# Ooths outside hatch in fall in So. Cal?



## cloud jaguar (Oct 29, 2008)

We are currently incubating an ooth of S. Limbata indoors (constant temp between 75-82) yet we put an ooth outside in the garden (day temp 85-97 / night temp 55-65). Well we live in So. Cal and it is hot as Hades here even during this part of fall.

My question is, i noticed today that some spiderlings hatched out in the garden -- aren't they supposed to wait until Spring instead of fall?! And, if the spiderlings hatched, there is probably at least a good chance that the ooth outside in the garden will hatch early and the first frost will kill the nymphs? Is this a cause for concern? Thanks.

~Arkanis


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## sidewinder (Oct 29, 2008)

Arkanis said:


> We are currently incubating an ooth of S. Limbata indoors (constant temp between 75-82) yet we put an ooth outside in the garden (day temp 85-97 / night temp 55-65). Well we live in So. Cal and it is hot as Hades here even during this part of fall. My question is, i noticed today that some spiderlings hatched out in the garden -- aren't they supposed to wait until Spring instead of fall?! And, if the spiderlings hatched, there is probably at least a good chance that the ooth outside in the garden will hatch early and the first frost will kill the nymphs? Is this a cause for concern? Thanks.
> 
> ~Arkanis


Arkanis,

Clearly diapause in various mantid species is not well documented and, from what I can determine, not well studied. The insects where diapause is well documented are usually pest insects and those studies have been undertaken to better understand how one might control the pest.

From what I can discern, there are two possible mechanisms that trigger a diapause in mantid species that don't have an obligate diapause. One would be the photoperiodic induced diapause and the other would be temperature induced diapause. I don't know which mechanism induces diapause in _Stagmomantis limbata_. But, I would guess it was a change in the photoperiod induces embryonic diapause.

Scott


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## Rick (Oct 29, 2008)

Have the wild mantids in your area laid their ooths yet? If so I fail to see the problem. Put it outside already. If you're that worried about it which obviously you are since you have posted about this before then stick it in the fridge for a few weeks until it cools outside some more and then put it outside.


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## sidewinder (Oct 29, 2008)

Rick said:


> Put it outside already.


He already did. He is just wondering if the ootheca will hatch because of how warm it is.

_Stagmomantis limbata_ in nature would have laid oothecae already.

Scott


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## PhilinYuma (Oct 30, 2008)

salomonis said:


> He already did. He is just wondering if the ootheca will hatch because of how warm it is._Stagmomantis limbata_ in nature would have laid oothecae already.
> 
> Scott


You are right and you are wrong, Salamonis. This species has already laid eggs in my area but egglaying is documented as persisting into December in Texas from ootheca laid in Superior, AZ (just north of the Gila River and west of the Coolidge Dam).

Since this is the only species that I own (until next week, Yay!) I have researched it as well as I could and found an excellent old article by a USDA scientist in AESA 30:1, "Biology of the Bordered Mantid, Stagomoomantis Limbata Hahn" available in its entirety (13pp.) on the Internet.

The Bureau of Entomology raised this insect outside, but in captivity, in an "insectary" between 1932 - 1934 for three generations, and though many entomological theories have come and gone since then, this factual report is as valid now as it was then.

During the three years in question, the monthly mean temperature never exceeded 86.3F or fell below F50.1. This is in marked contrast to current temperatures. In Nov. '33, the mean temp was 75.9, today, the high is F89.2, 12F above the modern average. Mean humidity ranged between 54.3% and 70%; yesterday's average was 28%

Of particular interest to me was the fact that in the first generation, the mean average time for males to develope to maturity was 7 days less than the females, but in the next generation, females developed on an average of ten days _faster_ than the males and the third generation was almost a dead heat, and the M:F ratio in all three years was close to 1:1!

All of the mantises hatched out of doors, but the author inferred diapause ("hibernation") from the fact that they wintered as ovae.

All three generations, on average, hatched between early March and early May with a minimum incubation time of 140 days and a maximum of 209.

No eggs were produced by parthenogenesis, but virgin females produced fertile ooths when mated for the first time 50 days after reaching maturity.

Arkanis:

From the recent temperatures that you cite, 85F- 97F, I imagine that you live in SE California (what we refer to as "west of Arizona") -- El Centro, perhaps, Mexicali? So far as I know, though, those towns don't get any frost, do they? S. limbata has only strayed across the Colorado River in the past fifty years or so, but if global warming continues to elevate Fall temperatures, it looks as though nymphs will have to adapt to overwintering or die and join all of those other recently wild critters (remember all of those lovely Malawi cichlids?) that now only exist in captivity.

I have an ootheca that was laid within hours of the female' s capture early this month and which I am wintering outside, now that the temperature is in the low nineties (everyone says, "love the cool weather!"). I shall let you know how it goes. Since it would not be misted in nature, I shall not do so, either


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## sidewinder (Oct 30, 2008)

PhilinYuma said:


> You are right and you are wrong, Salamonis.


PhilinYuma,

Let's back up here a second. Where did I say anything other than _Stagmomantis limbata_ in nature would have laid oothecae already??? I didn't say that _S. limbata_ was done laying oothecae and I didn't say that _S. limbata_ females laid only one ootheca per season.

How am I wrong?

Scott

P.S. Depositing an ootheca without mating is not parthenogenesis. It's only parthenogenesis if the eggs are fertile. The words "diapause" and "hibernation" are not interchangeable. Arkanis lives in Altadena, CA which is next to Pasadena.


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## cloud jaguar (Oct 30, 2008)

Thanks folks - even again today I saw a second recently hatched Green Lynx spider eggcase with mother and spiderlings. It does seem odd to me as I assume they would hatch in early spring.

Scott noted that some years ago mostly S. Californica and Chinese mantis (correct me if wrong). Recently seems mostly S. Limbata from what people around So. Cal post on this list (excepting Woo with the O. Oratoria). That too seems odd if they just crossed the river 50 years ago to become the dominant species some 150 odd miles from the river!

If the dainty and dieting S. Californica that I caught is any measure of the species, then it is no wonder to me that S. Limbatas are everywhere around here and dominant since they are unabashed piglets and avowed chihuahua taunters!

Philinuma, did i understand you correctly that if temps are too hot too early that mantid species that hatch early and are unable to adapt to overwintering may go the way of the Dodo? That would truly be sad.

Plilinuma, could you please post a link to that article you mentioned? I searched for it to no avail. I would love to read that.

~Arkanis


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## sidewinder (Oct 30, 2008)

Arkanis said:


> Thanks folks - even again today I saw a second recently hatched Green Lynx spider eggcase with mother and spiderlings. It does seem odd to me as I assume they would hatch in early spring.


