Here is the abstract of a paper investigating the mechanisms by which Monarch butterflies navigate during their long migrations. The authors created a simulation implementing their proposed mechanism and collected data on actual Monarch butterflies for comparison to the simulation results.
Migrating eastern North American monarch butterflies use a time-compensated sun compass to adjust their flight to the southwest direction. Although the antennal genetic circadian clock and the azimuth of the sun are instrumental for proper function of the compass, it is unclear how these signals are represented on a neuronal level and how they are integrated to produce flight control. To address these questions, we constructed a receptive field model of the compound eye that encodes the solar azimuth. We then derived a neural circuit model that integrates azimuthal and circadian signals to correct flight direction. The model demonstrates an integration mechanism, which produces robust trajectories reaching the southwest regardless of the time of day and includes a configuration for remigration. Comparison of model simulations with flight trajectories of butterflies in a flight simulator shows analogous behaviors and affirms the prediction that midday is the optimal time for migratory flight.
Eli Shlizerman, James Phillips-Portillo, Daniel B. Forger, Steven M. Reppert. Neural Integration Underlying a Time-Compensated Sun Compass in the Migratory Monarch Butterfly. Cell Reports, 2016 DOI:10.1016/j.celrep.2016.03.057
The paper is described in a ScienceDaily article: Scientists crack secrets of the Monarch butterfly’s internal compass.
BA: Here is the abstract of a paper investigating the mechanisms by which Monarch butterflies navigate during their long migrations.
RM: I just skmmed the article; it would take me some time to figure out exactly what their model is. But it looks very interesting and it sure seems like the “matching” of azimuth and timing signal (that I think is what they propose) is a controlled perceptual variable.
RM: It turns out that there is a Monarch butterfly winter migration destination right near the UCSB campus that I didn’t know about when I was there but discovered a few years ago. It an amazing sight to see these huge pods of what must be many thousands of butterflies hanging from branches in a eucalyptus grove by the sea (the Monarchs not only navigate well, they have great taste in winter vacation resorts).
Best
Rick
The authors created a simulation implementing their proposed mechanism and collected data on actual Monarch butterflies for comparison to the simulation results.
Migrating eastern North American monarch butterflies use a time-compensated sun compass to adjust their flight to the southwest direction. Although the antennal genetic circadian clock and the azimuth of the sun are instrumental for proper function of the compass, it is unclear how these signals are represented on a neuronal level and how they are integrated to produce flight control. To address these questions, we constructed a receptive field model of the compound eye that encodes the solar azimuth. We then derived a neural circuit model that integrates azimuthal and circadian signals to correct flight direction. The model demonstrates an integration mechanism, which produces robust trajectories reaching the southwest regardless of the time of day and includes a configuration for remigration. Comparison of model simulations with flight trajectories of butterflies in a flight simulator shows analogous behaviors and affirms the prediction that midday is the optimal time for migratory flight.
Eli Shlizerman, James Phillips-Portillo, Daniel B. Forger, Steven M. Reppert. Neural Integration Underlying a Time-Compensated Sun Compass in the Migratory Monarch Butterfly. Cell Reports, 2016 DOI:10.1016/j.celrep.2016.03.057
The paper is described in a ScienceDaily article: Scientists crack secrets of the Monarch butterfly’s internal compass.
BA: Here is the abstract of a paper investigating the mechanisms by which Monarch butterflies navigate during their long migrations.
RM: I just skmmed the article; it would take me some time to figure out exactly what their model is. But it looks very interesting and it sure seems like the “matching” of azimuth and timing signal (that I think is what they propose) is a controlled perceptual variable.
BA: I did the same and also did not get a good sense of their model, but clearly it functions as a control system for compass heading. It was nice to see the model being simulated and evaluated against real data.
If you go to the website for the paper there is a tab that takes you to supplemental material, including several videos showing a butterfly graphic surrounded by compass points. The azimuth position of the sun is also indicated, as well as the time. As the video runs, you can see the “butterfly� turning (like a compass needle) to the reference heading, with some small degree of damped oscillation around that position.
RM: It turns out that there is a Monarch butterfly winter migration destination right near the UCSB campus that I didn’t know about when I was there but discovered a few years ago. It an amazing sight to see these huge pods of what must be many thousands of butterflies hanging from branches in a eucalyptus grove by the sea (the Monarchs not only navigate well, they have great taste in winter vacation resorts).
