h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

"I don't see also how a small dinosar chasing flys is suddenly going to grow wings from this, as there is major difference between a bird and a dinosur."

But not all of them have to occur at once. Take archeopterix--it still had teeth, a bony tail, and heavy bones; but it had wings. It couldn't fly as well as today's birds, but it didn't have to if it merely glided from tree to tree or chased insects with short hops. One step at a time will eventually go from a small predatory dinosaur (alread light to be a fast runner) to a bird like those today.

You can't do it in one step though.

My point was that it is not a new species.

A fruit fly bombarded with radiation and mutated is still a fruit fly, just because it can't breed with none green glowing fruit fly's does not mean it is not a new species. It has the same DNA but the genes are arranged differently.

A goldfish has virtually the same DNA as a Cod but its genes are arranged slightly differently in sequence and so its different but still a fish.

Well what I'm saying is that while different variations of the same species and type can occur, actual new species's can not.

this is because there not really new species its just that the one suited to that enviroment have passed on those jeans making them more prominant than the other ones, making all the young different but still the same species.

Adib

Couldnt find anything useful about the fruit flies but this is fairly digestible.

http://www.cbs.dtu.dk/staff/dave/IconsReview.html

Well of course you can't have it happen in one step if evolution did happen.

Why does archeopterix having teeth prove its a dinosur. There is still two birds that have teeth today, or did one of them die out a couple of hundred years ago?

How did they know that archeopterix ould not fly well?

Plus its not one step is it, the dino's arms would have to start growing further up the body (Closer to the back than the front I mean), its fingers would have to enlongigate and there would have to be a sheath of skin attached to it all. Plus it would have to have a different type of wrist and bone structure to make even a fairly useless gliding wing.

Also archeopterix had more fingers than these dino that evolved in to them.

Also what about strenth, it takes a lot of energy and stamina to keep a wing extended, try holding your arms out for 10 mins.

Plus the muscles to be able to glide would have to be arranged differently than that in the dino's arms and if it wanted to falp then these redundent arms it did not really use would suddenly have to increase in muscle capacity.

How would its lung system change from that of a reptile to what we have now in birds to as it can't take stages to hange such vital organs.


I read some where that there was actually a flying reptile as they call them, found that was older than archeopterix and was actually around before some of the dino's they said evolved in to archeopterix like animals.

Adib

Hi Adib,

Thanks for replying, but I'm not sure you answered my question. I asked whether you could imagine, by pure chance, two "varieties" of one species not being able to breed, for whatever reason?


Here is a case where a fly that lives, courts, mates, defends and develops on the fruit of the hawthorn plant adapted to do the same on apple trees when they were introduced to North America in the mid-1850s. (here's a nice summary: http://www.sciencecases.org/maggot_fly/maggot_fly.asp )

Natural selection has adapted the fly to be in sync with the fruiting of the hawthorn, so that their larvae can grow inside the fruit, using it as raw material.

Apples have different fruiting times, about 6 weeks earlier. Some of these flys moved to the apple trees to take advantage of this new opportunity (new "ecological niche"), and again natural selection selected the individuals that matched the emergence of adults from larvae with the apple fruiting time (see the graph in the above link).

"So what?" you might be asking. Well, the thing is that these two "varieties" are never breeding at the same time anymore, they never come into sexual contact with each other. That is the definition of a species. Two new species have arisen from one and we have witnessed it. After over 100 years of speciation, there are now physical differences between the two new species.

Here is the reference to the paper, it's a classic: Bush, G.L. 1969. Sympatric host race formation and speciation in frugivorous flies of the genus Rhagoletis (Diptera: Tephritidae). Evolution 23:237-251.

Notice the date. There's a centuries worth of examples there.

Ste

There's a centuries worth of examples *out* there

Not in that paper

Ok sorry here goes.

I do not really know much about Evolution science and I do not really like talking about it either as its usually a waste of time to do those Evo vs creation things.

So I do not know if to varites of the same species could not be able to breed or not if seperated over some tme, But I think they could as if there seperated (say varite A gets broken in to two places and forms group B & C and the fittist survive and pass on there jeans then only the jeans that suit that place will be in that type.
So say group B lives in a warm place then they will only have jeans suited for warm places after many years of breeding and group C are in a cold place then they will end up with jeans suited to cold places.