If the Green Lynx spider you found is _Peucetia viridans_, the eggs hatch about this time of year. The species overwinters as early instar spiderlings. So what you are seeing is normal for the species.

Scott


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## sidewinder (Oct 30, 2008)

Arkanis said:


> Scott noted that some years ago mostly S. Californica and Chinese mantis (correct me if wrong). Recently seems mostly S. Limbata from what people around So. Cal post on this list (excepting Woo with the O. Oratoria). That too seems odd if they just crossed the river 50 years ago to become the dominant species some 150 odd miles from the river!


Arkanis,

I never came across _Stagmomantis limbata_ in the Pasadena area some 30 years ago. But that does not mean they were not present. I was just one person and I did not go looking for _S. limbata_. They could have been quite common and I just never looked in the right place at the right time.

Scott


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## PhilinYuma (Oct 30, 2008)

salomonis said:


> PhilinYuma,Let's back up here a second. Where did I say anything other than _Stagmomantis limbata_ in nature would have laid oothecae already??? I didn't say that _S. limbata_ was done laying oothecae and I didn't say that _S. limbata_ females laid only one ootheca per season.
> 
> How am I wrong?
> 
> ...


Bless your rebarbative heart, Salomonis!!

If you simply meant that S. Limbata had laid a couple of oothecae and might well go on to lay some more between now and December, then you are absolutely right!

I never said or thought that parthenogenesis was depositing an infertile ooth (but thanks for the heads up, anyway!), so we agree on that one, too.

I suspect that you have not yet read the article in question. I think that the term "diapause" came into use around the mid thirties, and there is no doubt from the context, that the author was using "hibernation" to mean what we would now call diapause. I did dig out my aged _Fundamentals of Insect Life_ by Metcalf and Flint that came out in 1932, and found no mention of diapause. In their discussion of hibernation, though (p.484), they say: "Some insects that winter in the egg stage do not begin embryonic development until spring..." That sound a lot like daipause to me; what do you think?

Do you have a dog, Salomonis? Mine wants to be walked, so off I go.


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## sidewinder (Oct 30, 2008)

PhilinYuma said:


> Bless your rebarbative heart, Salomonis!!If you simply meant that S. Limbata had laid a couple of oothecae and might well go on to lay some more between now and December, then you are absolutely right!


PhilinYuma,

People tend to get rebarbative when you put words in their mouth (you have done so several times) and say they are wrong when they are not.

When I said that "_Stagmomantis limbata_ in nature would have laid oothecae already", that is exactly what I meant. I don't know why you think I am talking about individual _S. limbata_. As a species, _S. limbata_ has laid oothecae already.

If you look at the context of the comment, it was in response Rick asking if the wild mantids [_S. limbata_] in the area had laid oothecae yet. Yes, they have.

I did not mean, simply or otherwise, that _S. Limbata_ had laid a couple of oothecae and might well go on to lay some more between now and December.

Scott

P.S. William Morton Wheeler, a famous American Entomologist, coined the term "diapause" in 1893.


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## PhilinYuma (Oct 30, 2008)

salomonis said:


> PhilinYuma,
> 
> People tend to get rebarbative when you put words in their mouth (you have done so several times) and say they are wrong when they are not.
> 
> ...


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## cloud jaguar (Oct 30, 2008)

PhilinYuma, could you please post a link to that 13 page report you mentioned about S. Limbata - i cannot find it online. Thanks.


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## PhilinYuma (Oct 31, 2008)

Arkanis said:


> Thanks folks - even again today I saw a second recently hatched Green Lynx spider eggcase with mother and spiderlings. It does seem odd to me as I assume they would hatch in early spring.Scott noted that some years ago mostly S. Californica and Chinese mantis (correct me if wrong). Recently seems mostly S. Limbata from what people around So. Cal post on this list (excepting Woo with the O. Oratoria). That too seems odd if they just crossed the river 50 years ago to become the dominant species some 150 odd miles from the river!
> 
> If the dainty and dieting S. Californica that I caught is any measure of the species, then it is no wonder to me that S. Limbatas are everywhere around here and dominant since they are unabashed piglets and avowed chihuahua taunters!
> 
> ...


Arkanis: I don't know the green lynx spider, but in the past few weeks, black widow egg sacs have been hatching, sending their nasy offspring everywhere. This is the norm here, so perhaps the mantis nymphs will find small food, too.

In the article that I cited (http://chla.library.cornell.edu/cgi/t/text/pageviewer-idx?c=chla;cc=chla;sid=539ff46e38a31a8f4c3e300856fc4560;rgn=full%20text;idno=5077679_146_001;view=image;seq=0115 by the way), the author stated that S. limbata ony occured in Texas, New Mexico and Arizona at the time of writing. Like the European mantis that came to the U.S. as a stowaway, I imagine that S. limbata hitched a ride on trucks bringing lechuga, bails of hay and what-have-you down the I8. The pinchy migra that stop cars as they enter California probably would't recognize one if they looked right at it.

The Yuman strain do more than taunt chihuahuas. This morning I had to go and buy crickets for the mantises because I had run out of flies, and they were eyeing my lab in a distictly predatory way. When I caught them, I had nothing to feed them and tossed them a few few fire ants. They chewed them down, mandibles, stingers, and all (as you know, they don't use formic acid for trail laying), but now that they are pampered, they don't look at them.

I would guess that the fate of nymphs that hatch in the fall would depend less on the availability of food (though I don't know that from direct observation, of course) than on the occurence of a frost deep enough to kill them. I didn't think that you had frosts in Pasadena, at least in most years, though, but you mention frost, so am I wrong? Frost is definitely not a problem here.

My lone ootheca is sitting outside now. If it hatches, I shall bring the nymphs in doors to watch them grow. I'll let you know what happens and hope that you do likewise.


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## sidewinder (Oct 31, 2008)

PhilinYuma,

The way you used the word "parthenogenesis" suggested you thought it was something different than what it is. I can only go by what you write.

In regards to diapause versus hibernation, here you go:

http://www.diapausefoundation.org/index.php?link=education

Scott


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## sidewinder (Oct 31, 2008)

Arkanis said:


> Philinuma, did i understand you correctly that if temps are too hot too early that mantid species that hatch early and are unable to adapt to overwintering may go the way of the Dodo? That would truly be sad.Plilinuma, could you please post a link to that article you mentioned? I searched for it to no avail. I would love to read that.


Arkanis,

I read the article. The tests were conducted outdoors in Uvalde, TX, which is just outside San Antonio. It states that _Stagmomantis limbata_ produced only one generation per year. The oothecae were laid starting in August and did not hatch until about March 1st.

