Does only GIF support animation?
Solution 1:
Taken from the Meta Topic on Post Formatting, an animated SVG file:
Image author: Pumbaa80 via Wikimedia
NOTE: This is not widely as accepted as GIF, so things like some versions of Internet Explorer will show the image by default but it will not be animated.
Solution 2:
There is a format of PNG out, APNG, that does what GIF does but better. It is still not supported in all browsers, but it is on the rise.
Edit:
Since the libpng(used by blink in chrome/opera/chromium) committee has locked up, and as it does not seem like any changes will come soon, a better choice might be to use Video with alpha-channel.
Shown here: Video transparency Example