So if the two get back together they may not be able to mate as they no longer have compatible jeans.

But for Muslims this would mean that all you would have is two new variations of type A that are suited to that clmate or envirment but still the same as A even thoughing they can not breed with A or the other new varity.

If any thing this makes the variety worse of as it has bacome specalised for that enviroment meaning it has lost some of the genes it would have needed if the enviroment changes to how it was when both groups where one.

Meaning the varity could end up dying out because of this.

Sorry about how long I was with a replie I had to go and pray.

Adib

I'll check out the site at a later date as I'm still at work at the mo. I will try to print it off and read it over the week end.

Adib

Hi Adib,

"I do not really know much about Evolution science..."

So, your position on evolution and creation is a matter of faith? I'm puzzled, how can you try to criticise a scientific field when you, by your own admission, don't know much about it.


Anyway,

"...So if the two get back together they may not be able to mate as they no longer have compatible [genes]..."

And that is, by definition of what a species is, two new species coming from one. What you describe is called "allopatric speciation". Do a google with those search terms and you'll find out a lot.


Don't worry about long replies. Sometimes I go months without being able to get on h2g2.

Take care

Ste

"Well what I'm saying is that while different variations of the same species and type can occur, actual new species's can not."

Good definition--I can't think of an example offhand to disprove your claims, but at least you've given us a testable definition.

"Why does archeopterix having teeth prove its a dinosur. There is still two birds that have teeth today, or did one of them die out a couple of hundred years ago?"

It doesn't prove it's a dinosaur. However, it shows that it is possible for something to have neither all the traits of the dinosaurs it is suggested to evolve from nor all the traits of a modern bird, yet still exist.



"How did they know that archeopterix ould not fly well?"

Physiology and aerodynamics. Its bones are too heavy and don't have enough muscle attachments for it to fly efficiently with any normal amount of muscle. You couldn't build an efficient flying machine on that skeleton using the same sort of muscle systems that birds today have.

Unless Allah created birds in the past much differently, and with better muscles, than exist today, but killed them off long ago so that there are no written records of it.



"Plus its not one step is it, the dino's arms would have to start growing further up the body (Closer to the back than the front I mean), its fingers would have to enlongigate and there would have to be a sheath of skin attached to it all. Plus it would have to have a different type of wrist and bone structure to make even a fairly useless gliding wing."

Really? I'm not an expert, so I can't confirm this. Is there anyone here who knows enough about the subject to do so? It seems that moving the wings back would be the same as lengthening the neck--fairly easy to occur for other reasons. The fingers of dromasauride dinosaurs were already quite long--they were grappbing claws. The rist and bone structure could be produced by fusing bones--actually pretty useful in strengthening a claw in a predator.


"Also archeopterix had more fingers than these dino that evolved in to them."

Really? Source, please.


"Also what about strenth, it takes a lot of energy and stamina to keep a wing extended, try holding your arms out for 10 mins."

Plus the muscles to be able to glide would have to be arranged differently than that in the dino's arms and if it wanted to falp then these redundent arms it did not really use would suddenly have to increase in muscle capacity."

If it started leaping after incects, not a problem. Stamina would occur over many generations as those who could jump/fly farther were better hunters

"I read some where that there was actually a flying reptile as they call them, found that was older than archeopterix and was actually around before some of the dino's they said evolved in to archeopterix like animals."

If you mean a pterosaur of some sort--yes they are flying reptiles that existed before archeopterix and before most dinosaurs.

Flight evolved three times among vertibrates--pterosaurs, which used the whole hand as a wing; birds (archeopterix), which use the arm as a wing; and bats, wich use one finger as a wing.

The three groups are completely different, although all evolved from reptiles indirectly. Pterosaurs are Triassic in origen and related to, but not the same as dinosaurs. The two groups share a common ancestor, the thecodonts.

Birds evolved from dinosaurs in the late Jurrassic period. Pterosaurs did proceed the dinosaurs that birds evolved from, but pterosaurs aren't birds.

"I do not really know much about Evolution science and I do not really like talking about it either as its usually a waste of time to do those Evo vs creation things."

If you know so little about it, why are you so sure of the details of the evolution of birds?

Also, why did you come here to a thread on a subject you don't like to talk about and that you consider a waste of time? And why did you stay after making your origional point?



