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.
Neanderthal
Neanderthals are known for their large cranial capacity, which at is larger on average than that of modern humans. One study has found that drainage of the dural venous sinuses (low pressure blood vessels that run between the meninges and skull leading down through the skull) in the occipital lobe region of Neanderthal brains appears more asymmetric than other hominid brains. In 2008, a group of scientists produced a study using three-dimensional computer-assisted reconstructions of Neanderthal infants based on fossils found in Russia and Syria. It indicated that Neanderthal and modern human brains were the same size at birth, but that by adulthood, the Neanderthal brain was larger than the modern human brain. They had almost the same degree of encephalisation (i.e. brain-to-body-size ratio) as modern humans.