Did amphibians evolve in the sea? Really?

rwjefferson · December 13, 2013

did amphibians evolve in the sea.iii

Science authority [/dogma] currently states that the earliest amphibians evolved in the Devonian Period with multi-jointed leg-like fins with digits that enabled them to crawl along the sea bottom.

Really?

Which amphibians still lay their eggs in the sea?

Where are the most primitive amphibians currently found?

Where are the largest amphibians currently found?

Can you offer reason to believe what Authority tells you so?

Did amphibians evolve in currents and fresh water?

peace

ron

Moontanman · December 13, 2013

did amphibians evolve in the sea.iii

Science authority [/dogma] currently states that the earliest amphibians evolved in the Devonian Period with multi-jointed leg-like fins with digits that enabled them to crawl along the sea bottom.

Really?

Which amphibians still lay their eggs in the sea?

Where are the most primitive amphibians currently found?

Where are the largest amphibians currently found?

Can you offer reason to believe what Authority tells you so?

Did amphibians evolve in currents and fresh water?

peace

ron

While i tend to agree that amphibians probably evolved in freshwater others do disagree but just because no current amphibians live in salt water doesn't mean none ever did or that they didn't originate there.

There are modern amphibians that lay their eggs on land and modern reptiles that give birth to live young, it not always a good idea to extrapolate backwards into time to make assumptions...

Ringer · December 13, 2013

True amphibians didn't evolve until the carboniferous period, if you don't count labirynthodonts as true amphibians. Ichthyostega evolved in swamps which are freshwater, since they seem to represent the closest common relative between fishes and amphibians it can be assumed that amphibians probably developed in freshwater. the sarcopterygii that navigated the sea bottom with their fins were not amphibious. I don't know what 'authority' told you these were amphibians.

Delta1212 · December 13, 2013

If cetaceans evolved from land dwelling mammals, where are the land whales?

Moontanman · December 13, 2013

If cetaceans evolved from land dwelling mammals, where are the land whales?

The land whales are extinct but ask and ye shall receive...

http://en.wikipedia.org/wiki/Evolution_of_cetaceans

The traditional theory of cetacean evolution was that whales were related to the mesonychids, an extinct order of carnivorous ungulates (hoofed animals), which resembled wolves with hooves and were a sister group of artiodactyls (even-toed ungulates). These animals had unusual triangular teeth similar to those of whales. This is why scientists long believed that whales evolved from a form of mesonychid. But more recent molecular phylogeny data suggest that whales are more closely related to the artiodactyls, specifically the hippopotamus.^[2] The strong evidence for a cladecombining cetaceans and artiodactyls is further discussed in the article Cetartiodactyla. However, theanthracothere ancestors of hippos do not appear in the fossil record until millions of years afterPakicetus, the first known whale ancestor.

The molecular data is supported by the recent discovery of Pakicetus, the earliest proto-whale (see below). The skeletons of Pakicetus show that whales did not derive directly from mesonychids. Instead, they are artiodactyls that began to take to the water soon after artiodactyls split from mesonychids. Proto-whales retained aspects of their mesonychid ancestry (such as the triangular teeth) which modern artiodactyls have lost. An interesting implication is that the earliest ancestors of all hoofed mammals were probably at least partly carnivorous or scavengers, and today's artiodactyls and perissodactyls became herbivores later in their evolution. By contrast, whales retained their carnivorous diet, because prey was more available and they needed higher caloric content in order to live as marine endotherms. Mesonychids also became specialized carnivores, but this was likely a disadvantage because large prey was not yet common. This is why they were out-competed by better-adapted animals like thecreodonts and later Carnivora which filled the gaps left by the dinosaurs.

Edited December 13, 2013 by Moontanman

Delta1212 · December 13, 2013

The land whales are extinct but ask and ye shall receive...

http://en.wikipedia.org/wiki/Evolution_of_cetaceans

That was sort of my point, but it was still an interesting read. Thank you.

rwjefferson · December 15, 2013

kind and well reasoned responses are all ways welcome

today.iii

What are the most primitive tetrapods found today?

