When it comes to fundraising marketing, conservation groups get donations by ignoring the boring species and focusing their campaigns on charismatic megafauna — like tigers, polar bears, and blue whales.
As Wikipedia notes, charismatic megafauna are “large animal species with widespread popular appeal that environmental activists use to achieve conservation goals well beyond just those species.”
This would explain why the WWF logo is a stylized giant panda–as opposed to, say, a caricature of the crocyniaceae lichenized fungus. But the concept of using cartoon characters to spur action isn’t unique to conservation non-profits and their flagship species.
Photo credit: Jeff Kubina on Flickr, via Creative Commons