Convergent Evolution Found in Poison Frogs

LiveScience ^ | 8/9/05 | Bjorn Carey

[RightWingAtheist]

Amphibious ping.

[ZULU]

Ribbett. Ribbett.

Just because something looks obvious, doesn't means it looks obvious. Like maybe 2 plus 2 equals 4 is merely an illusion.

[csense]

You don't need to have the mutation occuring to a large number of frogs for it to have a fairly quick effect on the ratio. Assume for a moment that it occurs with just one frog, and assume that the mutation is carried over to successor generations (a very simplified term would be a 'dominant' trait). Poisonous frogs tend to lay anywhere from 10 to 100 eggs in one shot, though this can vary with different species. (some frogs lay as many as 25,000 eggs at one time) At this rate, it doesn't take many generations before you have a large number of frogs descended from the original one with the mutation. With their advantage in terms of the food supply (they can eat more things, especially when food is abnormally low), it's easy to see how they can begin to overtake the non-mutants.

Sounds reasonable in theory, but then we're assuming ideal conditions.

We would need to plug in other factors such as pathogens, predators, and any number of environmental conditions that would be deleterious to the frogs survival, and especially to the young offspring.

Given random mutation, I think you have a possible theory, but I personally don't think you have the numbers on your side when we think of the practical, rather theoretical.

I can't argue the particulars of such things since I'm neither a biologist, or mathematician, but I think it presents a tremendous hurdle to explain the precise details for any given single lifeform to achieve this profound state that we we see these frogs in now, compared to what we think they were before that.

It is a fact that these frogs exist right now, but that existence per se does not infer that evolution must be the cause. That's something that needs to be specifically explained, and in detail, to rise from just simple conjectures.

(me) "This suggest an event of mutation that, although possible, is completely random, and unrelated to the ingestion of the ants."

(you)Of course; anything else would imply a will behind the mutation, guiding it to a specific purpose.

I'm glad you brought this up, because that is exactly what seems to be the case when considering the emergence of skin coloring.

From the article:

Also, both the frogs in South America and Madagascar evolved to have "don't-eat-me" skin colorings, the final step in a remarkable tale of multi-step convergent evolution.

This trait, which we also see in other species, seems to suggest a singular purpose for an event which is yet to happen.

I'm sure that science can deduce the physical processes that cause the pigments themselves, but what about it's purpose. How does science explain that.

By the way, thanks for giving a reasoned, well thought out response. It's good to have a real discussion on these threads every once in a while. :-)

Careful....you're fraternizing with the enemy here :-)

[malakhi]

Like maybe 2 plus 2 equals 4 is merely an illusion.

2+2=4 only within certain algebraic systems.

[Asphalt]

Somehow what you described sounds a whole lot more plausible than the fact that goo sat around for a few million years and then slowly turned into frogs.

[newsgatherer]

extensive? YES, convincing? NO!

Jake

[qam1]

Birds, lizards & spiders see color.

Plus it's probably more the contrast in colors that serves as a warning than the color itself

[NJ_gent]

"We would need to plug in other factors such as pathogens, predators, and any number of environmental conditions that would be deleterious to the frogs survival, and especially to the young offspring."

A mutation having a severe negative effect on the frogs would tend to cause those carrying the mutation to die out rather than breed. Ergo, it's not much of a stretch to assume that the trait of immunity to poison came with no significant drawbacks. In other words, we can rationally assume that the frogs without the immunity differed from the frogs with the immunity only by the immunity trait itself. That seems logical, especially since interbreeding would be required to carry the trait onward. In that case, you have two groups of frogs, one which can eat certain insects, and another which can eat the same things plus these poisonous ants. That gives them an advantage, especially in cases where the usual supply of food is low.

"Given random mutation, I think you have a possible theory, but I personally don't think you have the numbers on your side when we think of the practical, rather theoretical."

When we're talking about millions of frogs over hundreds of generations, how is it so difficult to see how a single particular mutation could not occur? Just from a statistical standpoint, it doesn't appear, on its face, to be so very improbable. Amphibians are simple enough that their DNA can sustain a more changes than higher lifeforms without serious consequences.

"I think it presents a tremendous hurdle to explain the precise details for any given single lifeform to achieve this profound state that we we see these frogs in now, compared to what we think they were before that."

Absolutely, it does. Ideally, we'd have samples of DNA from each species in between modern frogs and their common ancestor. Of course, DNA degrades very easily, so we're left with the good 'ol fossil record. That gives us imperfect knowledge, which leads to sometimes imperfect theories about the steps getting from point A to point B.

"It is a fact that these frogs exist right now, but that existence per se does not infer that evolution must be the cause."

Right, but when you have A, B, C, and D a few million years back in the fossil record but not today, and X, Y, and Z around today, but not a few million years back in the fossil record, your only two choices are that new species are popping out of thin air, or that species are changing over time.

"I'm glad you brought this up, because that is exactly what seems to be the case when considering the emergence of skin coloring.
From the article:
Also, both the frogs in South America and Madagascar evolved to have "don't-eat-me" skin colorings, the final step in a remarkable tale of multi-step convergent evolution. This trait, which we also see in other species, seems to suggest a singular purpose for an event which is yet to happen. "

I think comment #40 addressed this issue better than I did and better than the article. Either seem plausible, but his thoughts seem moreso to me.

This is, of course, all very simplified. I'm sure that someone who's spent a lot of time dealing with these frogs would have some fascinating insights into the DNA-based evidence for these findings. I just don't have the time or energy to sift through the interweb to find such obscure information.

