In certain mammals, including hedgehogs and porcupines, the hairs are actually modified into difficult spines or quills. These are typically covered with thick plates of keratin and serve as safety versus predators. Jablonski[55] asserts head hair was evolutionarily useful for pre-humans to retain as it protected the scalp because they https://hairsaloninottawa97542.blogadvize.com/44346294/little-known-facts-about-hair-salon-in-ottawa