The Monarch Butterfly

Lepidopterophobia is one of the unofficial names given to those afflicted with the fear of butterflies and moths.[1] 

A fear that perhaps has its origins in situations like the one on the left.

The Monarch Butterfly

Studying the Monarch genome has provided researchers with insights into migratory behavior, the circadian clock, juvenile hormone pathways and microRNAs that are differentially expressed between summer and migratory monarchs.[14][15][16]

The eastern North American Monarch butterfly population is notable for its multi-generational southward late summer/autumn migration from the United States and southern Canada to Mexico, covering thousands of miles.[3][4]

The Monarch undergoes complete metamorphosis consisting of four stages:



Laying eggs



Egg

The eggs are laid during the spring and summer months onto the leaves of milkweed plants.[5]



Caterpillar

The eggs hatch into caterpillars, which, after consuming their egg cases begin to feed on milkweed and sequester cardenolides, a type of *cardiac glycoside. (*Organic compounds containing a glycoside (sugar) that act on the contractile force of the cardiac muscle.)[17]



Chrysalis

In the chrysalis stage, the caterpillar spins a silk pad onto a horizontal substrate and hangs upside down.



Emerging from Chrysalis

The adult butterfly emerges after about two weeks, and hangs until its wings are dry. When conditions permit, it then flies to feed on a variety of nectar plants.

Female Monarchs have darker veins on their wings, and the males have a spot in the center of each hind wing.[6] Males are also slightly larger than female monarchs.

Male

Female

By ingesting a large amount of milkweed, monarch caterpillars are able to sequester the aforementioned cardenolides.[7]

After the caterpillar becomes a butterfly, the toxin shifts to different parts of the body. Since many birds attack the wings of the butterfly, having three times the cardenolides in the wings leaves predators with a very foul taste, and may prevent them from ever ingesting the body of the butterfly.[7] In order to combat predators that remove the wings only to ingest the abdomen, monarchs keep the most potent cardiac glycosides in their abdomens.[8]

Monarchs share the defense of noxious taste with the similar-appearing Viceroy butterfly in what is perhaps one of the most well-known examples of *Müllerian mimicry.[9]

*Müllerian mimicry, where two or more harmful species mutually advertise themselves as harmful.[18]

Monarch (left) and viceroy (right) butterflies exhibiting Müllerian mimicry [2]

The destruction of common milkweed has effectively eliminated the food source from most of the habitat monarchs used to use.[10]

Chip Taylor, director of Monarch Watch at the University of Kansas, said the Midwest milkweed habitat "is virtually gone" with 120–150 million acres lost.[11][12]

Mexican environmental authorities continue to monitor illegal logging of the Oyamel trees. The Oyamel is a major species of evergreen on which the overwintering butterflies spend a significant time during their winter diapause.[13]

Updates

In Photos: The Spectacular Migration of Monarch Butterflies / livescience.com / October 18, 2015

References & Resources


[1] http://phobias.about.com/od/phobiaslist/f/What-Is-The-Fear-Of-Butterflies-And-Moths.htm
[2] http://en.wikipedia.org/wiki/Monarch_butterfly
[3] Groth, Jacob (November 10, 2000). "Monarch Migration Study". Swallowtail Farms.
[4] "Monarch Migration". Monarch Joint Venture. 2013.
[5] "Monarch Butterfly Life Cycle and Migration". National Geographic Education. 2008-10-24.
[6] "Monarch, Danaus plexippus".
[7] Parsons, J.A. (1965). "A Digitallis-like Toxin in the Monarch Butterfly Danaus plexippus L". J. Physiol (178): 290–304.
[8] Glazier, Lincoln; Susan Glazier (1975). "Localization of Heart Poisons in the Monarch Butterfly". Science 188 (4183): 19–25. Bibcode:1975Sci...188...19B. doi:10.1126/science.188.4183.19. PMID 17760150.
[9] Ritland, D.; L. P. Brower (1991). "The viceroy butterfly is not a Batesian mimic". Nature 350 (6318): 497–498. doi:10.1038/350497a0. . "Viceroys are as unpalatable as monarchs, and significantly more unpalatable than queens from representative Florida populations."
[10] Bartel, Rebecca; Oberhauser, Karen; De Roode, Jacob; Atizer, Sonya (February 2011). "Monarch butterfly migration and parasite trasmission in eastern North America". Ecology 92 (2)
[11] Brennen, Shannon. "For Love of Nature: Annual monarch butterfly migration in peril". The News & Advance, Lynchburg, Virginia.
[12] Wines, Michael, Monarch Migration Plunges to Lowest Level in Decades March 13, 2013 NYT
[13] John E. Losey, Linda S. Rayor & Maureen E. Carter (1999). "Transgenic pollen harms monarch larvae" (PDF). Nature 399 (6713): 214. doi:10.1038/20338. PMID 10353241.
[14] "Project Milkweed".
[15] Zhan S, Merlin C, Boore JL, Reppert SM (November 2011). "The Monarch Butterfly Genome Yields Insights into Long-Distance Migration". Cell 147 (5): 1171–85. doi:10.1016/j.cell.2011.09.052. PMC 3225893. PMID 22118469.
[16] Stensmyr MC, Hansson BS (November 2011). "A Genome Befitting a Monarch". Cell 147 (5): 970–2. doi:10.1016/j.cell.2011.11.009. PMID 22118454.
[17] http://en.wikipedia.org/wiki/Cardiac_glycoside
[18] http://en.wikipedia.org/wiki/Mimicry



