Sources

http://evolution.berkeley.edu/evolibrary/home.php
http://library.thinkquest.org/20465/meiosis.html
http://media-2.web.britannica.com/eb-media/75/94975-036-651CE673.gif
http://evolution.berkeley.edu/evosite/evo101/images/geneflow_beetles.gif
http://misslorisbiohome.com/we/evolution/Images/Good%20picts/darwin_finches.jpg