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The tetrapods before Tiktaalik were also fishapods. The tetrapods after Tiktaalik were also fishapods. There are at least 14 named genera. Was is it not transitional?
That really isn't the issue. You said that there were no tetrapods before Tiktaalik.
I'm curious why it is considered a transitional between placental mammals and reptiles when in fact the eggs it lays are closer in structure to birds.
It bill is closer to a duck (I know I know it is not like a duck bill other than appearance)
it has a tail like a beaver so is it a representative of reptile to rodent, reptile to bird, reptile to mammal?
I didn't say that.
I thought that for a missing link to be a true missing link it had to be a an ancestor to the following fossil form.
I think that you are incorrect here. Tiktaalik was discovered and then later the fossilized footprints of true Tetrapods were discovered. There were true tetrapods not just fishapods before Tiktaalik.
it has a tail like a beaver so is it a representative of reptile to rodent, reptile to bird, reptile to mammal?
Why don't you show us these tetrapods. Links to pictures would be helpful.
From what I recall, all they have found are footprints which does nothing to help us determine if it is an early tetrapod with a lot of fish features.
Do you have a picture of the fossilized tetrapod referenced in your link?Their was some controversy but since then I do believe their is a consensus on this being actual tetrapods.
The creatures left the footprints as they tramped through mud in what was at the time an intertidal marine lagoon, south of the equator, along the south coast of the supercontinent called Laurasia.
Why might tetrapods have evolved to crawl onto land from the sea rather than from rivers or lakes? One hypothesis put forward by Niedźwiedzki is that the seashore provided a tempting new source of food: stranded fish, served up twice daily by the tides.
However, Ted Daeschler of the Academy of Natural Sciences in Philadelphia, Pennsylvania, warns that fossilised footprints can be misleading. "With all due respect to the scientists involved in this study, there may be other explanations for these suggestive tracks and traces," he says.
Clack, however, believes a reassessment of the consensus view on tetrapod evolution might be in order. "The evidence that these footprints were made by bona fide tetrapods is convincing," she says.
http://www.newscientist.com/article/dn18346-oldest-footprints-of-a-fourlegged-vertebrate-discovered.html#.UoueIOKBLZI
Here is a link for a blog that has a video too.
The Facts and Theories of Evolution: "Walking with Tetrapods"
It's tail is actually not like a beaver. They look similar at a distance, but upon closer inspection, they're quite different. Beaver tails are flatter, smaller, and they have these scales on them, and the beaver uses it for propulsion. The platypus uses it to in steering and that's it. As with a lot of things involving the playtpus, it kind of looks like something, but upon closer inspection...
And rodents ARE mammals, so 'reptile to rodent' and 'reptile to mammal' wouldn't even contradict each other.
I said tail like a beaver, which I might add is how it is sometimes described in some literature.
Do you have a picture of the fossilized tetrapod referenced in your link?
No I'm sorry I don't.
Perhaps then you would care to explain to us the role the Innuits played in Tiktaalik getting its name?
But it's tail isn't really 'like' a beaver, no more than, say, a whale's fin is 'like' a fish's fin. They have some similarities, but when you observe them closely you realize how different they are.
Their was some controversy but since then I do believe their is a consensus on this being actual tetrapods.
The creatures left the footprints as they tramped through mud in what was at the time an intertidal marine lagoon, south of the equator, along the south coast of the supercontinent called Laurasia.
Why might tetrapods have evolved to crawl onto land from the sea rather than from rivers or lakes? One hypothesis put forward by Niedźwiedzki is that the seashore provided a tempting new source of food: stranded fish, served up twice daily by the tides.
However, Ted Daeschler of the Academy of Natural Sciences in Philadelphia, Pennsylvania, warns that fossilised footprints can be misleading. "With all due respect to the scientists involved in this study, there may be other explanations for these suggestive tracks and traces," he says.
Clack, however, believes a reassessment of the consensus view on tetrapod evolution might be in order. "The evidence that these footprints were made by bona fide tetrapods is convincing," she says.
http://www.newscientist.com/article/dn18346-oldest-footprints-of-a-fourlegged-vertebrate-discovered.html#.UoueIOKBLZI
Here is a link for a blog that has a video too.
The Facts and Theories of Evolution: "Walking with Tetrapods"
Still, we are talking about 10 million years, a geologic eye-blink. All they have are footprints. We still don't have information on whether or not the species that left these tracks had internal gills or other fishapod features. Also, this does not put Tiktaalik's transitional features in doubt. What we have is a platypus of sorts. We have less derived features that stuck around in one of the sister taxa.
And still well within the Devonian era, no?
Still, we are talking about 10 million years, a geologic eye-blink. All they have are footprints. We still don't have information on whether or not the species that left these tracks had internal gills or other fishapod features. Also, this does not put Tiktaalik's transitional features in doubt. What we have is a platypus of sorts. We have less derived features that stuck around in one of the sister taxa.
And still well within the Devonian era, no?
So I ask you too, why do you think that Jenny Clack is so adamant about it being bona fide Tetrapods?
Why do you suppose Jenny Clack is so adamant about them being a bona fide
tetrapod? Do you think she is not equipped to make that determination?
I don't know. Why do you think?
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