What are the largest tetrapods found today?

in other words

Where are the largest and most primitive tetrapods currently found?

Are fossils more likely to be found in the extinction of a flowing stream or some old dried up pool?

Can you prove whales did not first evolve 0nce upon a time between land and sea and wind?

def: trick question

Does a spinning stone skip over the water because lower pressure sometimes hoovers up?

@least by me

rw~

Moontanman · December 15, 2013

kind and well reasoned responses are all ways welcome

today.iii

What are the most primitive tetrapods found today?

What are the largest tetrapods found today?

I'm not sure what you mean here the idea that any current life forms are primitive is misleading at best, but if you mean the most basal then probably the large gilled salamanders like mudpuppies or hellbenders come closest to what you are looking for.

in other words

Where are the largest and most primitive tetrapods currently found?

See above:

Are fossils more likely to be found in the extinction of a flowing stream or some old dried up pool?

I would say it depends on what fossils you are asking about but fossil sea creatures like trilobites and mollusks are my bet.

Can you prove whales did not first evolve 0nce upon a time between land and sea and wind?

Yes see post #5 in this thread.

def: trick question

Does a spinning stone skip over the water because lower pressure sometimes hoovers up?

@least by me

rw~

This is off topic, but I once got a stone to skip 37 times... and they skip by bouncing off the surface of the water...

Ringer · December 15, 2013

I'm not sure what you mean here the idea that any current life forms are primitive is misleading at best

In common language I agree completely. But in reference to character states primitive just means less derived from an ancestral state.

Moontanman · December 15, 2013

In common language I agree completely. But in reference to character states primitive just means less derived from an ancestral state.

Then the large salamanders would be my answer...

overtone · December 16, 2013

did amphibians evolve in the sea.iii

Science authority [/dogma] currently states that the earliest amphibians evolved in the Devonian Period with multi-jointed leg-like fins with digits that enabled them to crawl along the sea bottom.

Nothing in current scientific understanding prevents you from assuming that the sea bottom crawlers wandered up into rivers and their communicant lakes; in these shallower, changeable, wave-sheltered, predator poor, and food rich littoral environs finding legs and crawlling even more useful than in or along the salt ocean.

If that seems more likely to you, no "dogma" forbids.

rwjefferson · December 17, 2013

yes

0 yes indeed allison wonderland.iii

Once upon long times ago we and whales evolved from lobed finned fish crawling up and against the flow and the largest tetrapods are currently balaenoptera musculi and fossils are more likely to be found in swamps than flowing streams. When were cryptic branchuses invented and popularized? Is exposing gills a juvenile trait?

Look what is written in space and earth and flesh and do not be afraid of finding and sharing your best answers. Where are the goliaths of giant salamanders currently found? Are flattened body and muscular clawed feet good for crawling against stream and tide and over land? How about fluffy gills?

ItS

peace

ron

caveat emptor

In my next thread I intend to ask the otherwise intelligent engineers of Oracle's America's Cup sailboat team and David Pogue how hydro-foils them into thinking a wing under water is sucked up differently than a spinning stone.

Moontanman · December 17, 2013

yes

0 yes indeed allison wonderland.iii

Once upon long times ago we and whales evolved from lobed finned fish crawling up and against the flow and the largest tetrapods are currently balaenoptera musculi and fossils are more likely to be found in swamps than flowing streams. When were cryptic branchuses invented and popularized? Is exposing gills a juvenile trait?

Look what is written in space and earth and flesh and do not be afraid of finding and sharing your best answers. Where are the goliaths of giant salamanders currently found? Are flattened body and muscular clawed feet good for crawling against stream and tide and over land? How about fluffy gills?

ItS

peace

ron

caveat emptor

In my next thread I intend to ask the otherwise intelligent engineers of Oracle's America's Cup sailboat team and David Pogue how hydro-foils them into thinking a wing under water is sucked up differently than a spinning stone.

http://en.wikipedia.org/wiki/Giant_salamander

Neither whales or humans evolved directly from fish, and a skipping stone stops skipping if it goes under water..

Ringer · December 17, 2013

When were cryptic branchuses invented and popularized?

The son of Apollo?

