Penis
Domestic cats have barbed penises, with about 120–150 one millimeter long backwards-pointing spines. Upon withdrawal of the penis, the spines rake the walls of the female's vagina, which is a trigger for ovulation. Lions also have barbed penises. Male felids urinate backwards by curving the tip of the glans penis backward. When male cheetahs urine-mark their territories, they stand one meter away from a tree or rock surface with the tail raised, pointing the penis either horizontally backward or 60° upward.
Lemur
A few lemurs have been noted to have relatively large brains. The extinct "Hadropithecus" was as large as a large male baboon and had a comparably sized brain, giving it the largest brain size relative to body size among all prosimians. The aye-aye also has a large brain-to-body ratio, which may indicate a higher level of intelligence. However, despite having a built-in tool in the form of its thin, elongated middle finger, which it uses to fish for insect grubs, the aye-aye has tested poorly in the use of extraneous tools.