Expert: Walter Hintz - 10/5/2006

Question

-------------------------

Followup To

Question -

-------------------------

Followup To
The four chambered heart of mammals is more
complex that the two chambered heart of the fishes.

Is this at the organismal level? Is there any way you can give me another example.
For some reason I just dont get this...I feel dumb...I'm sorry.

Thanks for all your help.  

Answer
Don"t apologise  sharon.  These are tough questions.   Evolution of all organs shows increasing complexity.  We can also look at the excretory systems systems. Many nonvertebrates have structures called flame cells that function to get rid of excess nitrogen while ammmals have the more complex kidney.