Considering how hot it is in the San Antonio area in August through September and into October, I don't see how facultative diapause in _S. limbata_ could be induced by anything other than a change in photoperiod for that study. It doesn't get cold soon enough to induce diapause before the oothecae would hatch. But it is possible that either cold or photoperiod could induce diapause.

If the diapause was obligate, then colder temperatures would be needed to break diapause. But I have been told the only mantid in the US that has an obligate diapause is _Mantis religiosa_.

All very interesting!

Scott


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## PhilinYuma (Oct 31, 2008)

salomonis said:


> PhilinYuma,
> 
> The way you used the word "parthenogenesis" suggested you thought it was something different than what it is. I can only go by what you write.
> 
> ...


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## darkspeed (Oct 31, 2008)

I absolutely love the recent addition of so many brilliant, highly educated minds on this board. It makes for some very interesting, highly entertaining, if not somewhat pointless arguements. :lol: 

"Kicked to death by a canary" HA!!!! I love it.

You just made my day Phill!


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## sidewinder (Oct 31, 2008)

PhilinYuma,

My goal was technical accuracy which I think is important when discussing technical subjects. Yours appears to be payback....

You used a conjunction to connect the absence of parthenogenesis with delayed oothecae oviposition. Maybe you can see how one would incorrectly infer your meaning. By the way, I misspoke in regards to parthenogenesis. I said "It's only parthenogenesis if the eggs are fertile." That's incorrect. It's only parthenogenesis if unfertilized eggs hatch.

The Raiford A. Roberts article that you reference was written in 1937. William Morton Wheeler coined the term "diapause" in 1893. The last time I checked, 1893 came before 1937.

Scott


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## kamakiri (Oct 31, 2008)

DARKSPEED said:


> I absolutely love the recent addition of so many brilliant, highly educated minds on this board. It makes for some very interesting, highly entertaining, if not somewhat pointless arguements. :lol: "Kicked to death by a canary" HA!!!! I love it.
> 
> You just made my day Phill!


+1  

But I thought there was only *one* brilliant, highly educated mind added to the board lately  ...and I certainly don't make the cut!


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## PhilinYuma (Nov 1, 2008)

_Pecca fortiter!_

Have you more experienced members noted that sometimes our posts wander slightly off a thread's topic?

The question in this one was whether S. limbata nymphs hatched in October in Pasaden CA could survive the Pasadena winter. My guess is that they will not, due to the cold and lack of suitably sized prey.

Less obvious is the answer to the subsequent question about diapause in the ootheca of mantis species indigenous to the southwestern states, and I can claim, without fear of contradiction, that some of my responses comprised a clusterfunk (cute US military expression, "cockup" in the British Army) of factual and interpretive errors.

Firstly, contrary to what I said or implied, Pasadena, Yuma (indeed, all of Yuma County) and San Antonio all experience frost during the winter. My error partly arose from examining the nightly temperatures in December and January in these three cities without realizing that "frost can occur on grass and other exposed surface objects, while the temperature of the free air only a few feet above the ground is several degress higher than this critical temperature."

More importantly, I tacitly but wrongly implied that freezing was a prerequisite for diapause, while of course it is not. Ootheca stored in captivity and kept in the refrigerator for a period (any agreement on how long -- four- five weeks?) never experience an ambient temperature below freezing.

It seems to me that ootheca from locally caught, indigenous mantises are most easily and safely wintered outside, where it is not necessary to second guess how much humidity they need. Are many members doing this? I shall be doing this with my two S. limbata ooths, but if my female lays a third (go girl!) I shall winter it indoors, compare results and report them here in the spring.


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## sidewinder (Nov 1, 2008)

PhilinYuma,

Actually, the original question involved some new spiderlings in his garden and whether or not they should have hatched this time of year and if that meant that the _Stagmomantis limbata_ ootheca in the same garden would hatch early too.

Based on what I can recall of my 27 years living in Pasadena and the local area, there just aren't enough prey insects available to sustain a population of mantids during the winter. Even though the winters are mild, it seems most insects go into their typical winter mode, whatever that might be for each species. There are time periods where significant frost each morning is common. In other words, what you say about winter and food supplies in your last post are correct. If _S. limbata_ hatched in October or November, they would not survive long.

But that still does answer the original questions.

Arkanis later told us he believed the spiderlings to be Green Lynx spiders. If they are _Peucetia viridans_, then it is normal for the spiderlings to hatch this time of year since they overwinters as early instar spiderlings. In other words, these spiderlings being present means nothing in regards to the _S. limbata_ ootheca.

So we are left with these questions:

Because of the extended warm weather, is there a good chance that the _S. limbata_ ootheca outside in the garden will hatch early and the first frost will kill the nymphs? Is this a cause for concern?

This is why the discussion correctly focused on diapause. As I said before I don't know what kind of diapause that _S. limbata_ goes through.

I have been told that only one species of mantid in the U.S.A. goes through an obligate embryonic diapause (i.e. a required diapause) and that is _Mantis religiosa_. If _S. limbata_ went through an obligate embryonic diapause, it wouldn't matter how long warm weather persisted after their oothecae were laid because a period of colder weather would be needed to break the diapause.

So let's assume _S. limbata_ supports a facultative embryonic diapause. In other words, diapause is not required but entered if certain conditions present themselves. The two mechanisms that make the most sense for facultative embryonic diapause in _S. limbata_ are photoperiod and temperature. Photoperiod is the most likely since higher temperatures persist long enough for the oothecae laid early in the season to incubate and hatch.

If we assume the facultative embryonic diapause for _S. limbata_ is caused by photoperiod, there is no reason to worry that an _S. limbata_ ootheca placed outside in the garden will hatch early so there is no cause for concern.

Having said all of that, it will be very interesting to hear what actually happens with the various oothecae that Arkanis and you incubate indoors and outdoors. We should soon know if the diapause for _S. limbata_ is obligatory or facultative.

This thread stayed mostly on topic and has been quite interesting. I certainly have enjoyed it.

Scott


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## darkspeed (Nov 1, 2008)

Going a little off topic is not really much concern to me... it happens to almost every thread. I just find it amusing that the smarter, more knowlegable or more educated the contributers are the more the disagreements seem to be about the smaller, less significant details, and sometimes it boils down to my _______ is bigger or better than yours. Again I am certainly not complaining, as I find it to be rather entertaining and quite interesting.


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## kamakiri (Nov 1, 2008)

Well, the difficult part is that sometimes a whole point hinges on the details.

I've seen a LOT of assumptions about diapause and its requirements. But it think the typical opinions on the subject are a little too narrow.

Arguing gets tiresome...but I did want to make a point about the open hostility, which I think is not necessary


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## sidewinder (Nov 1, 2008)

kamakiri said:


> I've seen a LOT of assumptions about diapause and its requirements. But it think the typical opinions on the subject are a little too narrow.