BA: I wouldn’t mind migrating there myself!
Bruce
···
The authors created a simulation implementing their proposed mechanism and collected data on actual Monarch butterflies for comparison to the simulation results.
Migrating eastern North American monarch butterflies use a time-compensated sun compass to adjust their flight to the southwest direction. Although the antennal genetic circadian clock and the azimuth of the sun are instrumental for proper function of the compass, it is unclear how these signals are represented on a neuronal level and how they are integrated to produce flight control. To address these questions, we constructed a receptive field model of the compound eye that encodes the solar azimuth. We then derived a neural circuit model that integrates azimuthal and circadian signals to correct flight direction. The model demonstrates an integration mechanism, which produces robust trajectories reaching the southwest regardless of the time of day and includes a configuration for remigration. Comparison of model simulations with flight trajectories of butterflies in a flight simulator shows analogous behaviors and affirms the prediction that midday is the optimal time for migratory flight.
Eli Shlizerman, James Phillips-Portillo, Daniel B. Forger, Steven M. Reppert. Neural Integration Underlying a Time-Compensated Sun Compass in the Migratory Monarch Butterfly. Cell Reports, 2016 DOI:10.1016/j.celrep.2016.03.057
The paper is described in a ScienceDaily article: Scientists crack secrets of the Monarch butterfly’s internal compass.
BA: Here is the abstract of a paper investigating the mechanisms by which Monarch butterflies navigate during their long migrations.
RM: I just skmmed the article; it would take me some time to figure out exactly what their model is. But it looks very interesting and it sure seems like the “matching” of azimuth and timing signal (that I think is what they propose) is a controlled perceptual variable.
BA: I did the same and also did not get a good sense of their model, but clearly it functions as a control system for compass heading. It was nice to see the model being simulated and evaluated against real data.
If you go to the website for the paper there is a tab that takes you to supplemental material, including several videos showing a butterfly graphic surrounded by compass points. The azimuth position of the sun is also indicated, as well as the time. As the video runs, you can see the “butterfly� turning (like a compass needle) to the reference heading, with some small degree of damped oscillation around that position.
RM: It turns out that there is a Monarch butterfly winter migration destination right near the UCSB campus that I didn’t know about when I was there but discovered a few years ago. It an amazing sight to see these huge pods of what must be many thousands of butterflies hanging from branches in a eucalyptus grove by the sea (the Monarchs not only navigate well, they have great taste in winter vacation resorts).
BA: I wouldn’t mind migrating there myself!
Bruce
The authors created a simulation implementing their proposed mechanism and collected data on actual Monarch butterflies for comparison to the simulation results.
Migrating eastern North American monarch butterflies use a time-compensated sun compass to adjust their flight to the southwest direction. Although the antennal genetic circadian clock and the azimuth of the sun are instrumental for proper function of the compass, it is unclear how these signals are represented on a neuronal level and how they are integrated to produce flight control. To address these questions, we constructed a receptive field model of the compound eye that encodes the solar azimuth. We then derived a neural circuit model that integrates azimuthal and circadian signals to correct flight direction. The model demonstrates an integration mechanism, which produces robust trajectories reaching the southwest regardless of the time of day and includes a configuration for remigration. Comparison of model simulations with flight trajectories of butterflies in a flight simulator shows analogous behaviors and affirms the prediction that midday is the optimal time for migratory flight.
Eli Shlizerman, James Phillips-Portillo, Daniel B. Forger, Steven M. Reppert. Neural Integration Underlying a Time-Compensated Sun Compass in the Migratory Monarch Butterfly. Cell Reports, 2016 DOI:10.1016/j.celrep.2016.03.057
The paper is described in a ScienceDaily article: Scientists crack secrets of the Monarch butterfly’s internal compass.
From: Warren Mansell [mailto:wmansell@gmail.com] Sent: Tuesday, April 19, 2016 6:10 AM To: csgnet@lists.illinois.edu Subject: Re: Controlling Butterflies
WM: Any discussion of whether these guys need to know about PCT? And if not, have they converged on a model that doesn’t explicitly require it? If so, what theory is that model based on?
Warren
BA: I will need to read the paper much more carefully before I can answer those questions maybe in a day or two.
