Many animals, both predators and prey, are very good at blending into the background to avoid being seen. The British paper, Mail Online, has a photo essay featuring the photography of Art Wolfe. The photos, taken over a period of 35 years, show how well animals can vanish into their environment. Below is just one example (can you see the owl?). See the 23-photo collection here. Try to see the animal before reading the photo caption. (H/t Syver More).