Is exposing gills a juvenile trait?

It depends on what species you're looking at, and what you mean by exposed gills. There's a difference between exposed gills that don't have an operculum and external gills.

Are flattened body and muscular clawed feet good for crawling against stream and tide and over land? How about fluffy gills?

Flattened body can be used for a variety of different things, from streamlining to increasing surface area exposed to the sun. Clawed feet can be helpful in streams and tides if the floor of the waterbed are solid enough, but they definitely help on land.

I'll assume you mean external gills. These are pretty helpful because O2 can be readily gained in a passive manner.

Moontanman · December 17, 2013

On the large salamander issue, when Europeans first came to the Ohio river valley a bad forest fire burned off evidently many square miles some place in what is now southern Ohio and the watershed of a medium sized stream was burned and after many dozens of huge "antlered lizards" were found dead in the stream bed, reports say they were more than 12 feet long. While not falsifiable by any means the description sounded more like huge mudpuppies with the antlers being the external gills which is by the way a neotenous trait... Completely apocryphal by the way as no specimens were kept...

I would like to say that mudpuppies are a case of neoteny, tiger salamander larvae are almost indistinguishable from mudpuppies and rather large but the giant salamanders breath mostly through their skin, I know it sounds funny but some turtles breath through their anus so it's not as odd as it sounds...

Ophiolite · December 18, 2013

@ rwjefferson, help me out here please. What is the object of your posts? I don't know whether you just have a quaint way of asking questions, or whether you are implicitly challenging science, or the scientific method. I don't know if you are seeking to educate, or be educated; whether you want a debate, or an argument. Would you clarify please?

rwjefferson · December 20, 2013

@ rwjefferson, help me out here please. What is the object of your posts? I don't know whether you just have a quaint way of asking questions, or whether you are implicitly challenging science, or the scientific method. I don't know if you are seeking to educate, or be educated; whether you want a debate, or an argument. Would you clarify please?

clueless.iii

My object is to challenge the hounds of dogma that offer insult and ban instead of kind and well reasoned answers. What is yours? How long have you been lurking?

Have your heard tails of tetrapods like Andreas.davidianii growing six feet or more?

Why do tetrapods slither and crawl upstream to spawn?

kind and well reasoned answers are always greatly appreciated

@least by me

ron

btw

gills shown by axolotls are neotenic

if you know what I mean

_____________________________

ode to bullwinkle and other furry tetrapods.iii

Thanks for the image of young Andrias and the other grinning child of the extended Cryptobranchidae family.

Is crawling upstream conducive for flattened body and muscular pods? How about navigating around a swamp? Do you believe everything authority tells you so?

ItS

peace

ron

I do not believe curvature is force 0r gravity is not

Moontanman · December 20, 2013

clueless.iii

My object is to challenge the hounds of dogma that offer insult and ban instead of kind and well reasoned answers. What is yours? How long have you been lurking?

You have been getting kind and well reasoned answers

Have your heard tails of tetrapods like Andreas.davidianii growing six feet or more?

What is that?

Why do tetrapods slither and crawl upstream to spawn?

I don't know that they do but hellbenders do crawl around on the bottom of swift mountain streams...

btw

gills shown by axolotls are neotenic

if you know what I mean

I am aware of axolotls, but no one has mentioned them but you...

_____________________________

ode to bullwinkle and other furry tetrapods.iii

Thanks for the image of young Andrias and the other grinning child of the extended Cryptobranchidae family.

You're welcome...

Is crawling upstream conducive for flattened body and muscular pods?

It works for hellbenders

How about navigating around a swamp?

It works for alligators... and mudpuppies...

Do you believe everything authority tells you so?

I don't but I don't see your point either..

rwjefferson · December 23, 2013

thanks again.iii

and I wait patiently for your next most kind and well reasoned answers

Why do salamanders of enormous size like Andrias tend to crawl and spawn upstream in fertile mountain pools?

Does crawling up under mountain streams select for flattened head and muscular limbs balanced between nose and tail?