BA: Here is the abstract of a paper investigating the mechanisms by which Monarch butterflies navigate during their long migrations.
RM: I just skmmed the article; it would take me some time to figure out exactly what their model is. But it looks very interesting and it sure seems like the “matching” of azimuth and timing signal (that I think is what they propose) is a controlled perceptual variable.
BA: I did the same and also did not get a good sense of their model, but clearly it functions as a control system for compass heading. It was nice to see the model being simulated and evaluated against real data.
If you go to the website for the paper there is a tab that takes you to supplemental material, including several videos showing a butterfly graphic surrounded by compass points. The azimuth position of the sun is also indicated, as well as the time. As the video runs, you can see the âbutterflyâ? turning (like a compass needle) to the reference heading, with some small degree of damped oscillation around that position.
RM: It turns out that there is a Monarch butterfly winter migration destination right near the UCSB campus that I didn’t know about when I was there but discovered a few years ago. It an amazing sight to see these huge pods of what must be many thousands of butterflies hanging from branches in a eucalyptus grove by the sea (the Monarchs not only navigate well, they have great taste in winter vacation resorts).
BA: I wouldnât mind migrating there myself!
Bruce
The authors created a simulation implementing their proposed mechanism and collected data on actual Monarch butterflies for comparison to the simulation results.
Migrating eastern North American monarch butterflies use a time-compensated sun compass to adjust their flight to the southwest direction. Although the antennal genetic circadian clock and the azimuth of the sun are instrumental for proper function of the compass, it is unclear how these signals are represented on a neuronal level and how they are integrated to produce flight control. To address these questions, we constructed a receptive field model of the compound eye that encodes the solar azimuth. We then derived a neural circuit model that integrates azimuthal and circadian signals to correct flight direction. The model demonstrates an integration mechanism, which produces robust trajectories reaching the southwest regardless of the time of day and includes a configuration for remigration. Comparison of model simulations with flight trajectories of butterflies in a flight simulator shows analogous behaviors and affirms the prediction that midday is the optimal time for migratory flight.
Eli Shlizerman, James Phillips-Portillo, Daniel B. Forger, Steven M. Reppert. Neural Integration Underlying a Time-Compensated Sun Compass in the Migratory Monarch Butterfly. Cell Reports, 2016 DOI:10.1016/j.celrep.2016.03.057
The paper is described in a ScienceDaily article: Scientists crack secrets of the Monarch butterflyâs internal compass.
A model for what? And whether they need to know PCT depends on
whether they need it to bring their perceptions nearer their
reference values. They got a publication that will be cited, didn’t
they? They didn’t need PCT for that, which I presume was something
they were controlling for.
Whether PCT explains the butterflies’ ability to converge on very
small areas in Mexico and Santa Barbara is another question. I don’t
think they have even shown what perceptions the butterflies are
controlling, because I did not see that they had performed the TCV
using the main type if duisturbance faced by the butterflies –
wind.
They showed, so far as I can see, that the butterflies can control
for pointing in a reference direction near SW, but they haven’t
shown how the butterflies can control for proceeding South West when
disturbed by winds from all directions. Butterflies float pretty
well on the wind, like flotsam in an ocean current, so, since they,
or at least a lot of them, do arrive at the wintering place, they
must be able to perceive the direction toward that place even after
having been blown way off a direct course.
Nor have they shown whether butterflies that start from different
places have different reference values for the direction to the
small area where millions of them arrive after dealing with these
various winds. In other words, I think they showed that butterflies
have the sensory equipment needed to control for heading direction
(Since I was child, I have used the same technique myself, though I
use a watch rather than an internal estimator of time), but that’s a
far cry from showing how the butterflies get where they want to go.
Martin
···
On 2016/04/19 6:10 AM, Warren Mansell
wrote:
Any discussion of whether these guys need to know about PCT?
And if not, have they converged on a model that doesn’t
explicitly require it? If so, what theory is that model based
on?