Do you care to elaborate on this? What assumptions do you have a problem with? What opinions are too narrow?

Scott


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## MantidLord (Nov 1, 2008)

salomonis said:


> Do you care to elaborate on this? What assumptions do you have a problem with? What opinions are too narrow?Scott


Oh my goodness just let it go.


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## kamakiri (Nov 1, 2008)

salomonis said:


> Do you care to elaborate on this? What assumptions do you have a problem with? What opinions are too narrow?Scott


It's the general opinions of what I've read...here and otherwise in the scientific community. I think we have the tendency to oversimplify.

Regarding diapause trigger or requirements, it's the thinking that there's a finite temp or daylight threshold to begin or finish diapause. What if it's both? What if it's more of a range? What if it's just a delta of either or both? So many factors to consider beyond our expertise, in this forum and in the world.

If we look back in recent history, we can see how far along we are in the workings of biological mechanisms. It only makes me think of how little we actually know. Both you and I have been studying such subjects since the '70s...I thought it was all reasonable and factual back then...I think a lot of it has since proven to be false or only partly correct. That's one of the main things that makes me very skeptical of everything I read, even if it is current.


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## PhilinYuma (Nov 1, 2008)

salomonis said:


> PhilinYuma,
> 
> Actually, the original question involved some new spiderlings in his garden and whether or not they should have hatched this time of year and if that meant that the _Stagmomantis limbata_ ootheca in the same garden would hatch early too.
> 
> ...


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## sidewinder (Nov 1, 2008)

kamakiri,

As I said in my first post in this thread, clearly diapause in various mantid species is not well documented and, from what I can determine, not well studied.

There is a lengthy article discussing diapause in the _Encyclopedia of Insects_ (Resh and Cardé, 2003) that is quite good.

In the article, the facultative pupal diapause of _Sarcophaga bullata_, the Flesh fly, is used as an example. It shows what percentage of _S. bullata_, kept at 25° C, entered pupal diapause at what photoperiod. When the photoperiod was longer than 14 hours, no _S. bullata_ entered pupal diapause. But, when the photoperiod was 13.5 hours or less, about 85 percent of the _S. bullata_ entered pupal diapause. Lower the temperature the _S. bullata_ pupa are kept at to 18° C, and nearly 100 percent entered pupal diapause when the photoperiod was 13.5 hours or less. Temperature doesn't trigger the diapause, but lower temperatures do increase the likelihood of it being induced.

The embryonic diapause of _Bombyx mori_, the Silkworm, is discussed because it is the best understood. _Bombyx mori_ uses a hormonal mechanism to enter diapause. Interestingly, the hormone is present in the embryos only if the mother's embryo was subject to an appropriately short photoperiod.

While the exact mechanisms at the molecular level are still unclear, the environmental cues are well understood. The knowledge of the hormonal signals fall somewhere in between.

Scott


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## sidewinder (Nov 1, 2008)

PhilinYuma said:


> You often mention photoperiod as a possible mediator of diapause, Salomonis, and while I know that it is a common mechanism and much more reliable than temperature fluctuation, I can't dig up anything that posits this phenomenon in mantids. Do you have any articles, web pages or "personal correspondence" that throws any light [sad pun emoticon here] on this? My thought is that since a lot of people have successfully raised this species (S. limbata] indoors without regard to photoperiod, it is probably not a factor.


PhilinYuma,

The reason I suspect photoperiod as what induces diapause in _Stagmomantis limbata_ is that, in the southwest anyway, using temperature would be unreliable. Oothecae laid early in the season would be exposed to warm temperatures for a very long time. Temperature may play a part, but I don't see how it could be the primary motivator.

The photoperiod experienced by oothecae kept inside is dictated by the lights inside, not the day length outside.

Scott


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## PhilinYuma (Nov 1, 2008)

salomonis said:


> PhilinYuma,
> 
> The photoperiod experienced by oothecae kept inside is dictated by the lights inside, not the day length outside.
> 
> ...


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## sidewinder (Nov 1, 2008)

PhilinYuma,

I'm confused. All I am saying is that a short enough photoperiod will induce a diapause and I don't think temperature could be the primary inducer since that would be so unreliable. The reason being how warm the temperatures can stay, in the southwest, well into October and even November. Basing diapause on day length would be ultra reliable since that is extremely consistent.

All it would take would be one extra long warm season in an area to kill out an entire species in the area if entering diapause were based on temperature alone. Using temperature to break diapause makes a lot of sense. But not as a reason to enter diapause in the south west United States.

Scott


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## PhilinYuma (Nov 2, 2008)

salomonis said:


> PhilinYuma,
> 
> I'm confused. All I am saying is that a short enough photoperiod will induce a diapause and I don't think temperature could be the primary inducer since that would be so unreliable. The reason being how warm the temperatures can stay, in the southwest, well into October and even November. Basing diapause on day length would be ultra reliable since that is extremely consistent.
> 
> ...


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## sidewinder (Nov 2, 2008)

PhilinYuma,

It will be interesting to see the results of your experiment. I look forward to hearing what happens with the _Stagmomantis limbata_ ootheca that Arkanis has incubating inside as well.

As I said, I have suspicions but no facts when it comes to my ideas regarding diapause in _S. limbata_. The only data I have says that most incidences of facultative embryonic diapause in insects are induced by photoperiod. Add that to the sustained warm temperatures in _S. limbata_'s range well after the oothecae are laid, and I feel pretty good about what I suppose. But, it the diapause could very well be brought on by colder temperatures. Or, it could be an obligate diapause. We'll no more soon I suspect.

Scott


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## darkspeed (Nov 2, 2008)

My experience with ootheca is limited...of the ones I have had, the ones that did hatch did so without much help... that is, I put them in the same environmental conditions my mantids are kept in and they hatched just like that. They were all tropical species as well.... So my question is:

Is lower than optimum temps the only way to postpone hatching? How else would you keep a tropical ooth from hatching? Obviously they arent expecting a cold period, and I am afraid introducing one would be detrimental, but sometimes I would like to have a little more control over when they do hatch.

Secondly. You guys have frequently mentioned southwestern warmness, and there is no denying that is does stay warmer longer in the southwest. However, though I have not experienced it for myself, it is my understanding that nights in the desert can get brutally cold, and dip down as far as 40f even in non winter months. If my understanding is correct, then in an arid region like the southwest, wouldnt it be possible that an exceptionally cool september or october night followed by a reasonably warm day for that time of year could initiate a premature temp based diapause followed by a subsequently premature hatching?


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## sidewinder (Nov 2, 2008)

DARKSPEED,

I don't have any experience trying to slow down the hatching of oothecae from tropical species so I can't tell if there are any side effects of using cooler temperatures to in an attempt to do so.

