Monarch butterfly
Dec. 29th, 2013 10:21 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
lauerzhttp://en.wikipedia.org/wiki/Monarch_butterfly
http://www.monarch-butterfly.com/monarch-migration.html
http://nationalzoo.si.edu/animals/invertebrates/news/monarchmigration.cfm
http://video.nationalgeographic.com/video/animals/bugs-animals/butterflies-moths/butterfly_monarch/
http://www.fs.fed.us/wildflowers/pollinators/monarchbutterfly/migration/
http://www.monarchwatch.org/
http://dsc.discovery.com/tv-shows/life/videos/monarch-butterfly-winter-migration.htm
http://www.nytimes.com/2013/11/24/sunday-review/the-year-the-monarch-didnt-appear.html?_r=0
http://www.monarch-butterfly.com/monarch-migration.html
http://nationalzoo.si.edu/animals/invertebrates/news/monarchmigration.cfm
http://video.nationalgeographic.com/video/animals/bugs-animals/butterflies-moths/butterfly_monarch/
http://www.fs.fed.us/wildflowers/pollinators/monarchbutterfly/migration/
http://www.monarchwatch.org/
http://dsc.discovery.com/tv-shows/life/videos/monarch-butterfly-winter-migration.htm
http://www.nytimes.com/2013/11/24/sunday-review/the-year-the-monarch-didnt-appear.html?_r=0
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Date: 2013-12-29 03:51 pm (UTC)Coldness triggers northward flight in remigrant monarch butterflies.
Guerra PA, Reppert SM.
Author information
Abstract
Each fall, eastern North American monarch butterflies (Danaus plexippus) migrate from their northern range to their overwintering grounds in central Mexico. Fall migrants are in reproductive diapause, and they use a time-compensated sun compass to navigate during the long journey south. Eye-sensed directional cues from the daylight sky (e.g., the horizontal or azimuthal position of the sun) are integrated in the sun compass in the midbrain central complex region. Sun compass output is time compensated by circadian clocks in the antennae so that fall migrants can maintain a fixed flight direction south. In the spring, the same migrants remigrate northward to the southern United States to initiate the northern leg of the migration cycle. Here we show that spring remigrants also use an antenna-dependent time-compensated sun compass to direct their northward flight. Remarkably, fall migrants prematurely exposed to overwintering-like coldness reverse their flight orientation to the north. The temperature microenvironment at the overwintering site is essential for successful completion of the migration cycle, because without cold exposure, aged migrants continue to orient south. Our discovery that coldness triggers the northward flight direction in spring remigrants solves one of the long-standing mysteries of the monarch migration.
Copyright © 2013 Elsevier Ltd. All rights reserved.
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Date: 2013-12-29 03:52 pm (UTC)Discordant timing between antennae disrupts sun compass orientation in migratory monarch butterflies.
Guerra PA, Merlin C, Gegear RJ, Reppert SM.
Author information
Abstract
To navigate during their long-distance migration, monarch butterflies (Danaus plexippus) use a time-compensated sun compass. The sun compass timing elements reside in light-entrained circadian clocks in the antennae. Here we show that either antenna is sufficient for proper time compensation. However, migrants with either antenna painted black (to block light entrainment) and the other painted clear (to permit light entrainment) display disoriented group flight. Remarkably, when the black-painted antenna is removed, re-flown migrants with a single, clear-painted antenna exhibit proper orientation behaviour. Molecular correlates of clock function reveal that period and timeless expression is highly rhythmic in brains and clear-painted antennae, while rhythmic clock gene expression is disrupted in black-painted antennae. Our work shows that clock outputs from each antenna are processed and integrated together in the monarch time-compensated sun compass circuit. This dual timing system is a novel example of the regulation of a brain-driven behaviour by paired organs.
PMID: 22805565 [PubMed - indexed for MEDLINE]
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Date: 2013-12-29 03:53 pm (UTC)Anatomical basis of sun compass navigation I: the general layout of the monarch butterfly brain.
Heinze S, Reppert SM.
Author information
Abstract
Each fall, eastern North American monarch butterflies (Danaus plexippus) use a time-compensated sun compass to migrate to their overwintering grounds in central Mexico. The sun compass mechanism involves the neural integration of skylight cues with timing information from circadian clocks to maintain a constant heading. The neuronal substrates for the necessary interactions between compass neurons in the central complex, a prominent structure of the central brain, and circadian clocks are largely unknown. To begin to unravel these neural substrates, we performed 3D reconstructions of all neuropils of the monarch brain based on anti-synapsin labeling. Our work characterizes 21 well-defined neuropils (19 paired, 2 unpaired), as well as all synaptic regions between the more classically defined neuropils. We also studied the internal organization of all major neuropils on brain sections, using immunocytochemical stainings against synapsin, serotonin, and γ-aminobutyric acid. Special emphasis was placed on describing the neuroarchitecture of sun-compass-related brain regions and outlining their homologies to other migratory species. In addition to finding many general anatomical similarities to other insects, interspecies comparison also revealed several features that appear unique to the monarch brain. These distinctive features were especially apparent in the visual system and the mushroom body. Overall, we provide a comprehensive analysis of the brain anatomy of the monarch butterfly that will ultimately aid our understanding of the neuronal processes governing animal migration.
