I think wolfboy was more asking about why the gallery is almost 2 gigabytes in size. And the answer is because tumblr artists don't know how to resize images without losing quality. They draw at a magnification of like 600 and then upload it at that resolution because they don't know how to scale it back to a normal screen size, or if they do they claim it looks worse or you can't see all their details. This causes a massive gain in file sizes that adds up very quickly.
@blakfayt, not only tumblr, whole internet. and no, they know how resize, but usually uploading HD versions too. and i tried uploading them if available.