Ticks hatch from eggs and develop through three active (and blood-feeding) stages: larvae (small-the size of sand grains); nymphs(medium-the size of poppy seeds); adults (large-the size of apple seeds). If you see them bigger, they’re probably partially-full or full of blood. They don’t jump, fly, or drop from trees onto your head and back. If you find one attached there, it most likely latched onto your foot or leg and crawled up over your entire body. Ticks are “programmed” to try and attach around your head or ears. On their normal hosts, (large mammalian hosts, deer, cattle, dog) ticks also usually crawl up; they want to blood feed around the head, neck, and ears of their host, where the skin is thinner and hosts have more trouble grooming.