Copyright © 2012 Wiley Periodicals, Inc.
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Date: 2013-12-29 03:56 pm (UTC)Migratory connectivity of the monarch butterfly (Danaus plexippus): patterns of spring re-colonization in eastern North America.
Miller NG, Wassenaar LI, Hobson KA, Norris DR.
Author information
Abstract
Each year, millions of monarch butterflies (Danaus plexippus) migrate up to 3000 km from their overwintering grounds in central Mexico to breed in eastern North America. Malcolm et al. (1993) articulated two non-mutually exclusive hypotheses to explain how Monarchs re-colonize North America each spring. The 'successive brood' hypothesis proposes that monarchs migrate from Mexico to the Gulf Coast, lay eggs and die, leaving northern re-colonization of the breeding range to subsequent generations. The 'single sweep' hypothesis proposes that overwintering monarchs continue to migrate northward after arriving on the Gulf coast and may reach the northern portion of the breeding range, laying eggs along the way. To examine these hypotheses, we sampled monarchs throughout the northern breeding range and combined stable-hydrogen isotopes (δD) to estimate natal origin with wing wear scores to differentiate between individuals born in the current vs. previous year. Similar to Malcolm et al. (1993), we found that the majority of the northern breeding range was re-colonized by the first generation of monarchs (90%). We also estimated that a small number of individuals (10%) originated directly from Mexico and, therefore adopted a sweep strategy. Contrary to Malcolm et al. (1993), we found that 62% of monarchs sampled in the Great Lakes originated from the Central U.S., suggesting that this region is important for sustaining production in the northern breeding areas. Our results provide new evidence of re-colonization patterns in monarchs and contribute important information towards identifying productive breeding regions of this unique migratory insect.
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Date: 2013-12-29 03:57 pm (UTC)The monarch butterfly genome yields insights into long-distance migration.
Zhan S, Merlin C, Boore JL, Reppert SM.
Author information
Abstract
We present the draft 273 Mb genome of the migratory monarch butterfly (Danaus plexippus) and a set of 16,866 protein-coding genes. Orthology properties suggest that the Lepidoptera are the fastest evolving insect order yet examined. Compared to the silkmoth Bombyx mori, the monarch genome shares prominent similarity in orthology content, microsynteny, and protein family sizes. The monarch genome reveals a vertebrate-like opsin whose existence in insects is widespread; a full repertoire of molecular components for the monarch circadian clockwork; all members of the juvenile hormone biosynthetic pathway whose regulation shows unexpected sexual dimorphism; additional molecular signatures of oriented flight behavior; microRNAs that are differentially expressed between summer and migratory butterflies; monarch-specific expansions of chemoreceptors potentially important for long-distance migration; and a variant of the sodium/potassium pump that underlies a valuable chemical defense mechanism. The monarch genome enhances our ability to better understand the genetic and molecular basis of long-distance migration.
Copyright © 2011 Elsevier Inc. All rights reserved.
no subject
Date: 2013-12-29 03:58 pm (UTC)Sun compass integration of skylight cues in migratory monarch butterflies.
Heinze S, Reppert SM.
Author information
Abstract
Migrating monarch butterflies (Danaus plexippus) use a time-compensated sun compass to navigate from eastern North America to their overwintering grounds in central Mexico. Here we describe the neuronal layout of those aspects of the butterfly's central complex likely to establish part of the internal sun compass and find them highly homologous to those of the desert locust. Intracellular recordings from neurons in the monarch sun compass network reveal responses tuned to specific E-vector angles of polarized light, as well as azimuth-dependent responses to unpolarized light, independent of spectral composition. The neural responses to these two stimuli in individual neurons are mediated through different regions of the compound eye. Moreover, these dual responses are integrated to create a consistent representation of skylight cues in the sun compass throughout the day. The results advance our understanding of how ambiguous sensory signals are processed by the brain to elicit a robust behavioral response.
© 2011 Elsevier Inc. All rights reserved.
PMID: 21262471 [PubMed - indexed for MEDLINE]
no subject
Date: 2013-12-29 04:00 pm (UTC)Antennal circadian clocks coordinate sun compass orientation in migratory monarch butterflies.
Merlin C, Gegear RJ, Reppert SM.