Warren
On 18 Apr 2016, at 22:44, Bruce Abbott < >
wrote:
[From Bruce Abbott (2016.04.18.1740
EDT)]
Â
Rick Marken (2016.04.18.0730) –
Bruce
Abbott (2016.04.17.1000 EST)
BA:
Here is the abstract of a paper investigating
the mechanisms by which Monarch butterflies
navigate during their long migrations.Â
RM: I just skmmed the article;
it would take me some time to figure out exactly
what their model is. But it looks very interesting
and it sure seems like the “matching” of azimuth
and timing signal (that I think is what they
propose) is a controlled perceptual variable.Â
Â
BA: I did the same and also did
not get a good sense of their model, but clearly
it functions as a control system for compass
heading. It was nice to see the model being
simulated and evaluated against real data.
Â
If you go to the website for
the paper there is a tab that takes you to
supplemental material, including several videos
showing a butterfly graphic surrounded by compass
points. The azimuth position of the sun is also
indicated, as well as the time. As the video
runs, you can see the “butterfly� turning (like a
compass needle) to the reference heading, with
some small degree of damped oscillation around
that position.
Â
RM: It turns out that there is
a Monarch butterfly winter migration destination
right near the UCSB campus that I didn’t know
about when I was there but discovered a few years
ago. It an amazing sight to see these huge pods of
what must be many thousands of butterflies hanging
from branches in a eucalyptus grove by the sea
(the Monarchs not only navigate well, they have
great taste in winter vacation resorts).
Â
BA: I wouldn’t mind migrating
there myself!
Â
Bruce
Â
The
authors created a simulation implementing
their proposed mechanism and collected data on
actual Monarch butterflies for comparison to
the simulation results.
Â
Migrating
eastern North American monarch butterflies
use a time-compensated sun compass to adjust
their flight to the southwest direction.
Although the antennal genetic circadian
clock and the azimuth of the sun are
instrumental for proper function of the
compass, it is unclear how these signals are
represented on a neuronal level and how they
are integrated to produce flight control. To
address these questions, we constructed a
receptive field model of the compound eye
that encodes the solar azimuth. We then
derived a neural circuit model that
integrates azimuthal and circadian signals
to correct flight direction. The model
demonstrates an integration mechanism, which
produces robust trajectories reaching the
southwest regardless of the time of day and
includes a configuration for remigration.
Comparison of model simulations with flight
trajectories of butterflies in a flight
simulator shows analogous behaviors and
affirms the prediction that midday is the
optimal time for migratory flight.
Â
Eli
Shlizerman, James Phillips-Portillo, Daniel
B. Forger, Steven M. Reppert. ** Neural Integration
Underlying a Time-Compensated Sun
Compass in the Migratory Monarch
Butterfly**. * Cell
Reports*, 2016 DOI:10.1016/j.celrep.2016.03.057
Barb P: They used to land on the LARC observatory (Lindheimer Astronomical Research Center) where Dad worked. I don’t recall seeing it myself, but I remember Mom talking about how the entire structure was absolutely covered in butterflies! I wonder where they had gone before this observatory was built, and after it was dismantled?
I witnessed the monarchs myself a couple of decades ago at the top of Green Mountain outside Boulder, CO, blanketing a large area on a number of giant boulders and pine trees. It would be interesting to know if it was the same group who spent the night in Evanston. If so, it looks as if they were making a bee-line (!) across the US, so directional sense makes sense.
I’ve read it has to do with length of day and temperature, although temperature doesn’t make sense since the mountains would be considerably cooler than the lakeshore in Illinois. Perhaps they’re going where the lead guy made the reservations…
Any discussion of whether these guys need to know about PCT?
And if not, have they converged on a model that doesn’t
explicitly require it? If so, what theory is that model based
on?
Warren
A model for what? And whether they need to know PCT depends on
whether they need it to bring their perceptions nearer their
reference values. They got a publication that will be cited, didn’t
they? They didn’t need PCT for that, which I presume was something
they were controlling for.
Whether PCT explains the butterflies' ability to converge on very
small areas in Mexico and Santa Barbara is another question. I don’t
think they have even shown what perceptions the butterflies are
controlling, because I did not see that they had performed the TCV
using the main type if duisturbance faced by the butterflies –
wind.
They showed, so far as I can see, that the butterflies can control
for pointing in a reference direction near SW, but they haven’t
shown how the butterflies can control for proceeding South West when
disturbed by winds from all directions. Butterflies float pretty
well on the wind, like flotsam in an ocean current, so, since they,
or at least a lot of them, do arrive at the wintering place, they
must be able to perceive the direction toward that place even after
having been blown way off a direct course.
