General Care Discussion :: Black on turtles shell

[StevenAkaProek]

I've got two 1 inch res and I've noticed some black on there shell in between these:
http://img239.imageshack.us/my.php?imag ... 216wr2.jpg
http://www.faunaclassifieds.com/photopo ... IM3477.JPG
(this is not my turtle just using as an example)
Is this okay? Is it from the heat? I've noticed they love to bask!

[megcornell]

I couldn't load the first picture, but if it's like the RES in the second picture, the black lines are from shell growth. You don't want the seams to be too large because that means the turtle is growing too fast which can lead to organ and shell issues.