Find out why most species of birds do not have a penis in this video abstract of new research published yesterday in Current Biology:

Source

Herrera AM, Shuster SG, Perriton CL, Cohn MJ. Developmental basis of phallus reduction during bird evolution. Current Biology Published online June 6, 2013. doi: 10.1016/j.cub.2013.04.062

Comments

  1. #1 Abraham Marangu
    kenya
    March 25, 2014

    I wish to get more on penis schrinking genes

  2. #2 Abraham Marangu
    kenya
    March 25, 2014

    i WISH TO KNOW MORE OF THE BIRDS SCHRINKING PENIS