Are you an atheist?

[Mike375]

I don't think it's really necessary to explain every variation in every species and their ancestors as well as their descendants - as long as the overall process is accepted and comprehended. Getting from one number of belly scales to another - or exactly detailing all the morphological differences between ancestral species and modern ones may be of interest to zoologists and paleontologists, but for most people an understanding of the overall process is what's important. Nothing you've stated about snakes and lizards negates any principles of natural selection so I don't see where it's full of holes.
Another thing - when you speak of "transitional species" - we're all transitional species, undergoing an extremely slow process that can't be observed except through the passage of time, the minuscule variations from generation to generation, and the process of adaptation.

The transition is easy enough to accept with animals that remain basically the same. From some form of monkey to human is a journey that is nothing compared to lizard to snake or from spawn to the amniote egg.

Edit: You mention "as long as the overall process is accepted and comprehended". Have you considered the possibility that there is more than one process, that is, evolution might in fact come about by more than the one means that is put forward.

 

[Libre]

You mention "as long as the overall process is accepted and comprehended". Have you considered the possibility that there is more than one process, that is, evolution might in fact come about by more than the one means that is put forward.

I would entertain any rational explanation for pretty much anything.

 

[Galaxiom]

what are your views on the intelligent design people's pin up star, the Bombardier beetle.

A fascinating organism indeed but definitely not a point scorer for creationists.

The intelligent design argument has since been so thoroughly debunked that it is hard to find a creationist site among the vast numbers debunking it. The original proponent couldn't even get the description of the chemistry right and every creationist site I found that went into any detail repeats the same error which had been pointed out at least as early as 1981.

Covered pretty well here.

 

[Mike375]

The intelligent design argument if true would mean a God or gods with limitations.

The only intelligent design argument I could accept would be if God or gods simply laid out the laws of nature then let nature take its course. However, that would still indicate a God with limitations.

In many ways I see evolution as being similar to astronomy before satellites etc. By that I mean it is roughly right but missing a lot of stuff.

 

[Galaxiom]

In many ways I see evolution as being similar to astronomy before satellites etc. By that I mean it is roughly right but missing a lot of stuff.

What kind of things do you have in mind?

Sure there are gaps in evidence for the precise sequences of changes and no doubt there will be more refinement as new genetic and fossil evidence is found but the fundamental concepts of diversification though inheritable mutation and natural selection are rock solid.

These processes are all that are required to explain how life progressed from the first simple replicating molecular structures to what we see today. Adding any further mechanisms is superfluous.

 

[Mike375]

What kind of things do you have in mind?

Sure there are gaps in evidence for the precise sequences of changes and no doubt there will be more refinement as new genetic and fossil evidence is found but the fundamental concepts of diversification though inheritable mutation and natural selection are rock solid.

These processes are all that are required to explain how life progressed from the first simple replicating molecular structures to what we see today. Adding any further mechanisms is superfluous.

Don't really know

As I posted earlier more recent thinking is small theropods descended from flightless birds....quite a change

I can accept in general principle your outline of the lizard getting to 100s of vertebrae. However I just can't see that happening.

As I said before my own feeling is there were many many starting points. I do believe if the conditions for life exist then life will commence. In fact I can't see it not happening. To me it is as simple as placing containers full of petrol all over the place....then a bolt of lighting or whatever will set one off. Actually over time a lot of the containers will catch fire.

In the case of getting from spawn to amniote egg my feeling is that situation did not occur. In other words I don't think the reptile developed from an amphibian. The reptile was on a different railway line.

It has been mentioned that the various life forms whether fish, amphibian, snake, lizard, bird and mammals have an overall similarity. That to me does necessarily indicate a common starting point. Rather, the various species have overall similarities because they are the forms that will exist with conditions provided by the earth.

Think of it like different racing cars such as NASCAR, Indy Car, F1, Sprint Cars, V8 Supercars etc. they all have an overall similarity and that is simply because that is forced on them by the form of racing tracks. However, if we take a Top Fuel dragster it is totally different and that is because of the track where they race. In other words if there were no drag strips then a Top Fuel dragster would not have "evolved" or if it evolved it would die out.