How about swamps?

still crawling against the stream

ron

ItS

peace

Moontanman · December 23, 2013

thanks again.iii

and I wait patiently for your next most kind and well reasoned answers

Why do salamanders of enormous size like Andrias tend to crawl and spawn upstream in fertile mountain pools?

Does crawling up under mountain streams select for flattened head and muscular limbs balanced between nose and tail?

How about swamps?

still crawling against the stream

ron

ItS

peace

I'm not sure those salamanders do crawl upstream, the only really large salamanders I am familiar with are hell benders and they spawn in the streams where they live. If the description in wiki is accurate that would seem to be the case with the giant Asiatic salamanders as well.

Living on the bottom in fast flowing streams I am sure does influence the shape of the animals that live there. A flattened shape and muscular body would seem to be necessary but they also spend considerable amounts of time under large rocks to shield themselves from the current as well..

Swamp dwelling mudpuppies do have to contend with currents, yes swamps do have areas of high currents, at least where I live and that is where the swamp dwelling mudpuppies live as well. In fact those swamp dwelling mudpuppies are only found in areas of tidal flux...

I'm not sure what you are getting at here, you seem to be fishing for something, what is it you want to know? I happen to be well acquainted with the aquatic salamanders of the south eastern US, I await your next question...

rwjefferson · January 3, 2014

ode to intelligent tetrapods and bullwinkle

wanting and saying does not make it so and reason in kind without self evident observation is not reason enough

and thanks for the arthropods and fish

current wiki.101

Specifically salamanders of unusual size like Andreas and Desmognathus still seek fertile mossy mountain seeps and springs and strong limbs and toes are also good for crawling out of and onto and up and overland.

def: swamp

a wetland often partially or intermittently covered with water; especially one dominated by reeds and roots and woody vegetation

So yes indeed allison wonderland

0nce upon a dream time ago primitive dolphins crawled up and out of ancient mossy mountain seeps and pools and streams and torrents ripe with bite size arthropods and fish long before they crawled out of reedy rooty woody wetlands and walked back into the salty sea. Look 0nce more closely and you just might find traces and fossils of ancient tetrapod bones ground and buried with the rocky bones of the mountains that grew hundreds of millions of years ago.

big history project~

"To escape the carnage of the sea, some creatures crawl out onto land as well. At first they are forced to return to the salty seas to reproduce, but then they discover a way to bring a bit of the ocean with them; the egg."

Respond as you must and I will try not to cringe as otherwise intelligent tetrapods propagate dogma that authority tells them so.

ron

a stone pushes down on water and water pushes back and up

a cheetah pushes down on ground and ground pushes back and up

a cheetah skips over land like stones skip over water

Moontanman · January 3, 2014

ode to intelligent tetrapods and bullwinkle

wanting and saying does not make it so and reason in kind without self evident observation is not reason enough

and thanks for the arthropods and fish

current wiki.101

Specifically salamanders of unusual size like Andreas and Desmognathus still seek fertile mossy mountain seeps and springs and strong limbs and toes are also good for crawling out of and onto and up and overland.

def: swamp

a wetland often partially or intermittently covered with water; especially one dominated by reeds and roots and woody vegetation

So yes indeed allison wonderland

0nce upon a dream time ago primitive dolphins crawled up and out of ancient mossy mountain seeps and pools and streams and torrents ripe with bite size arthropods and fish long before they crawled out of reedy rooty woody wetlands and walked back into the salty sea. Look 0nce more closely and you just might find traces and fossils of ancient tetrapod bones ground and buried with the rocky bones of the mountains that grew hundreds of millions of years ago.

big history project~

"To escape the carnage of the sea, some creatures crawl out onto land as well. At first they are forced to return to the salty seas to reproduce, but then they discover a way to bring a bit of the ocean with them; the egg."

Respond as you must and I will try not to cringe as otherwise intelligent tetrapods propagate dogma that authority tells them so.

ron

a stone pushes down on water and water pushes back and up

a cheetah pushes down on ground and ground pushes back and up

a cheetah skips over land like stones skip over water

So in reality none of this really meant anything but a away to get a rise out of people by building strawmen you could really easily kick down... good job that...

rwjefferson · January 8, 2014