MinuteEarth

Thanks to 23andMe for sponsoring this video! http://www.23andme.com/minuteearth

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.

Thanks also to our supporters on https://www.patreon.com/MinuteEarth
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To learn more, 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.
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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: http://theweek.com/articles/474417/12-weirdest-animal-penises-earth-updated
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Credits (and Twitter handles):
Script Writer: David Goldenberg (@dgoldenberg)
Script Editor: Kate Yoshida (@KateYoshida)
Video Illustrator: Ever Salazar (@eversalazar)
Video Director: Emily Elert (@eelert)
Video Narrator: Emily Elert (@eelert)
With Contributions From: Henry Reich, Alex Reich, Peter Reich
Music by: Nathaniel Schroeder: http://www.soundcloud.com/drschroeder


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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: http://cshperspectives.cshlp.org/content/7/7/a017749.abstract

Brennan, P. (2013). Genital Evolution: Cock-a-Doodle-Don’t. Current Biology. R523-R525. Retrieved from: http://www.sciencedirect.com/science/article/pii/S0960982213004430

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: http://onlinelibrary.wiley.com/doi/10.1111/j.0908-8857.2008.04610.x/abstract.

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

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: https://www.ncbi.nlm.nih.gov/pubmed/25011524.

Reinhold, K. (1998). Sex linkage among genes controlling sexually selected traits. Sexual Selection. 44:1-7. Retrieved from: https://link.springer.com/article/10.1007/s002650050508.

Image Credits:

Mandarin Ducks - Francis C. Franklin
https://commons.wikimedia.org/wiki/File:Pair_of_mandarin_ducks.jpg

Gorillas - Based on photo by Wikimedia user No escape
https://commons.wikimedia.org/wiki/File:Gorillafamily.JPG

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

Direct download: Why_Bird_Penises_Are_So_Weird.mp4
Category:general -- posted at: 11:50am EDT

The incredible chemical weapon-making abilities of fungi, bacteria, and plants have created an incredible array of compounds that are useful to humans.

Thanks to the University of Minnesota for sponsoring this video! http://twin-cities.umn.edu/

Thanks also to our supporters on https://www.patreon.com/MinuteEarth
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To learn more, start your googling with these keywords:
Bioprospecting: the systematic search for and development of new sources of chemical compounds, genes, micro-organisms, macro-organisms, and other valuable products from nature
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Subscribe to MinuteEarth on YouTube: http://goo.gl/EpIDGd
Support us on Patreon: https://goo.gl/ZVgLQZ
And visit our website: https://www.minuteearth.com/

Say hello on Facebook: http://goo.gl/FpAvo6
And Twitter: http://goo.gl/Y1aWVC

And download our videos on itunes: https://goo.gl/sfwS6n
___________________________________________

Credits (and Twitter handles):
Script Writer: Kate Yoshida (@KateYoshida)
Script Editor: Emily Elert (@eelert)
Video Illustrator: Jesse Agar
Video Director: Kate Yoshida (@KateYoshida)
Video Narrator: Kate Yoshida (@KateYoshida)
With Contributions From: Henry Reich, Alex Reich, Ever Salazar, Peter Reich, David Goldenberg
Music by: Nathaniel Schroeder: http://www.soundcloud.com/drschroeder


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References:

Bills, G.F. and Gloer, J.B. (2016) Biologically Active Secondary Metabolites from the Fungi. Microbiology Spectrum 4(6): 6

Cragg, G.M. and Newman, D.J. (2005) Biodiversity: A continuing source of novel drug leads. Pure and Appled Chemistry 77: 7–24

Mazid, M., Khan, T.A. and Mohammad, F. (2011) Role of secondary metabolites in defense mechanisms of plants. Biology and Medicine 3(2): 232–249.

Newman, D.J. and Cragg, G.M. (2016) Natural Products as Sources of New Drugs from 1981 to 2014. Journal of Natural Products 79: 629-661

O’Brien, J. and Wright, G.D. (2011) An ecological perspective of microbial secondary metabolism. Current Opinion in Biotechnology 22:552–558

Direct download: Where_Do_Our_Drugs_Come_From-.mp4
Category:general -- posted at: 11:21am EDT

Female hyenas don't have penises, but it sure looks like they do - and we still aren't quite sure why.