Deserts and high deserts get cold at night in the winter months, with high deserts getting much colder. During the summer months, it is not uncommon to have night time temperatures in the high 90°s F in the desert.

Pasadena in not either of those though. Here is the average low temperatures for Pasadena for the months that matter in regards to this situation:

March - 52° F

April - 54° F

May - 58° F

June - 61° F

July - 65° F

August - 66° F

September - 65° F

October - 60° F

_Stagmomantis limbata_ start laying oothecae in late August and they hatch from early March to early May. A warm October could see a little more than two full months of warm temperatures at night for oothecae laid in late August. If photoperiod where not a factor, there is no reason not to believe that some oothecae would hatch before the cold set in.

Once diapause is entered, I am sure it takes a long period of cold temperatures to break the diapause. Probably in the range of several months of sub 60°. Then it would take periods of warm temperatures over 70° to cause the oothecae to hatch.

Again, I don't know for sure that _S. limbata_ does not have an obligate embryonic diapause. If it does not, I do not know what induces the facultative embryonic diapause. But, considering the climate of the habitat of _S. limbata_, photoperiod makes the most the sense. That along with photoperiod being the most common inducer of facultative embryonic diapause in the insect world, makes me feel comfortable positing photoperiod as the inducer.

Maybe we will get some data in the next few weeks to months that will enlighten us on the subject.

Scott


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## kamakiri (Nov 2, 2008)

salomonis said:


> As I said in my first post in this thread, clearly diapause in various mantid species is not well documented and, from what I can determine, not well studied.


I think we agree on that note. It is part of why I feel the discussion should not be so tightly defined.

Even some of the phrases we've used could be erroneous from the beginning. We can say things like, "enter diapause"...but my feeling is that it is possible for a temperate species to oviposit directly into a state of diapause. Changing that assumption could mean exiting diapause would only require a positive delta T. We should also not be looking too hard at the months or conditions where the ooths hatch...but perhaps a month or two before...when the ebryos start developing...or just finish developing.

Just more food for thought...

It would be nice if we had solid examples for mantids similar to your flesh fly example.

---------

Still trying to figure out what parameters I'm going to test with my _religiosa_ ooths. My 7th was laid this morning.


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## sidewinder (Nov 2, 2008)

kamakiri,

Well, maybe we should define some terms here so we are clear:

Obligate embryonic diapause: This form of diapause happens each generation and is not induced by environmental cues. The diapause is entered at some state in the development of the embryo. This could be at fertilization, when the first instar is just about to hatch, or somewhere in between. Typically, some period of chilling is required to break the diapause and temperature or photoperiod are the cues to start development again.

Facultative embryonic diapause: Environmental cues are used to determine whether or not to enter diapause. These cues include photoperiod and temperature. The diapause is entered at some state in the development of the embryo. Typically, some period of chilling is required to break the diapause and temperature or photoperiod are the cues to start development again.

In facultative embryonic diapause, there is a prediapause period. It is during this period that environmental cues are evaluated. I can find no reference to suggest that facultative embryonic diapause can be initiated by the mother. That would imply an obligate embryonic diapause since environmental factors present for the embryos would not factor into entering diapause.

In areas where photoperiod vary significantly, photoperiod is the normal impetus to enter facultative diapause since it is much more reliable than temperature as a cue. It is common for temperature to enhance the photoperiod response. Near the equator, where the photoperiod does not vary much, temperature is the normal impetus to enter facultative diapause.

From what I understand, most _Mantis religiosa_ in the USA have an obligate embryonic diapause. But it is possible some groups in more southern areas support a facultative embryonic diapause. I don't know if that means Florida only or if that might include southern California and parts of Texas.

Scott


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## PhilinYuma (Nov 2, 2008)

DARKSPEED said:


> You guys have frequently mentioned southwestern warmness, and there is no denying that is does stay warmer longer in the southwest. However, though I have not experienced it for myself, it is my understanding that nights in the desert can get brutally cold, and dip down as far as 40f even in non winter months. If my understanding is correct, then in an arid region like the southwest, wouldnt it be possible that an exceptionally cool september or october night followed by a reasonably warm day for that time of year could initiate a premature temp based diapause followed by a subsequently premature hatching?


It doesn't seem likely, Darkspeed, since one cald night and one warm day don't seem to induce hatching. It's good to hear, though that someone beside me is interested in the fate of those poor little hatchlings. Nature ("whatever we understand it to be") seems to have much more leeway built into its mechanisms than we sometimes give it credit for. I don't think that an ooth laid in the beginninmg of October and then exposed to a very cold night and a hot day (and at least in this area, such a sequence of events would be very rare), would come to harm, but if it did, then the ooths laid in November by the same females would survive. A much more serious disaster would be something like a brush fire, again very unusual, but not impossible, in December. In that case, the whole generation, adults (soon to die anyway) ooths and all would be lost, and next year there would be no S. limbata in that area. Furthermore, the new growth vegetation may well be unsuitable for this insect, so it might not support a new population for years. But as soon as it became suitable, S. limbata would come flocking back (and I am talking about a parapatric population here), like Sooners when Oklahoma was opened up to settlers.

If the destroyed population was allopatric, though, like some (imaginary) island in the middle of the Colorado River, it is just as likely that the ecological niche once occupied by our favorite mantis would be taken over by another species altogether. We sometimes hear that "Nature doesn't care about the individual, only the species." What nonsense! Nature (or nature) doesn't care, period! I have been harping on this nihilistic view of nature for a few posts now I realize, but I don't know of any other view (Intelligent Design, anyone? LOL!) that fits the facts.

Sunny, peering over my shoulder, like a vengeful troll, made two comments. "Don't you worry about insulting the believers in ID?" [No] and "You used 'sympatric' when you should have said 'parapatric', and if you don't know what the words mean, why should anyone else?" Well I corrected the error, and the answer is that I am lazy and sometimes use a technical word to avoid explaining what it means. For anyone who might not have met the patric family and doesn't find this post exciting enough to bother Googling them, when considering different populations of the same species (in this case), a population cut off from its fellows, like Brazil_Fisherman's Taiwan popluation, is alloptric; two or more populations that are contiguous are parapatric, and two or more different species sharing the same area are sympatric.

Time to take my dog for a walk and a certain smart assed kid home.


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## sidewinder (Nov 2, 2008)

PhilinYuma said:


> An ooth that was maintained in an environment that recieved a consistent ammount of light and still hatched would tend to negate the photoperiod contention, but an otherwise unaccountable failure to hatch under these conditions would support it.Is this fun or not!


PhilinYuma,

I just read this again and am now quite confused. What do you mean by "consistent amount of light"?