"But for Muslims this would mean that all you would have is two new variations of type A that are suited to that clmate or envirment but still the same as A even thoughing they can not breed with A or the other new varity."

I agree with Ste--you're defining a species with what you're calling a variety--a variety that can't breed with the unadapted members of origional group or with other varieties that adapted differently.

If your only definition of the difference between a species and a variety is that evolution doesn't make new species, but just new varieties and you allow varieties that fit the discription you have given us, then it seems that the conclusion is that all life on earth is just different varieties of the same species that can't interbreed.

It sounds likke all you've done then is to redefine the terminology.



BTW, thanks for coming here, Ste. Having an expert around is helpful.

Thats why I don't like talikng about it, all you get is critism.

I came here bcause its supposed to be about creation and not evolution. Where does it say evolution in the title?

As for the variation and species thing.

Cats are a species, tigers and leopards and domestic cats are all a variation of that species.

Dogs are a species and so german sheperds, and jack russels are all dogs but a different variation of dog.

Plus Ste about the article I read it and will talk about it later as I am busy to write a lenthy reply on that, but can I ask what the point of it was, as it does not seem like evolution to me.

An why don't you lay of me a little hmmmm, Unless you want to be talking on your own again. I sick of this, I always try to be poite and kind, and instread you all start having a go at me and basically call me dumb.

Maybe I came in here to learn more about evolution and creation, maybe I know a lot about birds because my mom bread birds, Maybe I don't like talking about evolution because you can't make a disbeliver belief in creation and you can't make a believer, believe in evolution as well.

Maybe I'm sick of being treated like dirt by lots of you simply because I don't now much about it yet I have faith in some thing you see as strange and puzzling.

Anyway I know not all of you are bad I'm just ranting at those who treat me like a moron you others are ok.

Adib

Adib,

I thought I was being perfectly polite, and I was making an effort to be polite. I am very sorry if you think otherwise, could you point me to the part which offended you? I like and respect you a great deal Adib, and if I were to chase you out of this thread because of rudeness I'd be quite upset.

Criticism is fine, it is part of any debate. But rudeness is not. Perhaps RDO could tone down his criticism a little.


"I came here bcause its supposed to be about creation and not evolution. Where does it say evolution in the title?"

This thread is attached to a entry entitled "Discrepancies in the Theory of Evolution - Part I" which is a part of the wider "Creation vs Evolution" university project.


"Cats are a species, tigers and leopards and domestic cats are all a variation of that species."

The term "species" is a word defined by biologists. When an animal can interbreed with another animal in nature then it is the same species. When it does not breed, it is different. Leopards, tigers, lions, domestic cats, cheetahs, etc., never breed with each other in nature, therefore they are different species. They are "reproductively isolated" from one another. Domestic dogs, however, *are* one species! (think chihuaha and irish wolfhound!), though they are not the same species as hyenas and wolves, etc.


"Plus Ste about the article I read it and will talk about it later as I am busy to write a lenthy reply on that, but can I ask what the point of it was, as it does not seem like evolution to me."

The flys that breed on the hawthorn fruit are never at the same developmental stage as their close relatives that breed on the apples. So, the two fly "varieties" are never at the stage *together* where they would court and breed together. This is also reproductive isolation, and therefore they are considered, by definition, two species. In this case we have actually witnessed evolution take place, as people introduced those apple trees in the 1860s! Cool, huh?

Evolution, when it comes down to it, is just the change of different forms of genes within a population over time. It doesn't take much for this (and hence evolution) to happen. Imagine you have a red and white flower from one species. There are 100 flowers, 50 of them are red, and 50 of them are white and the colour difference is because of two forms of one gene (an "allele"). In the next few generation of flowers this ratio changes (for whatever reason, natural selection, etc.) to 60:40. That is evolution, by definition ("the change in allele frequency over time"). You don't have to be an atheist to understand or believe in it. It's actually a little more complex than that, but the implications of evolution is where the difficult parts lay for some people; all related to a common ancestor, related closely to apes and other mammals, etc.


"Maybe I'm sick of being treated like dirt by lots of you simply because I don't now much about it yet I have faith in some thing you see as strange and puzzling."

