This is incorrect.
You are not allowed to upload other people's photos in the
gallery.
However, embedding a photo from another site into a thread for discussion purposes like Jedd did, is perfectly fine - provided that you clearly identify and credit the source of the image.
In this case, the photo came from the ZSL website and I have edited Jedd's post to note that fact. It would have been better if I could identify a specific web page where the photo was on display - but from what I can tell, it was only used in one of the information carousels (yes, that's what web designers call them!) on the ZSL home page.
So the only thing Jedd didn't do correctly was crediting the source of the image - but that is easily fixed.
For future reference,
@littleRedPanda if there is a problem with a post - please report it rather than posting about it in a thread, because now there are two off topic posts about this in the thread because I had to reply to correct your post.