To start using Tab for a Cause, go to: http://tabforacause.org/r/minuteearth2

Thanks also to our supporters on https://www.patreon.com/MinuteEarth
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To learn more, start your googling with these keywords:
Pseudopenis: a structure that resembles a penis but is developmentally (and functionally) different
Masculinization: the process by which female genitalia is made to appear more like male genitalia
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If you liked this week’s video, you might also like:
Why It Sucks to Be a Male Hyena
https://www.youtube.com/watch?v=PBCNWmU5apE

Hyena having a baby at the Buffalo Zoo
https://www.youtube.com/watch?v=7rd7TvoPtWM
_________________________________________

Subscribe to MinuteEarth on YouTube: http://goo.gl/EpIDGd
Support us on Patreon: https://goo.gl/ZVgLQZ
And visit our website: https://www.minuteearth.com/

Say hello on Facebook: http://goo.gl/FpAvo6
And Twitter: http://goo.gl/Y1aWVC

And download our videos on itunes: https://goo.gl/sfwS6n
___________________________________________

Credits (and Twitter handles):
Script Writer: Kate Yoshida (@KateYoshida)
Script Editor: Alex Reich (@alexhreich)
Video Illustrator: Ever Salazar (@eversalazar)
Video Director: Kate Yoshida (@KateYoshida)
Video Narrator: Kate Yoshida (@KateYoshida)
With Contributions From: Henry Reich, Emily Elert, Peter Reich, David Goldenberg
Music by: Nathaniel Schroeder: http://www.soundcloud.com/drschroeder

Video Credits:
Spotted Hyenas Mating - Olivia Spagnuolo

Image Credits:
Female Spotted Hyena - Kate Yoshida
Spotted Hyena Pseudopenis - Kay Holekamp

Striped Hyena (Hyaena hyaena) - Flickr user Jean
https://www.flickr.com/photos/7326810@N08/3091611374

Brown Hyena (Parahyaena brunnea) - Bernard DUPONT
https://www.flickr.com/photos/berniedup/6472940707/

Proteles cristatus - Dominik Käuferle
https://commons.wikimedia.org/wiki/File:Proteles_cristatus1.jpg

Squirrel monkey - Wikimedia user Megapixie
https://commons.wikimedia.org/wiki/File:Squirrel_monkey-_fuji.jpg

Ring tailed lemur - Wikimedia user Sannse
https://commons.wikimedia.org/wiki/File:Ring_tailed_lemur_and_twins.jpg

Fossa - Ran Kirlian
https://commons.wikimedia.org/wiki/File:Cryptoprocta_Ferox.JPG

Binturong - Tassilo Rau
https://commons.wikimedia.org/wiki/File:Binturong_in_Overloon.jpg

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References:

Cunha GR, Risbridger G, Wang H, Place NJ, Grumbach M, Cunha TJ, Weldele M, Conley AJ, Barcellos D, Agarwal S, Bhargava A, Drea C, Hammond GL, Siiteri P, Coscia EM, McPhaul MJ, Baskin LS, Glickman SE. (2014) Development of the external genitalia: perspectives from the spotted hyena (Crocuta crocuta). Differentiation. 87(1-2):4-22. http://www.sciencedirect.com/science/article/pii/S030146811300087X?via%3Dihub

Frank LG (1997) Evolution of genital masculinization: why do female hyenas have such a large 'penis'? Trends Ecol. Evol. 12:58-62. http://www.cell.com/trends/ecology-evolution/abstract/S0169-5347(96)10063-X

Frank LG and Glickman SE (1994) Giving birth through a penile clitoris: parturition and dystocia in the spotted hyaena (Crocuta crocuta). J. Zool. 234:659–665. http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.1994.tb04871.x/abstract

Frank LG, Weldele ML, and Glickman SE (1995) Masculinization costs in hyaenas. Nature 377:584–585. http://www.nature.com/nature/journal/v377/n6550/abs/377584b0.html?foxtrotcallback=true

Glickman SE, Cunha GR, Drea CM, Conley AJ and Place NJ (2006) Mammalian sexual differentiation: lessons from the spotted hyena. rends in Endocrinology and Metabolism 17 (9): 349–356. http://www.sciencedirect.com/science/article/pii/S1043276006001767

Holekamp, KE, personal communication. August and September 2017.

Muller MN and Wrangham R (2002) Sexual Mimicry in Hyenas. The Quarterly Review of Biology 77 (1):3-16. http://www.journals.uchicago.edu/doi/abs/10.1086/339199?journalCode=qrb

Direct download: Why_Do_Female_Hyenas_Have_Pseudo-Penises-.mp4
Category:general -- posted at: 10:01am EDT

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