Here are my experiments:

1. Take a freshly laid _Stagmomantis limbata_ ootheca and kept it at a temperature warm enough to incubate the eggs (75° F) AND gave it the right kind of light (blue-light) for 18 hours per day. If it hatched in about two months, it would not disprove or prove the photoperiod induced diapause theory. All it would prove is that the _S. limbata_ does not have an obligate diapause.

2. Take a freshly laid _S. limbata_ ootheca and kept it at a temperature warm enough to incubate the eggs (75° F) but keep it in the dark. If it hatched in about two months, that would disprove the photoperiod induced diapause theory. Conversely, if it did not hatch, this experiment in conjunction with a hatch in the experiment above, would prove the photoperiod induced diapause theory.

These experiments would not be hard to undertake. But it would be important to use freshly laid oothecae just to make sure the important segment of the prediapause period was not missed. This segment would be where the environmental cues are evaluated and the diapause "decision" was made.

Clearly these experiments would need to be repeated many times to verify the results. Once photoperiod or temperature was establish as the diapause inducer, experiments could be undertaken to determine thresholds.

Scott


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## PhilinYuma (Nov 2, 2008)

salomonis said:


> PhilinYuma,I just read this again and am now quite confused. What do you mean by "consistent amount of light"?
> 
> Scott


Well, Salamonis, that's an easy one. We have been discussing the fact that outside, a steady decrease in photoperiod up until December 22nd might affect diapause. Perhaps "consistent photoperiod" will make more sense, though a shortening of photoperiod from one day to the next would provide a smaller amount of light and consistent photoperiods would provide a consistent ammount, particularly indoors, where the light would cease as soon as the light was turned off instead of waning slowly as it does in nature.

A seemingly picky but, I think, very important note: One experiment, as you indicate at the end of your post, would not "prove" anything, but merely be consistent with one theory or the other. Your experiments sound fine. Do you have any ooths?


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## sidewinder (Nov 3, 2008)

PhilinYuma said:


> Well, Salamonis, that's an easy one. We have been discussing the fact that outside, a steady decrease in photoperiod up until December 22nd might affect diapause.


No. That's not what I have been discussing anyway. Photoperiod length is the environmental cue, not the fact that there is a gradual decrease in photoperiod. The facultative pupal diapause of Sarcophaga bullata, the Flesh fly I mentioned in a earlier post in this thread, is an example of this. The 13.5 hour photoperiod is what induced diapause. Decreasing photoperiod would be an illogical environmental cue since the photoperiod would still have to be measured and there would still be a photoperiod threshold that would need to be crossed.



PhilinYuma said:


> A seemingly picky but, I think, very important note: One experiment, as you indicate at the end of your post, would not "prove" anything, but merely be consistent with one theory or the other. Your experiments sound fine. Do you have any ooths?


Not seemingly. It is picky because clearly I did not mean "absolute fact proved beyond any doubt" since I said the experiments would need to be repeated many times to verify the results. In science the word "proof" is used often and my experiment would provide "proof". Independent experiments would need to be conducted to verify my proof. But it is still proof in the scientific sense of the word.

No, I do not have freshly laid _Stagmomantis limbata_ oothecae at my disposal. Nor I am interested in raising the species or any temperate species for that matter.

Scott


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## PhilinYuma (Nov 3, 2008)

salomonis said:


> No. That's not what I have been discussing anyway. Photoperiod length is the environmental cue, not the fact that there is a gradual decrease in photoperiod. The facultative pupal diapause of Sarcophaga bullata, the Flesh fly I mentioned in a earlier post in this thread, is an example of this. The 13.5 hour photoperiod is what induced diapause. Decreasing photoperiod would be an illogical environmental cue since the photoperiod would still have to be measured and there would still be a photoperiod threshold that would need to be crossed.Scott


Salamonis:

I clearly misunderstood you. The photoperiod needs to fall below that which obtains when the ooth is laid, is that right? If so, an ooth laid on Dec 3rd (the latest date given by Roberts, so probably close enough), would have an absolute maximum of 19 days before the days started getting longer, even if the trigger were the photoperiod of the shortest day, which seems statistically unlikely. If the trigger period occured on Novenber 5th, though, it would go immediately into diapause. Most stimuli responses seem to be "fuzzy" (as in "fuzzy logic"). There does not appear to be a specific temperature or duration of that temperature that induces or or fails to induce diapause, but the experiment results for S. bullata seem chillingly exact and clinical, and of course, it is quite a leap to infer that mantis physiology should closely aproximate that of flesh flies and silk moths. Still, I don't have a major problem with it as an unsupported possibility.

"Not seemingly. It is picky because clearly I did not mean "absolute fact proved beyond any doubt" since I said the experiments would need to be repeated many times to verify the results. In science the word "proof" is used often and my experiment would provide "proof". Independent experiments would need to be conducted to verify my proof. But it is still proof in the scientific sense of the word."

No, you are wrong on this one, unless there is some "scientific sense" that hasn't found its way into the etymological or scientific dictionaries. Remember the good old null hypothesis? I even tried Webster's NID in the hope that you might be right. No luck, though. When I said "picky", I was trying to be non confrontational (God, it's hard!).

No, I do not have freshly laid _Stagmomantis limbata_ oothecae at my disposal. Nor I am interested in raising the species or any temperate species for that matter.

Then I guess that your experimental models were for the benefit of the rest of us. Of course, if you were to conduct the experiment, and I am sure that you would do so meticulously,you wouldn't have to raise the fry. You could always flush them or feed them to your exotic species.


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## sidewinder (Nov 3, 2008)

PhilinYuma said:


> > Not seemingly. It is picky because clearly I did not mean "absolute fact proved beyond any doubt" since I said the experiments would need to be repeated many times to verify the results. In science the word "proof" is used often and my experiment would provide "proof". Independent experiments would need to be conducted to verify my proof. But it is still proof in the scientific sense of the word.
> 
> 
> No, you are wrong on this one, unless there is some "scientific sense" that hasn't found its way into the etymological or scientific dictionaries. I even tried Webster's NID in the hope that you might be right. No luck, though.


PhilinYuma,

This is ridiculous.

Let's look at the first definition of "proof" in the _American Heritage Dictionary_:

"The evidence or argument that compels the mind to accept an assertion as true."

How about this first definition from Dictionary.com:

"evidence sufficient to establish a thing as true, or to produce belief in its truth."

The experiments I suggested would provide "proof". It may not be good "proof" to some, but it is "proof" none the less. "Proof" is not infallible by definition.