When I was just a teenager my father said to me one day that I would die wondering My maternal grandmother used to call me Doubting Thomas.

 

[Galaxiom]

As I said before my own feeling is there were many many starting points. I do believe if the conditions for life exist then life will commence. In fact I can't see it not happening. To me it is as simple as placing containers full of petrol all over the place....then a bolt of lighting or whatever will set one off. Actually over time a lot of the containers will catch fire.

You have to remember that what we think of as multicellular life only began about 550 million years ago after a period of about seven times as long where only single cellular organisms existed.

If there were multiple starting points for life those other than the organisms on our tree died out because every living thing including all microorganisms shows a relationship among their genes that indicates they shared a common ancestor. I suspect if there were any alternative branches of life they were abruptly wiped out in the great oxygenation when photosynthesis was introduced.

The giant leap that introduced the possibility of macroscopic organisms was the Eukaryote cell with respiratory system of the mitochondria organelle. This is an evolutionary bottleneck places all macroscopic organisms firmly on the same branch of the tree of life.

To consider that Amphibia and Reptilia had completely different beginnings is a long way from plausible.

 

[Mike375]

To consider that Amphibia and Reptilia had completely different beginnings is a long way from plausible.

You can have them on your tree of life but their starting points were much closer to the root of the tree.

In some ways I see the amphibian as similar to the legless lizard in the sense they are a dead end.

Anyway that will do me for now as I think the time is rapidly approaching for some alcoholic beverages.

All the best to you and yours for the new year.

 

[The_Doc_Man]

It is my understanding (which could be wrong) that evolution does not have a goal.

It IS wrong. Evolution has a goal. It is that things survive. If things don't survive, they don't reproduce and that branch of evolution dies out. Evolution is all about rolling the dice to see which combinations work (better) and which ones don't. The goal? Selection of the best combination of characteristics. It doesn't matter how subtle the differences are between different combinations. The ones that survive better will be selected (actually, HAVE been selected).

However, I have to admit that I allowed a verbal inaccuracy to creep in because otherwise we could never actually talk. Too many people tend to freak out on being excessively precise. So I used colloquial terms first. But now, the pedant steps out...

What is the goal of evolution? Technically, it has no goal - because only sentient beings have goals. Evolution has tendencies or trends or influences. You might ask what is the goal of gravity? Or perhaps what is the goal of the stellar phoenix cycle (stellar fusion) that powers all stars? Do they have goals? No - for they are inanimate forces.

There is also the question as to whether:

evolution might in fact come about by more than the one means

Ah, but technically, that is a problem in reductionism vs. wholism - it is ALL evolution. It is just that multiple mechanisms are involved. Random mutation is a factor - albeit not one of the bigger ones. Subtle differences brought about by "rolling the dice" to just get another combination (a.k.a. genetic shuffling through bisexual reproduction) will find many combinations and will (excruciatingly slowly) purge a species of its bad recessives.

Sometimes, it is changing environment that brings about changes. Do a web search of the NY Times on the Web from about two to three years ago for the evolution of humanity in the form of improved lung capacity for Sherpa mountain guides in the region of the Himalayas. That change has occurred in modern man, brought about by their choice to live in a thin-air environment. Read the article. Don't take my word for it.

 

[Mike375]

Doc

By goals I mean (as I think others do) that buried inside some lizard something says "I need to grow longer and powerful back legs and a longer tail so I can run bipedal at high speed"

Myself and others with similar views don't have any issues with gradual change of species.

In my opinion the mistake people such as yourself and especially Galaxiom is to act as if people like me who have major issues with macro evolution have divine intervention as our answer.

I posted earlier about what I call the "born gain evolutionists" and born again Christians being the same, it's just the words change. The common point is either group appear to have no acceptance of the possibility of an "in between" view or some variation of the theme.

Galaxiom earlier posted an outline of how he thought the lizard thorax could over time change to a snake thorax and said that sounded reasonable. However, he left out the big one and that is the skull/jaws situation. Survival through that transition would be really something.