Nor have they shown whether butterflies that start from different
places have different reference values for the direction to the
small area where millions of them arrive after dealing with these
various winds. In other words, I think they showed that butterflies
have the sensory equipment needed to control for heading direction
(Since I was child, I have used the same technique myself, though I
use a watch rather than an internal estimator of time), but that’s a
far cry from showing how the butterflies get where they want to go.
Martin
On 18 Apr 2016, at 22:44, Bruce Abbott <bbabbott@frontier.com >
wrote:
[From Bruce Abbott (2016.04.18.1740
EDT)]
Â
Rick Marken (2016.04.18.0730) –
Bruce
Abbott (2016.04.17.1000 EST)
BA:
Here is the abstract of a paper investigating
the mechanisms by which Monarch butterflies
navigate during their long migrations.Â
RM: I just skmmed the article;
it would take me some time to figure out exactly
what their model is. But it looks very interesting
and it sure seems like the “matching” of azimuth
and timing signal (that I think is what they
propose) is a controlled perceptual variable.Â
Â
BA: I did the same and also did
not get a good sense of their model, but clearly
it functions as a control system for compass
heading. It was nice to see the model being
simulated and evaluated against real data.
Â
If you go to the website for
the paper there is a tab that takes you to
supplemental material, including several videos
showing a butterfly graphic surrounded by compass
points. The azimuth position of the sun is also
indicated, as well as the time. As the video
runs, you can see the “butterfly� turning (like a
compass needle) to the reference heading, with
some small degree of damped oscillation around
that position.
Â
RM: It turns out that there is
a Monarch butterfly winter migration destination
right near the UCSB campus that I didn’t know
about when I was there but discovered a few years
ago. It an amazing sight to see these huge pods of
what must be many thousands of butterflies hanging
from branches in a eucalyptus grove by the sea
(the Monarchs not only navigate well, they have
great taste in winter vacation resorts).
Â
BA: I wouldn’t mind migrating
there myself!
Â
Bruce
Â
The
authors created a simulation implementing
their proposed mechanism and collected data on
actual Monarch butterflies for comparison to
the simulation results.
Â
Migrating
eastern North American monarch butterflies
use a time-compensated sun compass to adjust
their flight to the southwest direction.
Although the antennal genetic circadian
clock and the azimuth of the sun are
instrumental for proper function of the
compass, it is unclear how these signals are
represented on a neuronal level and how they
are integrated to produce flight control. To
address these questions, we constructed a
receptive field model of the compound eye
that encodes the solar azimuth. We then
derived a neural circuit model that
integrates azimuthal and circadian signals
to correct flight direction. The model
demonstrates an integration mechanism, which
produces robust trajectories reaching the
southwest regardless of the time of day and
includes a configuration for remigration.
Comparison of model simulations with flight
trajectories of butterflies in a flight
simulator shows analogous behaviors and
affirms the prediction that midday is the
optimal time for migratory flight.
Â
Eli
Shlizerman, James Phillips-Portillo, Daniel
B. Forger, Steven M. Reppert. ** Neural Integration
Underlying a Time-Compensated Sun
Compass in the Migratory Monarch
Butterfly**. * Cell
Reports*, 2016 DOI:10.1016/j.celrep.2016.03.057
Barb P: They used to land on the LARC observatory (Lindheimer Astronomical Research Center) where Dad worked. I don’t recall seeing it myself, but I remember Mom talking about how the entire structure was absolutely covered in butterflies! I wonder where they had gone before this observatory was built, and after it was dismantled?
I witnessed the monarchs myself a couple of decades ago at the top of Green Mountain outside Boulder, CO, blanketing a large area on a number of giant boulders and pine trees. It would be interesting to know if it was the same group who spent the night in Evanston. If so, it looks as if they were making a bee-line (!) across the US, so directional sense makes sense.
I’ve read it has to do with length of day and temperature, although temperature doesn’t make sense since the mountains would be considerably cooler than the lakeshore in Illinois. Perhaps they’re going where the lead guy made the reservations…
Any discussion of whether these guys need to know about PCT?
And if not, have they converged on a model that doesn’t
explicitly require it? If so, what theory is that model based
on?
