures. An example of convergent evolution is the similar nature of the flight/wings of insects, birds, pterosaurs, and bats.

All four serve the same function and are similar in structure, but each evolved independently.

And now, this new article on convergence in birds and humans, from Evolution News.

They write:

Everyone is familiar with the striking ability of certain birds (such as parrots) to vocalize speech, much as humans do. Well, according to the new papers published in Science that I wrote about earlier, confirming that birds arose explosively, those vocalization abilities are the result of “convergent evolution” at both the morphological and genetic levels.

Nature News reports, “The authors also conclude that vocal learning may have evolved independently in the ancestors of parrots, hummingbirds and songbirds.” But this is about more than just birds. According to a Science Daily article about the technical papers, the genetic “convergent evolution” extends to birds and humans:

“We’ve known for many years that the singing behavior of birds is similar to speech in humans — not identical, but similar — and that the brain circuitry is similar, too,” said Jarvis, an associate professor of neurobiology at the Duke University Medical School and an investigator at the Howard Hughes Medical Institute. “But we didn’t know whether or not those features were the same because the genes were also the same.”Now scientists do know, and the answer is yes — birds and humans use essentially the same genes to speak.

After a massive international effort to sequence and compare the entire genomes of 48 species of birds representing every major order of the bird family tree, Jarvis and his colleagues found that vocal learning evolved twice or maybe three times among songbirds, parrots and hummingbirds.

Even more striking is that the set of genes involved in each of those song innovations is remarkably similar to the genes involved in human speaking ability.

If you’re already thinking “This isn’t ‘convergent evolution,’ it’s common design,” you haven’t seen the best part yet. Science Daily goes on:

One of the Dec. 12 papers in Science found there is a consistent set of just over 50 genes that show higher or lower activity in the brains of vocal learning birds and humans. These changes were not found in the brains of birds that do not have vocal learning and of non-human primates that do not speak, according to this Duke team, which was led by Jarvis; Andreas Pfenning, a graduate of the PhD program in computational biology and bioinformatics (CBB); and Alexander Hartemink, professor of computer science, statistical science and biology.”This means that vocal learning birds and humans are more similar to each other for these genes in song and speech brain areas than other birds and primates are to them,” Jarvis said.

These genes are involved in forming new connections between neurons of the motor cortex and neurons that control the muscles that produce sound.

The Science paper puts it this way:

More than 50 genes contributed to their convergent specialization and were enriched in motor control and neural connectivity functions. These patterns were not found in vocal nonlearners, but songbird RA was similar to layer 5 of primate motor cortex for another set of genes, supporting previous hypotheses about the similarity of these cell types between bird and mammal brains.(Pfenning et al., “Convergent transcriptional specializations in the brains of humans and song-learning birds,” Science, Vol. 346: 1256846-1 – 1256846-13 (December 12, 2014). )

So certain birds and humans use the same genes for vocalization — but those genetic abilities are absent in non-human primates and birds without vocal learning? If not derived from a common ancestor, as they clearly were not, how did the genes get there? This kind of extreme convergent genetic evolution points strongly to intelligent design.

The rest of the article talks about the conclusions of the study authors – they think it’s a huge problem – and it is.

I hope you’re all beginning to see why I love birds so much. I just adore them. In fact, I am excited about them right now, and will probably appear silly by gushing about how great they are. Fortunately, my editorette is not hear to stop me!

Birds are not just a living disproof of naturalistic evolution. They are also loveable and adorable. (Especially parrots, of course) If you guys are considering a pet, go out and get yourself a cockatiel, if it’s your first bird, or a green-cheek conure, if you’ve had birds before. Just remember that they live 20-25 years, so you have to be ready to face responsibilities, expectations and obligations if you make a commitment like that. And you know what? That is totally awesome, to have someone to care about. It’s good stewardship to care for animals. And if you can’t commit to a parrot of your own over the long haul, then put out an additional bird feeder this winter, and vote against wind power. Wind power kills birds, and I hate it.

Also, that bird in the Evolution News post is an Indian ringneck parrot. And they are awesome!!!!

More posts on convergence

Stephen C. Meyer lectures on intelligent design and the origin of life

A MUST-SEE lecture based on Dr. Stephen C. Meyer’s book “Signature in the Cell“.

You can get an MP3 of the lecture here. (30 MB)

I highly recommend watching the lecture, and looking at the slides. The quality of the video and the content is first class. There is some Q&A (9 minutes) at the end of the lecture.

Topics:

  • intelligent design is concerned with measuring the information-creating capabilities of natural forces like mutation and selection
  • Darwinists think that random mutations and natural selection can explain the origin and diversification of living systems
  • Darwinian mechanisms are capable of explaining small-scale adaptive changes within types of organisms
  • but there is skepticism, even among naturalists, that Darwinian mechanisms can explain the origin of animal designs
  • even if you concede that Darwinism can account for all of the basic animal body plans, there is still the problem of life’s origin
  • can Darwinian mechanisms explain the origin of the first life? Is there a good naturalistic hypothesis to explain it?
  • there are at least two places in the history of life where new information is needed: origin of life, and Cambrian explosion
  • overview of the structure of DNA and protein synthesis (he has helpful pictures and he uses the snap lock blocks, too)
  • the DNA molecule is composed of a sequence of proteins, and the sequence is carefully selected to have biological function
  • meaningful sequences of things like computer code, English sentences, etc. require an adequate cause
  • it is very hard to arrive at a meaningful sequence of a non-trivial length by randomly picking symbols/letters
  • although any random sequence of letters is improbable, the vast majority of sequences are gibberish/non-compiling code
  • similarly, most random sequences of amino acids are lab-proven (Doug Axe’s work) to be non-functional gibberish
  • the research showing this was conducted at Cambridge University and published in the Journal of Molecular Biology
  • so, random mutation cannot explain the origin of the first living cell
  • however, even natural selection coupled with random mutation cannot explain the first living cell
  • there must already be replication in order for mutation and selection to work, so they can’t explain the first replicator
  • but the origin of life is the origin of the first replicator – there is no replication prior to the first replicator
  • the information in the first replicator cannot be explained by law, such as by chemical bonding affinities
  • the amino acids are attached like magnetic letters on a refrigerator
  • the magnetic force sticks the letters ON the fridge, but they don’t determine the specific sequence of the letters
  • if laws did determine the sequence of letters, then the sequences would be repetitive
  • the three materialist explanations – chance alone, chance and law, law alone – are not adequate to explain the effect
  • the best explanation is that an intelligent cause is responsible for the biological explanation in the first replicator
  • we know that intelligent causes can produce functional sequences of information, e.g. – English, Java code
  • the structure and design of DNA matches up nicely with the design patterns used by software engineers (like WK!)

There are some very good tips in this lecture so that you will be able to explain intelligent design to others in simple ways, using everyday household items and children’s toys to symbolize the amino acids, proteins, sugar phosphate backbones, etc.

Proteins are constructed from a sequence of amino acids:

A sequence of amino acids forming a protein
A sequence of amino acids forming a protein

Proteins sticking onto the double helix structure of DNA:

Some proteins sticking onto the sugar phosphate backbone
Some proteins sticking onto the sugar phosphate backbone

I highly, highly recommend this lecture. You will be delighted and you will learn something.

Here is an article that gives a general overview of how intelligent design challenges. If you want to read something more detailed about the material that he is covering in the lecture above related to the origin of life, there is a pretty good article here.

UPDATE: There is a good breakdown of some of the slides with helpful flow charts here on Uncommon Descent.

Positive arguments for Christian theism