With respect, you blokes are like someone measuring the size of a brick or a stone using a micrometer As I posted earlier recent thinking is small theropods descended from flightless birds and that is about a 100% turnaround.

 

[The_Doc_Man]

Mike, that's just it. THERE ARE NO GOALS for each species. The thrust, the direction if you prefer, for evolution is that bad changes usually tend to die off, good changes usually tend to survive, unless there is an environmental catastrophe to "change the rules" suddenly and without enough time for the superior variant to establish itself. The lizard didn't have a goal of growing ANYTHING. But the ones who DID make that change had a better chance of survival and so perpetuated that change.

We don't measure bricks with a micrometer. But sometimes we DO measure the depth of a layer of soil deposition using fairly fine measurements because that is key to making an educated guess of the age of what was underneath the deposits.

If you accept macro evolution, well and good for you. It is a reasonable choice. There are those (and I'm sure you've seen some of them in this very thread) who would vehemently disagree.

As to a variety of mechanisms, OF COURSE evolution works in more than one way. I was merely pointing out that the word evolution DOES NOT mean "survival of the fittest." However, considering the things that evolution covers, one of them IS "survival of the fittest." Mutations and adaptation to change are also part of the picture. To say that there is more at work than just evolution is similar to saying that there is more than one type of thermodynamics. It's ALL about energy flow for thermodynamics, whatever kind of energy you've got, just as it's ALL about differentiation of species in whatever way it happens under evolution.

By the way,

In some ways I see the amphibian as similar to the legless lizard in the sense they are a dead end.

if you've never had deep-fried south Louisiana frog legs, you don't know much about amphibians. But of course, that leads to legless frogs, doesn't it...

 

[Galaxiom]

You can have [reptiles and amphibians] on your tree of life but their starting points were much closer to the root of the tree.

In some ways I see the amphibian as similar to the legless lizard in the sense they are a dead end.

This post strongly suggests that you are still stuck in the mistake of comparing the living forms of reptiles and amphibians. Reptiles certainly did not evolve from animals that resembled today's amphibians.

Modern amphibians are descendants of just part of the range of amphibians that existed during the time when tetrapods diverged to become the ancestors of modern amphibians and the amniotes. The reptile-like amphibians of the time were subsequently completely supplanted by the amniote forms which were much better adapted to life on land.

Evolution of the tetrapods was not an overnight event. Lobed fin fish living in the shallows diverged into a number of groups that increasingly became able to cope with a terrestrial environment.

Unfortunately, like many of the rapid diversifications in paleohistory , the most rapid evolution of the tetrapods occurred during times of great extinctions when very few fossil specimens have been found.

 

[Galaxiom]

By goals I mean (as I think others do) that buried inside some lizard something says "I need to grow longer and powerful back legs and a longer tail so I can run bipedal at high speed".

To gain the slightest credibility for this suggestion you would have to demonstrate a place where primitive organisms could manage to contemplate such a subjective analysis and a plausible mechanism for how that would influence mutation and/or selection of the successfully reproducing gametes.

Fact is, such suggestions can be eliminated using Ockham's Razor since the proven mechanisms of random mutation and natural selection can already fully explain the diversification of species.

The is no evidence whatsoever for "goals" in Evolution.

 

[Alc]

To gain the slightest credibility for this suggestion you would have to demonstrate a place where primitive organisms could manage to contemplate such a subjective analysis and a plausible mechanism for how that would influence mutation and/or selection of the successfully reproducing gametes.

Fact is, such suggestions can be eliminated using Ockham's Razor since the proven mechanisms of random mutation and natural selection can already fully explain the diversification of species.

The is no evidence whatsoever for "goals" in Evolution.

I once had a (brief) conversation with a friend of my wife. She (the friend) teaches science in high school, here in Ontario and is also a regular church-goer. Knowing I was an atheist, she asked me "If evolution is true, how come I can't evolve more money? I need that." I assumed she was joking, so I laughed. She wasn't. I started to say that evolution doesn't work by something/somebody consciously deciding they need something and just getting it, but as that was how she understood it and as there was no getting around the fact, I ended the conversation. I think we both parted ways believing that if only the other person could just listen to reason he/she would change their mind.

