Fish Footprints

[Muddy]

Oldest Land-Walker Tracks Found--Pushes Back Evolution (http://news.nationalgeographic.com/news/2010/01/100106-tetrapod-tracks-oldest-footprints-nature-evolution-walking-land.html)

[Strong]

I wonder what they tasted like, probably like frog's legs, I guess.

(A technical question: can you push evolution back any further? Surely it starts at the beginning by definition? Big bang to Britany Spears, one long sequence of inevitable events.)

[Atom]

(...)(A technical question: can you push evolution back any further? Surely it starts at the beginning by definition? Big bang to Britany Spears, one long sequence of inevitable events.)lol!

The evolution to which they refer is not that of life or matter, but of limb bearing fish.

[julien_simon]

Fish started walking when god decided.


I thought this thread was going to talk about carbon footprint of fish nowadays, being fished in giant cargo ships and shipped halfway around the globe.

nevermind...

[Brian]

PZ Myers wrote a blog (http://scienceblogs.com/pharyngula/2010/01/tetrapods_are_older_than_we_th.php) on it.


Excerpt:


What's it all mean? Well, there's the obvious implication that if you want to find earlier examples of the tetrapod transition, you should look in rocks that are about 400 million years old or older. However, it's a little more complicated than that, because the mix of existing fossils tells us that there were viable, long-lasting niches for a diversity of fish, fishapods, and tetrapods that temporally coexisted for a long period of time; the evolution of these animals was not about a constant linear churn, replacing the old model with the new model every year. Comparing them to cars, it's like there was a prolonged window of time in which horse-drawn buggies, Stanley Steamers, Model Ts, Studebakers, Ford Mustangs, and the Honda Civic were all being manufactured simultaneously and were all competitive with each other in specific markets…and that window lasted for 50 million years. Paleontologists are simply sampling bits and pieces of the model line-up and trying to sort out the relationships and timing of their origin.