Hello i have had these spots for years now. They occur usually in warm weather. Last summer they were more spread out all over my body and my firends started calling me a dalmation (assholes). Right now i have it right over my belly button, on my side, on my shoulder and right under the bottom abs. Can anyone tell me what this is? Thanks

http://img108.imageshack.us/img108/9475/img2425ajq6.jpg
http://img98.imageshack.us/img98/5923/img2424atp3.jpg
http://img230.imageshack.us/img230/4717/img2423afd8.jpg