Author information
Abstract
During their fall migration, Eastern North American monarch butterflies (Danaus plexippus) use a time-compensated Sun compass to aid navigation to their overwintering grounds in central Mexico. It has been assumed that the circadian clock that provides time compensation resides in the brain, although this assumption has never been examined directly. Here, we show that the antennae are necessary for proper time-compensated Sun compass orientation in migratory monarch butterflies, that antennal clocks exist in monarchs, and that they likely provide the primary timing mechanism for Sun compass orientation. These unexpected findings pose a novel function for the antennae and open a new line of investigation into clock-compass connections that may extend widely to other insects that use this orientation mechanism.
no subject
Date: 2013-12-29 04:02 pm (UTC)Defining behavioral and molecular differences between summer and migratory monarch butterflies.
Zhu H, Gegear RJ, Casselman A, Kanginakudru S, Reppert SM.
Author information
Abstract
BACKGROUND:
In the fall, Eastern North American monarch butterflies (Danaus plexippus) undergo a magnificent long-range migration. In contrast to spring and summer butterflies, fall migrants are juvenile hormone deficient, which leads to reproductive arrest and increased longevity. Migrants also use a time-compensated sun compass to help them navigate in the south/southwesterly direction en route for Mexico. Central issues in this area are defining the relationship between juvenile hormone status and oriented flight, critical features that differentiate summer monarchs from fall migrants, and identifying molecular correlates of behavioral state.
RESULTS:
Here we show that increasing juvenile hormone activity to induce summer-like reproductive development in fall migrants does not alter directional flight behavior or its time-compensated orientation, as monitored in a flight simulator. Reproductive summer butterflies, in contrast, uniformly fail to exhibit directional, oriented flight. To define molecular correlates of behavioral state, we used microarray analysis of 9417 unique cDNA sequences. Gene expression profiles reveal a suite of 40 genes whose differential expression in brain correlates with oriented flight behavior in individual migrants, independent of juvenile hormone activity, thereby molecularly separating fall migrants from summer butterflies. Intriguing genes that are differentially regulated include the clock gene vrille and the locomotion-relevant tyramine beta hydroxylase gene. In addition, several differentially regulated genes (37.5% of total) are not annotated. We also identified 23 juvenile hormone-dependent genes in brain, which separate reproductive from non-reproductive monarchs; genes involved in longevity, fatty acid metabolism, and innate immunity are upregulated in non-reproductive (juvenile-hormone deficient) migrants.
CONCLUSION:
The results link key behavioral traits with gene expression profiles in brain that differentiate migratory from summer butterflies and thus show that seasonal changes in genomic function help define the migratory state.
no subject
Date: 2013-12-29 04:03 pm (UTC)This photo of Natural Bridges State Park is courtesy of TripAdvisor
no subject
Date: 2013-12-29 04:10 pm (UTC)Тут с этими монархами такое дело. Сами маленькие, меньше одного грамма особь. Мозг крошечный. Насекомые. Летают сначала с севера на юг 3000 км (из восточной части США в Мексику, и это вроде самая длинная известная миграция насекомых), а потом обратно. Ваши Калифорнийскик - это другая история - они летают зимовать с Западных территорий США в Калифорнию, и кажется перелёт там немного поменьше, но всё равно огромный, как подумать.
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Так вот, есть два вопроса - как они с таким маленьким мозгом знают, куда лететь? В каком виде это записано?
Второй вопрос ещё интереснее - они когда возвращаются из Мексики в восточную часть США, это (вроде бы) не просто так происходит, а с использованием нескольких поколений. То есть, обратно в НЙ возрвращаются бабочки, которые там никогда не были. А родились в Техасе от родителей, которые перезимовали в Мексике. Что должно быть записано у них в мозгу, чтобы долететь в нужное место? Правда, я вот так статьи просмотрела на быструю руку, вроде, на первый взгляд, какая-то часть "старых" бабочек возвращается в НЙ тоже.
no subject
Date: 2013-12-29 04:11 pm (UTC)no subject
Date: 2013-12-29 04:14 pm (UTC)no subject
Date: 2013-12-29 04:15 pm (UTC)я тебе письмо там написала.
no subject
Date: 2013-12-29 04:17 pm (UTC)no subject
Date: 2013-12-29 04:16 pm (UTC)http://www.flightofthebutterflies.com/home/
no subject
Date: 2013-12-29 04:18 pm (UTC)хочу весной подгадать, чтобы поехать пофотографировать.
no subject
Date: 2013-12-29 04:24 pm (UTC)no subject
Date: 2013-12-29 04:26 pm (UTC)no subject
Date: 2013-12-29 04:31 pm (UTC)*
А ваши - не знаю.
Вот ссылка классная - http://www.monarchbutterfly.org/
Далеко это от тебя?
no subject
Date: 2013-12-29 04:33 pm (UTC)мы там в прошлом году проезжали
http://elka-palka.livejournal.com/802770.html
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Date: 2013-12-29 04:35 pm (UTC)Santa Cruz, Natural Bridges State Beach, a site accessible to everyone
no subject
Date: 2013-12-29 04:26 pm (UTC)Которые в Мексике улетают во вторую неделю марта.
А калифорнийских счас поищу.