[News Junkie]

Hi Zulu.

Nice condecension and non-sequitur. Covergent evolution of ants and frogs, as described in the article, looks obvious? As obvious as 2+2=4?

[qam1]

Evolution - the deeply-held belief that astronomically improbable events occur repeatedly

The ants are poisonous because of a plant they eat.

So are we to believe that the plants, two ants & two frogs all just happen to make it to the same place in South America from Mt. Ararat after the flood? As well as different plants, ants & frogs just happen to make it to the same place in Madagascar. Not to mention that the ants wouldn't poisonous until they got to the location so then the frogs wouldn't be poisonous either and their bright colors would make them easy pickings.

Talk about an astronomically improbable event

[ZULU]

I think so. But then I'm a biologist.

[News Junkie]

Ouch! The trump card.

Okay, I'm in over my head as a layman. So, for the time being, I'll slump back to unqualified comments on politics. :)

Although, I still think that you guys play to loosely with extrapolating links just because they had to have happened for the "discovery" to be right. My opinion.

[Soliton]

<"Somehow what you described sounds a whole lot more plausible than the fact that goo sat around for a few million years and then slowly turned into frogs"

Thank you! You are correct! The observed clouds of organic chemicals billions of light years away were placed there by Satan to make us think that Bishop Usher was wrong. The Universe was created 6000 years ago. The Murchison asteroid containing amino acids is a trick of the anti-christ, and the Earth is flat with four corners and Jerusalem is the center of the universe. Disease is caused by evil spirits.

[Asphalt]

Uh. Is that supposed to be funny?

[trebb]

So your objection to evolution can be stated as "Sure dogs came from wolves, and cows came form aurochs, and even birds came from dinosaurs, but people are special, we are sentient."

No, my objection to evolution is that God made us separately and apart from the animals and pays us special attention. I doubt that the animals can be explained by evolution, but it would not be bothersome to me to find that they have evolved in some fashion during our time on the planet - Man has done some purposeful breeding to change the forms of numerous animals.

[trebb]

Does that include the appendix? Vestigial tailbone? Seems like either God isn't designed very well or the duplication process needs work...

God made us exactly as he wanted to make us and even started out with a long-living version, but we didn't deserve that kind of life span. All the parts are as He decided they should be and serve the purpose He designed them for. The appendix still serves a purpose and putting the word "vestigal" before tailbone stil doesn't give us tails. Mayube this will interest you (or maybe not)

The human appendix—once scorned by evolutionists as a useless ‘vestigial organ’—long ago earned the respect of medical doctors. Unfortunately, this truth has not filtered down to textbooks and the popular press. Just recently, the Associated Press distributed an article to US newspapers on the appendix 1, warning readers that doctors often misdiagnose other ailments as ‘appendicitis’ and opt for removal. (A major study found that 15% of removed appendixes were normal.)

The AP article reinforced the persistent belief that the appendix is a useless organ, leftover from our evolutionary past, by claiming ‘the appendix … has no real function.’

We all might be dead, in fact, if we were born without an appendix.

You see, the appendix is a highly specialized organ with a rich blood supply, not what you would expect from a degenerate, useless structure. It has long been known that the appendix contains lymphatic tissue and has a role in controlling bacteria entering the intestines (see Frederic H. Martini, Fundamentals of Anatomy and Physiology, 1995).

A clue to the appendix’s function is its strategic position where the small bowel meets the colon. The colon is loaded with bacteria that are useful there, but which must be kept away from other areas. The appendix’s main role is likely to be in early childhood (see ‘Your Appendix: It’s there for a reason’). The organ’s highly concentrated lymphoid follicles, which play an important role in the immune system, develop about two weeks after birth—at the same time that the colon begins to be colonized with the necessary bacteria.

At one time evolutionists postulated there were 180 ‘vestigial’ structures in the human body. Today this list has shrunk to virtually zero. No organ should be removed without good reason!

For in-depth information, please read ‘The Human Vermiform Appendix—a General Surgeon’s Reflections.’

Good Day

[DouglasKC]

First, species of ants high in alkaloids had to evolve on two separate continents.
"The ants had to be there with alkaloids for the frogs to evolve to get alkaloids in their skin," Clark told LiveScience.
Then the frogs had to develop a resistance to the alkaloids--instead of spitting out the ants or passing the alkaloids through their systems, the frogs became able to keep their ant dinners down. Then they evolved to make use of the alkaloids themselves.
Also, both the frogs in South America and Madagascar evolved to have "don't-eat-me" skin colorings, the final step in a remarkable tale of multi-step convergent evolution.

Hilarious scenario. All those frogs eating poisonous ants despite getting sick and possibly dying througout the eons knowing that their sacrifice will make it possible for their ancestors to have poisonous secretions in the future. And not just in one place on earth...but two! Never have so many sacrificed so much for so many.

[Reconray]

I'm curious...Who informed the frogs that the ants were poisonous?

[skr]

First, species of ants high in alkaloids had to evolve on two separate continents. Why? France colonized Madagascar and some of South America. Is it not worth considering a possible migration of both the ants and the frogs via French shipping?

[blowfish]

God made us exactly as he wanted to make us and even started out with a long-living version, but we didn't deserve that kind of life span.

So we are *not* made in god's image. We used to be, but now we are some sort of cheap knock-off at this point. There's no telling what could happen in such a degraded form! Perhaps we even subtly change from generation to generation, no longer rigidly adhering to the original blueprint.

Personally, I think the whole garden-of-eden/god's-punishment-by-inventing-burst-appendices is a load of horse-hockey, but to each his own.