Why Bird Penises Are So Weird

Опубликовано 25 октября 2017, 15:01

Male birds have the largest genital diversity of any class of animals because their sex chromosomes make it easy to pass male-helping mutations down the line.

LEARN MORE
**************
To learn more about this topic, start your googling with these keywords:
- Sex chromosome: A chromosome involved in determining the sex of an individual.
- Cloaca: A posterior orifice that serves as the only exit for the gastrointestinal, urinary and genital tracts.
- Mutation: An alteration in the DNA sequence that makes up a gene.
- Sexually-selected Trait: A trait based on a mutation that confers a reproductive advantage.
- BMP4: A protein whose presence halts the growth of bird penises in the egg.

If you liked this week’s video, you might also like:
An article from The Week about some of the strangest penises in the animal kingdom: theweek.com/articles/474417/12...

CREDITS
*********
Script Writer: David Goldenberg
Script Editor: Kate Yoshida
Video Illustrator: Ever Salazar
Video Director: Emily Elert
Video Narrator: Emily Elert
With Contributions From: Henry Reich, Alex Reich, Peter Reich
Music by: Nathaniel Schroeder

MinuteEarth is produced by Neptune Studios LLC
neptunestudios.info


SUPPORT MINUTEEARTH
**************************
If you like what we do, you can help us!:
- Become our patron: patreon.com/MinuteEarth
- Our merch: dftba.com/minuteearth
- Our book: minuteearth.com/books
- Share this video with your friends and family
- Leave us a comment (we read them!)

OUR LINKS
************
Youtube | youtube.com/MinuteEarth
TikTok | tiktok.com/@minuteearth
Twitter | twitter.com/MinuteEarth
Instagram | instagram.com/minute_earth
Facebook | facebook.com/Minuteearth
Website | minuteearth.com
Apple Podcasts| podcasts.apple.com/us/podcast/...

REFERENCES
**************
Brennan, P. and Prum, R. (2015). Mechanisms and Evidence of Genital Coevolution: The Roles of Natural Selection,Mate Choice, and Sexual Conflict. 1-21. Cold Spring Harbor Perspectives in Biology. Retrieved from: cshperspectives.cshlp.org/cont...

Brennan, P. (2013). Genital Evolution: Cock-a-Doodle-Don’t. Current Biology. R523-R525. Retrieved from: sciencedirect.com/science/arti...

Brennan, P., Birkhead, T., Zyskowski, K., van der Waagand, J., and Prum, R. (2008). Independent evolutionary reductions of the phallus in basal birds. Journal of Avian Biology, 39: 487-492. Retrieved from: onlinelibrary.wiley.com/doi/10...

Briskie, J. and Montgomerie, R. (1997). Sexual selection and the intromittent organ of birds. Journal of Avian Biology. 28: 73-86. Retrieved from: jstor.org/stable/3677097?seq=1...

Herrera, A., Brennan, P., and Cohn, M. (2014). Development of Avian External Genitalia: Interspecific Differences and Sexual Differentiation of the Male and Female Phallus. Sexual Development. 9: 43-52. Retrieved from: ncbi.nlm.nih.gov/pubmed/250115...

Reinhold, K. (1998). Sex linkage among genes controlling sexually selected traits. Sexual Selection. 44:1-7. Retrieved from: link.springer.com/article/10.1...

Image Credits:

Mandarin Ducks - Francis C. Franklin
commons.wikimedia.org/wiki/Fil...

Gorillas - Based on photo by Wikimedia user No escape
commons.wikimedia.org/wiki/Fil...

Lake Duck Penis - Kevin McCracken (Published in Nature 2001)