For the Sake of Science

Thought of the day

7 Responses

1. 

   Nate, on July 22, 2010 at 9:45 pm said:

   Depends on how you define mammal really, there were mammal like reptiles almost 300 MYA.

   If you mean modernish mammals, placental mammals, than your about right.
2. 

   NewEnglandBob, on July 22, 2010 at 10:11 pm said:

   The mammalian line of descent diverged from an amniote line at the end of the Carboniferous period (300 MYA). One line of amniotes would lead to reptiles during the Triassic (250-200 MYA), while the other would lead to synapsids. According to cladistics, mammals are a sub-group of synapsids.
3. 

   Nate, on July 22, 2010 at 10:58 pm said:

   I’ve always been interested in these splits and “when” they happened. Its a shame that the passage of time degrades and destroys the available evidence, which forces us to talk in increments of millions of years.

   A little too far back in time for what I studied in school but still very captivating.
4. 

   Kel, on July 23, 2010 at 7:11 am said:

   They may have came on the scene some 200 million years ago, but it wasn’t until 65 million years ago that they became a big player…
5. 

   Nate, on July 23, 2010 at 8:59 am said:

   A big player in the sense that the dinosaurs appear to have died out around that time so mammals could step into a giant pair of shoes. But than again they may have played a larger role than we know, its all just educated guess work, we think the fossil record is pretty good right now, but it really is still a mess of holes :( :( :(

   I remember hearing about some dinosaurs POSSIBLY surviving the K-T event by a million years or so. Anyone else read or hear anything about this possibility? I realize its not that crazy to think that the dinosaurs didn’t all die out at one time and a lucky few species may have survived a great deal longer.
6. 

   Michael Hawkins, on July 23, 2010 at 4:47 pm said:

   That doesn’t sound familiar, but if you want to get technical, dinosaurs still exist in the form of what we call birds.
7. 

   Nate, on July 23, 2010 at 7:03 pm said:

   Sorry I did actually mean non-avian dinosaurs.

   http://scienceblogs.com/evolvingthoughts/2007/06/did_some_dinosaurs_survive_the.php

   Its not exactly what I was looking for but it would be a bombshell if we were to find more dino’s above the K-T line.

   Of course there are a lot of dinos above it in reality but conventional wisdom would suggest they were “washed out” unless they routinely appeared above.