 

[The_Doc_Man]

Damn, I need to work on evolving that money tree to be more efficient. I must be doing something wrong...

 

[Mike375]

You blokes did not correctly read....I said it was my understanding goals were not involved in evolution.

This line was to illustrate what I meant by goals.

"By goals I mean (as I think others do) that buried inside some lizard something says "I need to grow longer and powerful back legs and a longer tail so I can run bipedal at high speed".

So to be doubly clear it is my understanding the above is not involved with evolution.

 

[Mike375]

This post strongly suggests that you are still stuck in the mistake of comparing the living forms of reptiles and amphibians. Reptiles certainly did not evolve from animals that resembled today's amphibians.

No, I am not stuck there at all.

But surely you are not suggesting evolution has come to an end in the past few million years or so?

My basic issue is the transition period, although I have an argument (and example) against my own point of view.

I have already posted I thing the legless lizard is a dead end. I also think monitor lizards are dead ends.

The monitors (and I have kept them) are very interesting. The Jacobson's organ and forked tongue is at the full snake level. With other lizards it is barely functional and the tongue is not forked but often has a V at the end.

The monitors also have a small degree of lower jaw detachment but compared to snakes is nothing. The monitor lizard still maintains a very strong bite force, I can attest to personally, although while wearing heavy gloves. On the hand the snake must have about the weakest bite of any animal for equal head size.

In other words the monitor gained some snake advantages but was stopped short. The only was a monitor could change to snake type jaws and survive would require some type of mutation or whatever other means that would allow the transition to be very quick.

The monitors also have venom but compared to snakes it could be rated as bordering on non function. Even if a potent venom developed it needs the snakes skull for delivery.

HOWEVER......transition over a long period could be possible if conditions existed (especially competing predators) whereby the competition was of no significance. One particular monitor, the Komodo Dragon, is a good example.

There are a couple of major differences between Komodos and other lizards and especially other monitors and these are important. Firstly, unlike other lizards and monitor lizards the Komodo takes prey that is large and of often much larger than itself. As I sure you are aware this is due to the nature of the septic bite and also a very slashing bite with one bite prey will bleed out.

Another difference compared to other monitors the Komodo, except when juvenile, is not a climber. Other monitors will go up a tree like a lightning bolt.

In size we could say a good size male Komodo will be about the weight of a leopard. However, if all the Komodos could be replaced by leopards or other similar size mammal predators they would not survive due to the relatively small food supply in the areas Komodos occupy. In fact the Knomodo is a great example of island gigantism.

Apart from lack of climbing as compared to ther monitors it is basically slow and clumsy.

So let's now assume we let a lot of Komodos do a trip to Africa. They would be in deep shit. On the larger prey they could still do their bit but taking a couple of days and more for the animal to die, by the time the Komodo (and its mates) got to the dead animal there wold be nothing left as the lions, hyena, vultures and whatever else would have disposed of it.

The Komodo would also be in deep shit if it went the normal lizard way, that is, prey that is basically crushed and killed in one go. The Komodo lacks the speed. Also, a monitor favourite is going up a tree and cleaning out the bird's nest, whether the nest have eggs or hatchlings and clean up mummy bird if it wants to mount a rescue mission.

Thus in short, a "normal monitor" was able to transition/evolve to a Komodo because of the unique conditions where the Komodo lives.

To my knowledge, prehistoric monitors of 20 feet and probably a ton or more in weight are restricted to Australia. Such a giant version of a Komodo was probably OK because of a lack of competing predators.

But at this stage of the game my basic belief is the start of life was very wide spread and there were lots of evolution "trees" but my "trees" would have more branches that were shorter. In other words lots of dead ends.

You previously argued against that on the basic of the general common ground across the whole animal range. However, as I posted earlier that commonality would be a result of surviving/developing within the confines caused by the earth.

