Rabbit

How do you increase your hair density without poking more holes in your skin? In a way, you kill two birds with one stone by having more hairs come out of the holes that are already there. The holes are called "infundibulums," which are connected to the hair shaft. Normally, in humans and mice there is a single hair follicle coming out of an infundibulum. However, animals can increase their hair density by having more fibers growing out of a single infundibulum to increase hair density without having more holes, thus improving thermoregulation. In this immunostain, we show a hair follicle with three fibers coming out of the infundibulum.