I'm trying to teach you about evolution (I do it as a part of my PhD, so I enjoy this), why don't you tell us about your faith? I enquired last time whether your stance was a matter of faith and it was a sincere question. I respect people of faith (apart from idiotic fundamentalists of all creeds), and would love to know how their faith interacts with modern science - it's something I'll have to face in the future.

"Anyway I know not all of you are bad I'm just ranting at those who treat me like a moron you others are ok."

I hope you don't think I'm treating you like a moron, I was just trying to talk.

Take care,

Ste

Hey Ste was not talkingabout you, we go way back on these threads.

Its just that I always try to be tackfull, like on articles about Islam when some one says some thing who has not got much knowledge about Islam and say some thing wrong I never write some thing that will make them think Oh hes a nasty guy.

Sorry Just letting things get to me today, probabley because I went to this Christian site to get some Info and they had a vicious attack on Islam on there site, which has basically set the mood for my day.

Well you got me on the title thing, but it is ment to be discrepincys, I just want to share knowledge but not get in to a debate about creation and evolution.

Oh about the flies, I will try and bring it in to work tomorrow and write it up here. But I remember the figure of about 3 to 6 percent hybridisation rate or some think which means they can breed.

Adib

"Sorry Just letting things get to me today, probabley because I went to this Christian site to get some Info and they had a vicious attack on Islam on there site."

That'll be fundamentalism for you.


"I just want to share knowledge but not get in to a debate about creation and evolution."

Fair enough. But if you share some knowledge that someone else has a different opinion of, you're going to get a debate. Especially on h2g2. To any knowledge there are going to be different perspecitves on it. Yours comes from Islam, mine comes from biology. I am of the belief that religious and scientific knowledge are compatible. Both are truths, just of a different nature. I'm an atheist by the way, just to state my allegiences.


"Oh about the flies, I will try and bring it in to work tomorrow and write it up here. But I remember the figure of about 3 to 6 percent hybridisation rate or some think which means they can breed."

Excellent! I like your critical thinking. You'd make a good scientist. If you look at the graph on that website, you'll see the emergence times overlap a little, this is when that hybridisation is occuring. A hybrid is an organism (like a mule) that is from a mating of two species. Many species will breed with each other at a very low rate at the extremes of the population. 3-6% of the hawthorn flies mate with the apple species. 94-97% of them don't, and that is enough for speciation to happen and physical changes to occur. Hybrids are considered a by-product of speciation, and are usually not as fit (in the natural selection sense) as their parents, or even often totally sterile (see the mule). This means that there will still be a divide created and maintained between the two species.

As well as the time difference between the two, further proof of reproductive isolation lies within the physical differences I mentioned before. The flies are significantly different in size, they have different numbers of bristles on them (which is carefull genetically controlled) and most significantly the organ they use to lay their eggs within the fruit (called an "ovipositor") is much changed. Hawthorns are smaller than apples, and the apples species has already evolved a longer ovipositor. They are certainly different species, the result of the difference in emergence time has caused visible physical differences.

Ste

hi Muzaakboy,

Just wanted to say that although I'm not contributing to the thread at the moment I am following it and I find your postings very interesting and informative.

az

"I came here bcause its supposed to be about creation and not evolution. Where does it say evolution in the title?"

I agree with Ste's analysis.



"Cats are a species, tigers and leopards and domestic cats are all a variation of that species."

"Dogs are a species and so german sheperds, and jack russels are all dogs but a different variation of dog."

What about wolves? Are they the same species?

And since a domestic cat and a lion can't produce a viable offspring, how do you know that they're the same species, but a different specis from a domestic dog? Why not say all medium to large carnivorous land mammels are one species? Or all mammels?



"Maybe I came in here to learn more about evolution and creation, maybe I know a lot about birds because my mom bread birds, Maybe I don't like talking about evolution because you can't make a disbeliver belief in creation and you can't make a believer, believe in evolution as well."

You want to learn more about evolution without talking about it? Yet you respond when we talk about it. I'm pretty sure the latter part is false--I was under the impression that Alfred Wallace believed in Jehovah durring at least some of his life (possibly throughout it).



"Maybe I'm sick of being treated like dirt by lots of you simply because I don't now much about it yet I have faith in some thing you see as strange and puzzling."

I admit I was being a bit harsh. I'll try to be less so in the future.