Image Credits

"Monarch Butterfly Danaus plexippus Laying Eggs" by Photo by and (c)2009 Derek Ramsey (Ram-Man) - Self-photographed. Licensed under GNU Free Documentation License 1.2 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_Butterfly_Danaus_plexippus_Laying_Eggs.jpg#mediaviewer/File:Monarch_Butterfly_Danaus_plexippus_Laying_Eggs.jpg


"Danaus plexippus, Monarch egg" by Bfpage - Own work. Licensed under Creative Commons Attribution-Share Alike 4.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Danaus_plexippus,_Monarch_egg.jpg#mediaviewer/File:Danaus_plexippus,_Monarch_egg.jpg

"Monarch Butterfly Danaus plexippus Feeding Down 3008px" by Photo (c)2007 Derek Ramsey (Ram-Man) - Own work (Own Picture). Licensed under GNU Free Documentation License 1.2 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_Butterfly_Danaus_plexippus_Feeding_Down_3008px.jpg#mediaviewer/File:Monarch_Butterfly_Danaus_plexippus_Feeding_Down_3008px.jpg

"Monarch Butterfly Cocoon 3" by Greyson Orlando - Own work. Licensed under Creative Commons Attribution 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_Butterfly_Cocoon_3.jpg#mediaviewer/File:Monarch_Butterfly_Cocoon_3.jpg

"Eclosing Danaus plexippus, monarch butterfly, life cycle Megan McCarty118" by Bfpage - Own work. Licensed under Creative Commons Zero, Public Domain Dedication via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Eclosing_Danaus_plexippus,_monarch_butterfly,_life_cycle_Megan_McCarty118.JPG#mediaviewer/File:Eclosing_Danaus_plexippus,_monarch_butterfly,_life_cycle_Megan_McCarty118.JPG

"Monarch In May" by Kenneth Dwain Harrelson - Taken by Kenneth Dwain Harrelson. Licensed under Creative Commons Attribution-Share Alike 3.0-2.5-2.0-1.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_In_May.jpg#mediaviewer/File:Monarch_In_May.jpg

"Monarch Butterfly Danaus plexippus Male 2664px" by Photo by and (c)2007 Derek Ramsey (Ram-Man) - Own work (Own Picture). Licensed under GNU Free Documentation License 1.2 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_Butterfly_Danaus_plexippus_Male_2664px.jpg#mediaviewer/File:Monarch_Butterfly_Danaus_plexippus_Male_2664px.jpg

"Monarch Viceroy Mimicry Comparison" by PiccoloNamek (2005-08-22, uploaded by User:Lokal_Profil on 13:50, June 15, 2006) and Derek Ramsey (User:Ram-Man). - Image:Viceroy Butterfly.jpg and Image:Monarch Butterfly Danaus plexippus Purple Coneflower 3008.jpg. Licensed under GNU Free Documentation License 1.2 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Monarch_Viceroy_Mimicry_Comparison.jpg#mediaviewer/File:Monarch_Viceroy_Mimicry_Comparison.jpg