Leopards are the most secretive and elusive of the large carnivores, and also the shrewdest. Pound for pound, they are better at climbing than other large cats and are capable of killing animals much larger than themselves. Coat color varies considerably among leopards, ranging from light buff or tawny shades in warmer, dryer regions to darker shades in densely forested areas. Leopards in eastern regions of Africa have circular spots or rosettes, while the markings of southern African leopards are square in shape. Leopards prefer to inhabit dense bush and rocky areas and river forests, but are highly adaptable, which is one reason they have adjusted so well to human encroachment. Leopards are primarily nocturnal, resting mostly in trees or thick bush during the daytime. Their spotted coat serves as a near-perfect camouflage.