Where Evolution falls short - Please read first post

[ko ko]

it is also thought that the eye may have evolved in multiple instances due to the differences in the mammal eye as compared to other eyes such as the insect eye or the crustacean or mollusk eye (most specifically the squid)

[Tobias_Marco]

<The video the Current linked to said that only the Mantis can turn his/her head, so why aren't there more creatures that look very much like the mantis who can't turn their head?>
<Another thing is the eye, if you are right then the eye, being as complex as it is formed many times, without a designer.>
<From what I can tell complex things do not exists without a designer.>

[Blu]

Again, with the mantis example I must point out that your arguement is basically that two species have different features and that this is exactly what evolution predicts. If indeed the mantis is the only insect capable of moving its head, then it or its recent ancestors must have evolved said ability.

You ask 'what good is half an eye', but I must then ask: would you be better off being able to tell light from dark than not at all? Addressing the main idea of your point though, your arguement is flawed in that the premise that there must be a half-eye is incorrect. Nowhere is there a creature with a half-eye, but creatures with less specialised eyes.

The eyes of creatures likes humans and insects both rely on similar mechanisms, and likely all evolved from a common ancestor, for want of a better phrase. They all use similar photoreceptor cells, and even today we have creatures with simple patches of photoreceptors. The eye evolution is very well documented.

[Tobias_Marco]

<Very well.>
<Let me ask you this: If the largest stalagmite in the world is 62.2 metres (204 ft) high and is located in the cave of Cueva Martin Infierno, Cuba.

Spoiler:

Fothergill, A. et al. (2006) Planet Earth, London, BBC Books, pages 184-185

Then how long did it take to form?>

<There is a picture (published in the October 1953 edition of National Geographic) you can see a stalagmites that formed quickly. If you look closely you can see a bat encased in this structure. This stalagmite formed so quickly that the bat was not exposed long enough for it to rot away. This was discovered in Carlsbad Caverns, New Mexico. (Mason Sutherland, Carlsbad Caverns in Color, National Geographic, October, 1953, p. 442.)>

"How long does it take for a stalactite to grow? Many people, impressed by repeated statements of the extreme duration of geologic time, have made statements to the effect that it takes dripstone practically forever to grow appreciably. However there is more than a little evidence that growth is considerably rapid. First of all, stalactites are found in man-made tunnels that are only a few years old…. Second, certain conditions are so favorable to dripstone growth that as much as several cubic inches a year may be deposited in a single stalactite…. Third, there are many examples of large stalagmites growing on blocks of stone that have fallen from cave ceilings."
Hendrix, Charles E., The Cave Book (Revere, Massachusetts: Earth Science Publishing Co., 1950). p 26 (Taken from the book: "That their words may be used against them")

http://www.environmentalgraffiti.com/ne ... th?image=2

Hall of Giants, Carlsbad Caves, New Mexico
In Sequoia Caverns, stalactites protected from tourists from 1977-1987 grew 10 inches, or 1 inch per year. At this rate they could have grown 300 ft in just 3600 years.

Large Formation at the "Hall of Giants", 1942
Many caves do have slow stalactite and stalagmite growth rates today. However there is evidence which suggests that caves were formed rapidly by sulfuric acid dissolution rather than weaker and slower carbonic acid. This process would not only have sped up cave formation but also the growth rates of stalactites and stalagmites.

The Crystal King, the largest Stalactite in the Ohio Caverns, a show cave located 30 miles from Dayton, Ohio near West Liberty, in the United States.
The hydrogen sulfide could come from several sources, including anaerobic decomposition of organic matter, oxidation of sulfide deposits, volcanic activity and others. There are disputes galore about how long these incredible formations take to form, but in some instances it hardly seems to matter because they are so stunning to look at.

[Current]

<The video the Current linked to said that only the Mantis can turn his/her head, so why aren't there more creatures that look very much like the mantis who can't turn their head?>

My first guess, and do take into account I am not a biologist, when the mantis ancestors developed the ability to turn their heads, they beat those that could not in the competition for resources. Thus, proto-mantids that couldn't turn their heads died out.

Also, mantids reproduce sexually, so you'd have head-turners reproducing with non-head-turners (before speciation, anyway). That results in a mix of head-turner and non-head-turner offspring, but the latter die more, so over time the proportion of head-turners increases in the population.

All of the above is a first guess without any research on the evolutionary history of mantids, i.e. just a way it could have happened, not saying it's how it actually did happen. It's pretty much the basic concept of natural selection, you don't expect a perfect continuum of variations.

<Another thing is the eye, if you are right then the eye, being as complex as it is formed many times, without a designer.>
<From what I can tell complex things do not exists without a designer.>

Evolution pretty much says that accumulating small changes plus a selection process can result in complex (or complex-seeming) machinery with no designer intervention. If we accepted the premise that complexity equals design, we wouldn't be having this conversation.
Which is to say: I disagree, complex things without designers exist. If you want to use that argument, please take a step back and show why complexity equals design.

On the second post:
Stalactites can form quickly, therefore evolution is false? I'm missing something here.
(as an aside, not all stalactites are created equal, the speed depends on what it's made of)

[Tobias_Marco]

<It is one of the big problems that I have.>
<If the stalactites form at the speed that these do, then that means that the Earth would have to be a lot younger then evolution would have us believe.>

[Current]

That's under the assumptions that
a) all stalactites form at the same speed (false, see my post above or here)
b) the age of the oldest stalactites we've found provides the basis for reasonable estimation of the age of the Earth. As a matter of fact, they only provide a lower bound, i.e. the Earth certainly cannot be younger than the oldest stalactite on Earth, but there's no reason it can't be far older. Stalactites didn't start forming right away, those that formed before can get broken, and it's likely even bigger stalactites exist that we just haven't found because they aren't in accessible locations.

[Tobias_Marco]

<All VERY good points.>
<So tell me this: What is the age of the oldest stalactite known to human beings, and how do we know how old it is?>

[Current]

I could tell you there are stalactites about 250,000 years old, see here. Older than the Noachian Flood, dated with 3 different methods, none of them assumes anything about speed of formation.

But since I'm not a geologist, or particularly knowledgeable about stalactites, I don't know if those are old, young, or average, and I'd have to do some research to begin to get a general idea of what the oldest ages are. You're welcome to do this yourself, if you are truly curious.

[Tobias_Marco]

<Sadly it will not show me the whole article, and the abstract is hard to read, but I will look it over some more.>

and a-spectrometric U-Th age of not, vert, similar 255 ka.

U-Pb dating has no upper limit and, hence, materials of Quaternary age older than 0.6 Ma can be analysed to investigate landscape development, paleoclimate, hominid evolution or hydrogeochemistry in carbonate terrains.

<We seem to have 255000 year old stalactites. That is somewhat older then I say that the flood happened.>
<Given that I have already said that I believe that the Earth is about 6100 to 6500 years old.>