Scott


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## sidewinder (Nov 3, 2008)

PhilinYuma said:


> I clearly misunderstood you. The photoperiod needs to fall below that which obtains when the ooth is laid, is that right? If so, an ooth laid on Dec 3rd (the latest date given by Roberts, so probably close enough), would have an absolute maximum of 19 days before the days started getting longer, even if the trigger were the photoperiod of the shortest day, which seems statistically unlikely. If the trigger period occured on Novenber 5th, though, it would go immediately into diapause. Most stimuli responses seem to be "fuzzy" (as in "fuzzy logic"). There does not appear to be a specific temperature or duration of that temperature that induces or or fails to induce diapause, but the experiment results for S. bullata seem chillingly exact and clinical, and of course, it is quite a leap to infer that mantis physiology should closely aproximate that of flesh flies and silk moths. Still, I don't have a major problem with it as an unsupported possibility.


PhilinYuma,

Why do you assume the embryo in the ootheca would use the photoperiod of the day they were laid as a basis to calculate an environmental cue? The cue would undoubtedly be a critical day length as seen in _Sarcophaga bullata_. It may not be as sharp a demarcation though. The fact that the photoperiod was getting shorter would not necessarily be important. The fact that a particular photoperiod threshold was crossed would be. That would indicate the type of winter to expect.

I have no idea what that critical day length would be for any other insect than _S. bullata_.

I don't know why you consider it quite a leap that mantid physiology would be the similar to other species in the class _Insecta_ in regards to how photoperiod is detected and used as an environmental cue for diapause. Look how similar our physiology is to other species in the class _Mammalia_.

Scott


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## Orin (Nov 3, 2008)

salomonis said:


> The reason I suspect photoperiod...


What mechanism do you imagine allows the developing eggs to 'see through' the egg exterior and ootheca and why don't different layers of eggs hatch at different times (or not hatch at all)? Daily seasonal temperature shifts can provide a similar effect but photoperiod would require a specialize organ.

Sometimes trees put out their leaves too early and get frozen, sometimes mantis oothecae hatch too early due to long duration temperature or humidity shifts but not all of them react the same or many extant species would be extinct. The unreliability of weather shifts necessitates that not all oothecae from the same species (or even the same female) will hatch at the same time under the same or very slightly different conditions. For husbandry purposes we look for a general rule rather than the odd exception (some people fall off a ten story building or eat poison and live but those aren't requirements for a human caresheet). In all probability the _S. limbata _ootheca won't hatch out early.


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## PhilinYuma (Nov 3, 2008)

salomonis said:


> No, you are wrong on this one, unless there is some "scientific sense" that hasn't found its way into the etymological or scientific dictionaries. I even tried Webster's NID in the hope that you might be right. No luck, though.PhilinYuma,
> 
> This is ridiculous.
> 
> Scott


Salomonis:

I think that you are right, Salomonis. There is definitely something ridiculous going on here. Have you ever thought of submitting a scientific paper for publication? If so, you may find it difficult to get it published if your experimental data is based on an observed population of one. Scientists always carp about those darned variables. Perhaps we could agree to settle for a "smidgin of proof", or possibly a "prooficle"? I'd go with that.


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## PhilinYuma (Nov 3, 2008)

Orin said:


> For husbandry purposes we look for a general rule rather than the odd exception (some people fall off a ten story building or eat poison and live but those aren't requirements for a human caresheet).


Orin:

Do you have one of those human caresheets? It might come in handy.

"In all probability the _S. limbata _ootheca won't hatch out early."

You're right about that, mate. And if it doesn't, "there'll be something, something to carry on." Damned fine song, (Laura Nero?) even if I don't remember all the words.


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## sidewinder (Nov 3, 2008)

PhilinYuma,

I would not publish a scientific paper with the proof available from two different tests done with two different oothecae. That is why I said "Clearly these experiments would need to be repeated many times to verify the results." A little bit of "proof" is still proof. The simple fact is that the word "proof" does not mean "truth". "Proof" is evidence or authentication.

Scott


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## sidewinder (Nov 3, 2008)

Orin said:


> What mechanism do you imagine allows the developing eggs to 'see through' the egg exterior and ootheca and why don't different layers of eggs hatch at different times (or not hatch at all)? Daily seasonal temperature shifts can provide a similar effect but photoperiod would require a specialize organ.


Light can penetrate more than 5mm into soil. Does the proteinaceous material oothecae are made of block light or allow light of the appropriate wavelength through? Other insects that go through a diapause have specialized extraretinal photoreceptors. Why not mantid embryos? Temperature is not reliable, especially in more southern temperate zones.

I am only arguing that photoperiod as an environmental cue makes the most sense since it the most reliable. We won't know which environmental cue, photoperiod or temperature, is actually used to induce diapause in _Stagmomantis limbata_ until someone does those experiments I suggested and does them several times to verify results.

Scott


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## PhilinYuma (Nov 3, 2008)

salomonis said:


> PhilinYuma,"I would not publish a scientific paper with the proof available from two different tests done with two different oothecae."
> 
> Scott


Sounds like a plan, Salomonis! Perhaps this part of the thread is best summed up by a tag from Cervantes' _ Don Quixote_, "the proof of the ooth is in the hatching." I'm not sure if that is exactly right, my Castillian sucks, but he seemed to have a "quotable quote" for nearly everything, and many are stiil current in modern English; things like "quit while you're ahead," "the pot calling the kettle black," and of course, "tilting at windmills." Often though, I abreviate that first one to just the first word.


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## Orin (Nov 4, 2008)

salomonis said:


> Other insects that go through a diapause have specialized extraretinal photoreceptors. Why not mantid embryos?


Which insects are those and which ones have embryonic photoreceptors?


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## sidewinder (Nov 4, 2008)

Orin said:


> Which insects are those and which ones have embryonic photoreceptors?


Any insect that enters diapause based on photoperiod cues taken as an embryo. Specific diapause information is hard to find. But here are a few examples I could find:

_Sarcophaga crassipalpis_: this species experiences a diapause in the pupal stage that is induced by experiencing short photoperiods during the second half of embryonic development.

_Bombyx mori_: this species experiences an embryonic diapause if the mother experienced short photoperiods during her embryonic development.

_Aedes triseriatus_: experiences embryonic diapause induced by photoperiod during its own embryonic stage.

_Aedes albopictus_: temperate Japan, experiences embryonic diapause induced by photoperiod during its own embryonic stage.

_Neodiprion sertifer_: experiences embryonic diapause induced by photoperiod during its own embryonic stage.

I am sure I could find more. Actually, I did find many more _Aede_ spp. but decided listing them all would be tedious. The bottom line is that there are many general descriptions of facultative embryonic diapause induced by photoperiod. Talk to an entomologist and you will find this concept ordinary.

Diapause is a well understood event. But, only species that are pests or have other economic impact appear to have their diapause mechanisms studied in detail and published. Hence the dearth of specific information.

