Not to be rude or anything, but your mozilla SVG-images really stinks. They're several 100 kB big and two of them doesn't look very good either.
potrace -s -t 0 -a 0 -o output.svg input.pnm
I have no idea how you got the lizard heads so big, but it (the source) looks really messy. Haven't had the time to redo them yet.
For some reason your lizard heads have a gazillion tiny/invisible dots in different colors. After reworking your trex.svg I got it down to 5.6 kB from 557 kB. My own b/w mozilla head is even smaller, just 4.9 kB.
The gecko looks great, though!
I live without running water, since some clumsy plumber cut the wrong pipe, during the renovation going on in the house.