Discovered: the missing link that solves a mystery of evolution

Originally posted by iori_komei
>>Is very glad he knows what obtuse means.

Obtuse, abstract, opaque, not fully clear.


Whats sad, is that most people my age would'nt know what obtuse, opaque or abstract even mean.


Ok, this post is so far off topic it's crazy.

Originally posted by iori_komei
Ok, this post is so far off topic it's crazy.

Ok, back on topic.

I think the whole "over-sized giant mudskipper with a crocodile head" thing is funny.

I think it's cute, I wish I could have one for a pet.


Anyways.

I get very happy when a gap in the evolutionary tree of life is filled.

after further consideration, and a peek at my year book, it seems that the item pictured is actually my junior year physic's teacher. the age seems about right, too.
sorry for the earlier confusion, all i had to do was get out my old school annuals and i coulda' answered this Q within the first post.
oh, well.
live and learn.


Boots out.

hey, loam,
would you please quit using words of more than one syabell. if you gotta use big words, like obtuse, to get your point acrosswould you be kind enough to use pictures for us dummies? it would be appreciated.


thanks,

Boots.



EDIT: it occured to me that whilst making fun of myself and other dumb people that i can't spell. go figure. just more grist for the dumb mill, i guess.


Boots out, again.

OK - I have a BSc in Biology and I have a problem with the evolutionary theory.

What bothers me about this whole "revelation" is that it is said that this is the link between the 'sea creatures' to that of the land creatures suggesting therefore that this is one of the first land creatures (Since evolution suggests the gradual transition of creatures from one form to another).
This huge carnivore therefore:

The evolved body allowed the fish to climb out of the shallow waters that lapped at tidal flats, estuaries and mud banks and spend time hunting for prey on land,

Source

My question is if this is one of the first land creatures what would he be hunting on land? With his size it would have to be a huge amount of little things or a small amount of very big creatures. Regardless if he was hunting something on land that would mean he is NOT the first land animal but there were a significant amount of other land animals before him.
I still do not buy the conventional evolutionary story. Undeniably evolution does play a role in speciation but I think it does so on a smaller scale.

Another issue I'd like to be explained is the evolution of instincts. Suckling for example is an instinct which is solely of mammals. What could have been the evolutionary mechanisms responsible for suckling? Is suckling evolutionary or designed?

My question is if this is one of the first land creatures what would he be hunting on land? With his size it would have to be a huge amount of little things or a small amount of very big creatures. Regardless if he was hunting something on land that would mean he is NOT the first land animal but there were a significant amount of other land animals before him.
I still do not buy the conventional evolutionary story. Undeniably evolution does play a role in speciation but I think it does so on a smaller scale.

Maybe he was hunting for larger species of insects or perhaps he hunted water creature from land. Altough I understand your point I'm sure there was something on land that was worth hunting. Plants and Insects should have been plentiful.

Another issue I'd like to be explained is the evolution of instincts. Suckling for example is an instinct which is solely of mammals. What could have been the evolutionary mechanisms responsible for suckling? Is suckling evolutionary or designed?

Okay.. The evolutionary mechanisms were probably: A starving baby with no capability of hunting or defending itself and a mother with milk driping out her tits

Well I don't have a BSc in biology but I thought that invertebrates had been using land for a while before vertebrates made the move. I know that horseshoe crabs have been using land for reproduction for several hundred million years.

I see numbers over 400 million years for true land-based inverts (e.g. Trigonotarbid arachnids)...

chelicerates

So it is A link between sea-to-land evolution - the link for vertebrates rather than inverts.


As for suckling, I would presume it evolved from a simple sebacious gland. Some (maybe all, not sure) monotremes produce milk-like secretions from glands thus basic suckling but no nipple. It's not hard to see the evolutionary advantage of such feeding mechanisms.

[edit on 7-4-2006 by melatonin]

ITS A STUPID FISH!!!!!!!!!!!!!!!!!!!!!!!!!!


missing link to what??????????? another fish?????????? OH come on...you people are stretching this a bit, .......uh-huh..................

Originally posted by cyraxx
ITS A STUPID FISH!!!!!!!!!!!!!!!!!!!!!!!!!!


missing link to what??????????? another fish?????????? OH come on...you people are stretching this a bit, .......uh-huh..................

It has been a bad week or so for literal creationists, what with the possible new hominid link and now a new water-land link. And it will continue...