Ok, I will type out what I thought of the article here. But please bear with me as ste has posted some info about them that was not actually on the site he gave me to look at.

What I came up with is that I do not think that they are a distinct species. This is because the two types of have many similarities as I know would be expected from a species developing from another.
According to the info I was given the two flies look the same in appearance and can breed with each other as shown by the 4 to 6% hybridization rate between them.
Also while the two types of fly use different fruit for reproduction they still both use fruit from the woody plants in the Rose taxonomic family.
Because the Hawthorn plant comes in over 50 different forms this suggested to me that the fruit of this plant varies in size which gave me the idea that one group of the Hawthorn flies got ‘attracted’ to the apples which as stated is the most widely grown fruit. For further clarification please see the end of this text where I say about the information that I think we need to have for better analysis.
Anyway to continue on a bit, what I think could possibly happen is this, the flies hatch out and they hibernate until the next season. When they come out of hibernation they work there way to the type of fruit they hatched out of and land it to and mate and lay there eggs. And this goes on as one big cycle.
The fact that there is a 4 –6% hybridization rate shows that the flies can some times get confused them selves on which fruit they should be mating on.
So here is a possible way that this new ‘species’ could come to happen.
In the area where these flies are, there could have been an abundance of Hawthorn flies or less hawthorn fruit than normal which meant a lot of them would have been able to breed. Instead of not breeding hey laid their eggs on the apples instead. Or a group of the flies could just have got it wrong and laid them on the apples instead who knows.

Now when these flies hatch out the ones on the hawthorn fruit will think, right I hatched out of a hawthorn and so that’s where I must breed. While the ones on the Apple tree hatch out think (metaphorically speaking) oh I hatched out on this I will lay my eggs on this.
So when mating time comes around they stay in their two different groups, and over time the gene pull is effectively lessened on the apple maggot fly side.
This is because the apples while effectively a safer place for there maggots are not more nutritious and so the only ones that will survive are the ones with the ability to survive on less nutrition than they used to have. Meaning that the things that make living on an apple easier would become more prominent while the other genes would disappear.
Meaning the apple maggot flies would end up being to specialized.

Because the two flies are not really mating with each other, the timetable of their breeding patterns starts to change.
Maybe this is because the apple provides less energy and is insufficient to them to use for a long hibernation. Though hibernation or what ever they do, uses low energy it still uses some energy and so maybe the apple ones started coming out earlier than the ones on the hawthorns because of this.
Then when the species started to hatch out at the right time for the apples they stayed in that balance of cycle for some reason. Maybe because it meant the flies maggots had a longer period of time they got enough energy to resume a full hibernation rather than the short one they where doing, plus any that did hatch before this time would die while there was no fruit to mate on.

Any way to continue, because there is a over lap of the two seasons this means there is a chance to mate with the two types, but they tend not to because they had either mated earlier or because they only want to mate on the type of fruit they hatched out on.
This is a survival thing as if they mate on the fruit type they hatched out on they know it can provide nutrition for the maggots, shelter from predators and also because if any thing should happen to the female after fertilization of the eggs it would not matter as they are laid in the fruit as soon as fertilization has happened.
Meaning there is less chance of her dying with out laying eggs after fertilization.
But the fact that there is a 4 to 6% hybridization rate shows that they do some times get it wrong and mate on the wrong fruit. For instance a male fly is doing his rounds and sees a sexy female on a apple, but his a hawthorn, But hey the fly has to have its way with those sexy legs and deep err black/blue eyes and puts there differences aside.

Ok very unrealistic I know but I think you get the point.

Some things that I think are needed to know are this:

Why did they start to change fruit in the first place?
Was there a shortage of hawthorns at that time?

Were there less hawthorns because man had destroyed them to plant the apple trees there instead?

How many eggs do they hatch on average?
This is because we have percentages giver but they mean nothing without knowing the number of eggs or maggots per type on average.

If the apples where not present in that area before could the flies have thought it was a bigger version of the hawthorn fruit?

Ok its all load of rubbish probably, I admit that, but its what I thought when I read the article.
There was another few points but can't remember what they were, as stupidly I though I would remember them and did not write them down.

I know Ste has said some things which clarrify some things but I did not have that info at the time I wrote this.

Adib