Steve_F

Thought that the following summary in Nature concerning long necked sea 'monsters' in the Triassic was very interesting.

http://www.nature.com/news/2004/0409...040920-12.html

Enjoy!

llDayo

I read about this just today, very interesting indeedy! I'm not an expert on dinosaurs or evolution but is it possible this could be an ancestor of snakes, given the way it catches its prey? It even had fangs!

MrDarwin

What I find interesting is that although this body plan seems to have evolved several times in the past, there seem to be no modern-day equivalents. There are many cases of convergence on similar body plans among unrelated groups, one of the most famous examples being that of sharks, ichthyosaurs, and dolphins.

Then again it's surprising that there were no giant whale-like reptiles in the Mesozoic or reptilian filter feeders of any kind--as far as we know, this kind of lifestyle has only evolved once, in the whale lineage (although the earliest whales were very similar to some of the Mesozoic marine reptiles).

Rhaedas

No, they are quite opposite the snake, with such a rigid neck. It's always been thought that given a long neck, they would strike as a snake does, but the article discusses the unlikelihood of that given the vertebrae structure.

Their speculation on the two possible uses for a long rigid neck are interesting. One, the length of the neck would mean a small increase along the throat equals a huge volume increase, thus the suction to capture prey. The other, in murky water the prey would only see a small head, and not the whole huge creature.

In thinking about it, the rigid vacuum cleaner approach would seem to work better, using simple liquid dynamics to aid the creature. While the more "glamorous" flexible neck that strikes the prey wouldn't work well underwater, due to water resistance impeding the movement.

So those who sucked more, did better.

Berthold

Although this is a branching from the original topic: Big filter feeders did evolve twice, among the cartilaginous fishes, who are an ancient branch of the vertebrates: manta rays and giant sharks.

Non-praying Mantis

What do you mean by this? Do you mean large, filter feeding animals? If so, then the whale shark and manta ray also fit this feeding method.

Filter feeding (not necessarily large animals) is an extremely common form of feeding with examples in practically every animal group!

NPM

RBH

According to this review, RBH

Plognark

Reminds me of the frog fish, although that little ugly bugger would seem to have evolved the suction feeding into an incredibly specialized and efficient mechanism.

Cool stuff

MrDarwin

Please re-read what I posted: you're overlooking the word "reptilian". There were numerous marine reptiles in the Mesozoic era from a number of different lineages that apparently took up the aquatic lifestyle independently, and they took on a wide variety of body shapes (e.g., plesiosaur, mosasaur, ichthyosaur) and occupied a number of ecological niches. None of them, as far as we know, became giant filter feeders like whales (or whale sharks). Why not?

Chuck Rightmire