The animal is a link between the fish and land vertebrates. You know those fishies that moved onto land around 375 million years ago that eventually evolved into all the terrestrial vertebrates we see today

ABE: and there is also a new paper in Science today that apparently uncovers the evolution of an 'irreducibly' complex biochemical system....

J. T. Bridgham, S. M. Carroll, J. W. Thornton, Science 312, 97 (2006).

[edit on 7-4-2006 by melatonin]

I thought this was the link between fish and tetrepods(SP?).

Meaning that this is the link between sea creturess and the things that started to explore land, but stayed primarily in the water.



Still, this has been a good week for evolution.

[edit on 4/7/2006 by iori_komei]

Originally posted by iori_komei
I thought this was the link between fish and tetrepods(SP?).

Meaning that this is the link between sea creturess and the things that started to explore land, but stayed primarily in the water.
[edit on 4/7/2006 by iori_komei]

Most definitely a good week.

Some terrestrials vertebrates were not true tetrapoda according to some modern cladistic classification schemes and are being defined as stem-tetrapods/digit-bearing vertebrates (e.g. Acanthostega). So terrestrial vertebrates includes these extinct semi-aquatics. Thus, it is a link between modern tetrapods, and also stem-tetrapods, so terrestrial vertebrates includes both....I think - haha, next time I'll just write tetrapod

For example, according to some this is not a true tetrapod...

Not a tetrapod?

Taxon Tetrapoda

terrestrial vertebrates

It's a cladistic minefield.


[edit on 7-4-2006 by melatonin]

looks like an ugly frog to me

might be wrong though

melatonin,
The invertibrates you linked me to were at the largest 7cm. Remember these where 4 to 9 feet long carniverous creatures and they needed a suitable diet in order to keep them alive. Therefore eating small insect does not seem suitable.

I do not see that this as any proof for an evolutionary trend that brought vertibrates into land.

Regarding suckling, you seem to miss out on the evolutionary mechanisms. THe need for sucking is obvious without which mammals could not have existed but what makes suckling an instinct. Evolution does not suggest that need creates a trait - evolution suggests that random mutations might have brought about traits that were prefereable for a species capacity to survive.

Suckling is a physical instinct that is unique to mammals but what is the evolutionary link for that trait (e.g. suckling fish, reptiles, birds?)

Originally posted by melatonin
Well I don't have a BSc in biology but I thought that invertebrates had been using land for a while before vertebrates made the move. I know that horseshoe crabs have been using land for reproduction for several hundred million years.

I see numbers over 400 million years for true land-based inverts (e.g. Trigonotarbid arachnids)...

chelicerates

So it is A link between sea-to-land evolution - the link for vertebrates rather than inverts.


As for suckling, I would presume it evolved from a simple sebacious gland. Some (maybe all, not sure) monotremes produce milk-like secretions from glands thus basic suckling but no nipple. It's not hard to see the evolutionary advantage of such feeding mechanisms.

[edit on 7-4-2006 by melatonin]

True, true. But since we are human not say. . .oh idont know, tyranids, its more important to us to find our missing links then theirs.

Go Chordates!!

Originally posted by JudahMaccabbi
melatonin,
The invertibrates you linked me to were at the largest 7cm. Remember these where 4 to 9 feet long carniverous creatures and they needed a suitable diet in order to keep them alive. Therefore eating small insect does not seem suitable.

I do not see that this as any proof for an evolutionary trend that brought vertibrates into land.

Well you need to rememeber that no-one is suggesting that tiktaalik spent it's life solely on land - it was able to move itself onto land. There are other advantages by doing this - escape from predators, as well as feeding. On the feeding issue you could see such stem-tetrapods holding a stationary position in shallow water and ambushing aquatic species and other stem-tetrapods. As juveniles small inverts would be a perfect diet. As adults, they probably would have spent much more time hunting aquatically - but the ability to move onto land would still be an advantage.

Regarding suckling, you seem to miss out on the evolutionary mechanisms. THe need for sucking is obvious without which mammals could not have existed but what makes suckling an instinct. Evolution does not suggest that need creates a trait - evolution suggests that random mutations might have brought about traits that were prefereable for a species capacity to survive.

Suckling is a physical instinct that is unique to mammals but what is the evolutionary link for that trait (e.g. suckling fish, reptiles, birds?)

The monotremes are seen as early mammals, they show an early form of suckling. They are seen as transitional between reptiles and mammals....