I used the analogy of racing cars. Whether Sprint Cars, Formula 1, Indy Cars, NASCAR, V8 Supercars there is a lot of common ground and that common ground comes about because racing car tracks consist of corners and straights.

However, the Top Fuel dragster has almost nothing in common with the other except for internal combustion engine and driving through the rear wheels. That Top Fuel dragster would had never evolved unless there were drag strips. Its "evolution" has been due to the confines of only doing a 1/4 mile acceleration run and in a straight line.

 

[Mike375]

Just to throw something else into the pot. Does devolve or devolution happen. I think I read our appendix have lost the ability to whatever it was they did and we can no longer move our ears.

This is something that has always fascinated and puzzled me with the reptile. Consider the following if you will.

1) As a predator (and especially the snake) the success rate they have or strike rate they have in terms of attempts made to prey caught is extremely high. I don't have any numbers and probably no one else has but their success rate is way out of the league of the feline or dog.

2) Their ability to eat huge amounts in single sessions or short periods is huge. For example a monitor and house cat of the same approximate weight the monitor's capacity to down food simply is in another league.

3) Their general long thin build, low to the ground and limbs that will fold against the body (snake of course is the king here) also means they can pursue prey where a mammal predator of the same weight simply can't go.

So.....we have a predator with an extremely high success rate in obtaining food and the ability to consume huge amounts as a percentage of its body weight.

In addition when it comes to scavenging it is tops here as well. I can tell you from first hand experience/experiments that a monitor will take meat (that is off shall we say) that is well past the used by date for a cat or dog.

HOWEVER.....this same animal has food requirements, when measured over the year, that are incredibly small as compared to a mammal predator of the same weight.

The whole situation seems like one big conflict.

 

[Galaxiom]

Does devolve or devolution happen. I think I read our appendix have lost the ability to whatever it was they did and we can no longer move our ears.

This is still Evolution. If the resources required to grow a feature exceed the benefits then the feature may be lost. Some animals even lost much of their ancestors brain capacity for this reason.

This is something that has always fascinated and puzzled me with the reptile. Consider the following if you will.

1) As a predator (and especially the snake) the success rate they have or strike rate they have in terms of attempts made to prey caught is extremely high.

2) Their ability to eat huge amounts in single sessions or short periods is huge.

3) Their general long thin build, low to the ground and limbs that will fold against the body (snake of course is the king here) also means they can pursue prey where a mammal predator of the same weight simply can't go.

4)when it comes to scavenging it is tops here as well.

5) this same animal has food requirements, when measured over the year, that are incredibly small as compared to a mammal predator of the same weight.

The whole situation seems like one big conflict.

Why the perception of conflict? All these features allow the animal to survive in very sparse conditions.

This is why these reptiles survived the Cretaceous-Palaeogene impact winter.

 

[Mike375]

This is still Evolution. If the resources required to grow a feature exceed the benefits then the feature may be lost. Some animals even lost much of their ancestors brain capacity for this reason.

Fair enough.

I assume the reptile has retained the survival system through to today because it enables it to live and thrive in extremes. There are plenty of parts in the world where life is plants, insects (which are cold blooded) and reptiles and mammals/birds are not much more than passing visitors

There is an interesting situation with insects and reptiles. I sure can appreciate that someone who has been a reptile keep also has had a lot of exposure to insects.

In some ways the insect predator is like the high performance mammal/bird predator in the sense that it does not take much "damage" to result in the insect predator being unable to survive and in fact they can just die as a result of the injury. However, the reptile is quite the opposite, it takes a lot of severe permanent disability to bring them to an end. However, I am guessing the insect/spider makes up for this by the huge number produced with their reproduction.

As a side note and with respect to the balance of nature, back around the 1960/70s or so the Florida Everglades experienced a great increase in mosquito numbers which at the time caused much puzzlement. The problem was the American Alligators were almost shot out for the skin trade. The result of this were beavers and their dams because alligators would simply swim through the dams and knock them down etc. However, when the alligator numbers went right down the beaver dams went right up and of course greatly increased the amount of stagnant water.