Warren
A model for what? And whether they need to know PCT depends on
whether they need it to bring their perceptions nearer their
reference values. They got a publication that will be cited, didn’t
they? They didn’t need PCT for that, which I presume was something
they were controlling for.
Whether PCT explains the butterflies' ability to converge on very
small areas in Mexico and Santa Barbara is another question. I don’t
think they have even shown what perceptions the butterflies are
controlling, because I did not see that they had performed the TCV
using the main type if duisturbance faced by the butterflies –
wind.
They showed, so far as I can see, that the butterflies can control
for pointing in a reference direction near SW, but they haven’t
shown how the butterflies can control for proceeding South West when
disturbed by winds from all directions. Butterflies float pretty
well on the wind, like flotsam in an ocean current, so, since they,
or at least a lot of them, do arrive at the wintering place, they
must be able to perceive the direction toward that place even after
having been blown way off a direct course.
Nor have they shown whether butterflies that start from different
places have different reference values for the direction to the
small area where millions of them arrive after dealing with these
various winds. In other words, I think they showed that butterflies
have the sensory equipment needed to control for heading direction
(Since I was child, I have used the same technique myself, though I
use a watch rather than an internal estimator of time), but that’s a
far cry from showing how the butterflies get where they want to go.
Martin
On 18 Apr 2016, at 22:44, Bruce Abbott <bbabbott@frontier.com >
wrote:
[From Bruce Abbott (2016.04.18.1740
EDT)]
Â
Rick Marken (2016.04.18.0730) –
Bruce
Abbott (2016.04.17.1000 EST)
BA:
Here is the abstract of a paper investigating
the mechanisms by which Monarch butterflies
navigate during their long migrations.Â
RM: I just skmmed the article;
it would take me some time to figure out exactly
what their model is. But it looks very interesting
and it sure seems like the “matching” of azimuth
and timing signal (that I think is what they
propose) is a controlled perceptual variable.Â
Â
BA: I did the same and also did
not get a good sense of their model, but clearly
it functions as a control system for compass
heading. It was nice to see the model being
simulated and evaluated against real data.
Â
If you go to the website for
the paper there is a tab that takes you to
supplemental material, including several videos
showing a butterfly graphic surrounded by compass
points. The azimuth position of the sun is also
indicated, as well as the time. As the video
runs, you can see the “butterfly� turning (like a
compass needle) to the reference heading, with
some small degree of damped oscillation around
that position.
Â
RM: It turns out that there is
a Monarch butterfly winter migration destination
right near the UCSB campus that I didn’t know
about when I was there but discovered a few years
ago. It an amazing sight to see these huge pods of
what must be many thousands of butterflies hanging
from branches in a eucalyptus grove by the sea
(the Monarchs not only navigate well, they have
great taste in winter vacation resorts).
Â
BA: I wouldn’t mind migrating
there myself!
Â
Bruce
Â
The
authors created a simulation implementing
their proposed mechanism and collected data on
actual Monarch butterflies for comparison to
the simulation results.
Â
Migrating
eastern North American monarch butterflies
use a time-compensated sun compass to adjust
their flight to the southwest direction.
Although the antennal genetic circadian
clock and the azimuth of the sun are
instrumental for proper function of the
compass, it is unclear how these signals are
represented on a neuronal level and how they
are integrated to produce flight control. To
address these questions, we constructed a
receptive field model of the compound eye
that encodes the solar azimuth. We then
derived a neural circuit model that
integrates azimuthal and circadian signals
to correct flight direction. The model
demonstrates an integration mechanism, which
produces robust trajectories reaching the
southwest regardless of the time of day and
includes a configuration for remigration.
Comparison of model simulations with flight
trajectories of butterflies in a flight
simulator shows analogous behaviors and
affirms the prediction that midday is the
optimal time for migratory flight.
Â
Eli
Shlizerman, James Phillips-Portillo, Daniel
B. Forger, Steven M. Reppert. ** Neural Integration
Underlying a Time-Compensated Sun
Compass in the Migratory Monarch
Butterfly**. * Cell
Reports*, 2016 DOI:10.1016/j.celrep.2016.03.057
![Bill325pct[1].jpg](http://discourse.iapct.org/uploads/default/original/1X/2b402f1607d914ef55d1722cee9ee5f7b22d20d9.jpeg)