It is now well known that the Duckbill or Platypus (Ornithorhyncus) and the Spiny Anteater (Echidna) of Australia and Tasmania--with one representative of the latter in New Guinea, which seems to have been still connected--are semi-reptilian survivors of the first animals to suckle their young. Like the reptiles they lay tough-coated eggs and have a single outlet for the excreta, and they have a reptilian arrangement of the bones of the shoulder-girdle; like the mammals, they have a coat of hair and a four-chambered heart, and they suckle the young. Even in their mammalian features they are, as the careful research of Australian zoologists has shown, of a transitional type. They are warm-blooded, but their temperature is much lower than that of other mammals, and varies appreciably with the temperature of their surroundings.* Their apparatus for suckling the young is primitive. There are no teats, and the milk is forced by the mother through simple channels upon the breast, from which it is licked by the young. The Anteater develops her eggs in a pouch. They illustrate a very early stage in the development of a mammal from a reptile; and one is almost tempted to see in their timorous burrowing habits a reminiscence of the impotence of the early mammals after their premature appearance in the Triassic.

englishatheist.org...

Infant leaves egg, infant gains nutrition from specialised sebacious glands. There is no nipple, no true suckling - the milk just drips into the fur and infant takes up the nutritious liquid. It's not hard to see how this instinct developed as mammals evolved.

Going further back, it is possible that mammary glands evolved from a system specialised for keeping eggs clean and moist...

Mammary evolution - egg care

[edit on 8-4-2006 by melatonin]

Originally posted by JudahMaccabbi
My question is if this is one of the first land creatures what would he be hunting on land?

Its not as cut and dray as that, being a land creature or a river creature. Consider that these things would've been able to use their stronger 'finlegs' in the shallower waters, to support themselves and move along by sort of walking while in the water. Also, I would be careful in thinking of this particular species as the first one. There would've been a variety of animals, and only some would've gotten preserved, like this one.

Regardless if he was hunting something on land that would mean he is NOT the first land animal but there were a significant amount of other land animals before him.

Makes sense.

Is suckling evolutionary or designed?

How would we ever know if it was designed? Instincts would evolve like any other behaviour. THe most primitive mammals, like the platypus and echnidna, have milk glands, but no nipples, they just sort of ooze out milk from the glands. SO a young platypus would just lap it up. It doesn't seem to crazy to suggest that the nipple formed as a beneficial structure, to make the outflow of milk more efficient, and that the young that had a tendency to suck up the milk would be the ones that were the most fit.

I do not see that this as any proof for an evolutionary trend that brought vertibrates into land.

What would be good evidence for the evolution of tetrapods from some sort of fish? The greater development of the fins into something like legs. THere are already lots of fossils that show this, and this one shows it at an even earlier stage.

Originally posted by cyraxx
ITS A STUPID FISH!!!!!!!!!!!!!!!!!!!!!!!!!!

Precisely, its so fish like, that you almost can't call it a tetrapod, certainly not be looking it in quickly. But when you look at the structure of the limbs of these sorts of organisms, you can see that they are becoming more developed and stronger.

[edit on 10-4-2006 by Nygdan]

[edit on 10-4-2006 by Nygdan]

Good answer, Nygdan.

Judah, you remind me of a lot of people I know who majored in bio and don't accept evolution. Why? I mean, evolution is considered THE unifying theme of biology, so why would you major in bio? I never understood that.

I'd like to add that, as you hold a BS in biology, you know that behaviors are also subject to selection, according to evolutionary theory. Also, shared behaviors across relatively unrelated taxa are evidence of common descent. An example that comes to mind is scratching behavior in most birds.

If you look at them, most birds drop their wing when they scratch their shoulder. It's like, they stretch out their wing and scratch the shoulder with the leg on the same side of the body. It's funny, because this is an awkward way for them to scratch; they could more easily scratch their shoulder without stretching out their wing.

If you can't picture this yet, watch your cat or dog the next time its scratching its shoulder. You'll see it stretch its front leg out and scratch; that's the same thing most birds do. Funny, eh?

And, what do you think about homology? As a BS in bio, surely you are aware of homology as evidence for evolution. As for this fossil, I would hesitate to call it THE missing link; I'd rather call it a transitional fossil. Besides, this animal may be a mere evolutionary offshoot rather than an ancestor to land vertebrates. But, I think the important thing about this one is that it's a transitional form.

Since it does not exactly pertain to the subject of the thread I moved my discussion I to www.abovetopsecret.com...

[edit on 16/4/06 by JudahMaccabbi]