Scott


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## Christian (Nov 4, 2008)

I was asked to answer on this topic. To be generous, it was too long and redundant to be read completely. I will try to clarify some points, though, so that future discussions don't repeat futile arguments but have a base.

First of all, you have to distinguish between diapause and quiescence. Diapause is induced *before* conditions gets worse and, once induced, need a trigger to be finished. Quiescence is an ultimate response to unfavorable conditions, as low temperatures.

In mantids, at least in those species studied in this regard, diapause (whether facultative or not) is induced by photoperiod and fixed by temperature. This is: a decrease in photoperiod induces diapause preparation, but this can be achieved only before a certain embryonic state. That's why early laid ooths sometimes hatch in fall. Diapause is, once induced, fixed by a special embryonic membrane. During diapause, mild days in winter and spring cannot induce a hatch. Only after winter, embryonic develpment is continued and nymphs will hatch in spring. In species with overwintering nymphs, diapause includes a development stop and a low metabolic rate (_Empusa_).

Quiescence, on the other hand, is induced by unfavorable conditions (e. g. low temps) and ends immidiately as conditions become better. Some populations of _Blepharopsis mendica_ may undergo this kind of hibernation.

However, some species or populations with facultative diapause can overwinter as eggs or as nymphs, depending on the severity of the winter (e. g. _Ameles decolor_). So, if winter temps get higher, mantids may switch to a larval hibernation state. In fact, overwintering as a nymphs is the more widespread state and occurs almost everywhere south of the 10° C isocline. The spread into more northern habitats required a switch to egg overwintering. Animals, insects in particular, have some well developed adaptive abilities, so warmer winters may not necessarily lead to extinction, but to a change in life history. This change may initially cause some population declines, and, subsequently, a changed species assemblage (rare species may become common and common ones rare), but extinction due to climate changes is a minor threat to mantids (due to a mostly large distribution) - in contrast to some other taxon...


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## Orin (Nov 4, 2008)

salomonis said:


> I am sure I could find more. Actually, I did find many more _Aede_ spp. but decided listing them all would be tedious. The bottom line is that there are many general descriptions of facultative embryonic diapause induced by photoperiod. Talk to an entomologist and you will find this concept ordinary.


Just because you type a few key words into a search engine doesn't mean what you pull up is relevant. Bombyx diapause is related to day length experienced by the adult  moth which has eyes and, if you've ever kept them, the eggs don't hatch without a cold period. I imainge all your other examples are also off track as well.

As for talking to an entomologist, you apparently have no understanding of entomology or you'd realize it's a massive field and entomologists specialize and only those specializing in orthopteroid insects would have anything but very basic knowledge of mantids.


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## sidewinder (Nov 4, 2008)

Orin said:


> Just because you type a few key words into a search engine doesn't mean what you pull up is relevant. Bombyx diapause is related to day length experienced by the adult  moth which has eyes and, if you've ever kept them, the eggs don't hatch without a cold period. I imainge all your other examples are also off track as well.As for talking to an entomologist, you apparently have no understanding of entomology or you'd realize it's a massive field and entomologists specialize and only those specializing in orthopteroid insects would have anything but very basic knowledge of mantids.


Orin,

Let me quote from page 309 of the _Encyclopedia of Insects_ (Resh and Cardé, 2003). Which, by the way, is a well respected publication and was emphatically recommended to me by an Entomologist acquaintance of mine:

"The best understood hormonal mechanism regulating embryonic diapause is based on the silkworm. In this species diapause intercedes early during embryogenesis, just before segmentation. The development fate of the embryo is determined by the presence or absence of diapause hormone (DH), a neuropeptide secreted by the mother's subesophageal ganglion. In the presence of DH, the ovariole produces eggs that enter diapause, and when the hormone is not present the eggs develop without the interruption of diapause. Whether the mother releases DH is dependent upon the photoperiod she was exposed to as an embryo. Thus, the mother's photoperiodic history dictates whether she will release the DH needed to influence the diapause fate of her progeny."

I will also quote page 166 of _Insect Hormones_ by H. Frederik Nijhout:

"The control of embryonic diapause has been best studied in the Chinese silkworm _Bombyx mori_. Some races of _Bombyx_ have an obligatory embryonic diapause, and thus have only one generation per year; they are univoltine. The embryos of other races of _Bombyx_, however, undergo a facultative diapause, and such races can have more than one generation each year. Whether or not an embryo from such a race will enter diapause depends on the photoperiod that its mother experienced while she herself was an embryo."

In regards to the eyes being used to gather photoperiodic information, let me provide a quote from page 308 of the _Encyclopedia of Insects_ (Resh and Cardé, 2003):

"Photoperiodic information is perceived through a receptor in the brain, integrated and stored in the brain, and then translated into endocrine events that control the induction and maintenance of diapause. The location of the photoreceptor responsible for the measurement of daylength has been studied in relatively few insects, but in most of them the compound eyes and ocelli are not the conduit for this information. Surgical destruction of these visual centers or coating the eyes with an opaque paint usually does not interfere with the photoreception involved in the programming of diapause. The photoperiodic signal appears to impinge directly on the brain, but the exact location of these extraretinal photoreceptors has not been elucidated."

Finally, a quote from page 158 of _The Insects_ by Gullan and Cranston:

"Insects can detect day-length or night-length changes (photoperiod stimuli), sometimes with extreme accuracy, through brain photoreceptors rather than compound eye or ocelli. The insect brain also stores the programing for diapause..."

Yes, I have raised _Bombyx mori_ and, if I can recall from experiences 40+ years ago, the ones I raised needed the eggs to be chilled for a while. But clearly that is not always the case based on the information I have provided here. I suspect your information saying the "Bombyx diapause is related to day length experienced by the adult moth which has eyes" is incorrect. What basis do you have for challenging my other examples?

I very well understand that entomology covers an expansive and growing list of species with specialization the most common path taken by those that pursue it. I considered a career as an Entomologist many years ago. But, to your point, insects in the Order _Orthoptera_ are not the only insects that take cues from the photoperiod. They are not the only insects that implement diapause. While the molecular mechanisms of diapause are varied and not well understood, the environmental cues are and I suspect most entomologist have at least a basic understanding of those cues since diapause is covered in even the most basic classroom textbooks. You don't need to be a mantid expert to know that mantids breathe through spiracles.

Scott


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## sidewinder (Nov 4, 2008)

Christian,

Thank you for posting that information.

Scott


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## Orin (Nov 4, 2008)

salomonis said:


> But, to your point, insects in the Order _Orthoptera_ are not the only insects that take cues from the photoperiod. They are not the only insects that implement diapause. While the molecular mechanisms of diapause are varied and not well understood, the environmental cues are and I suspect most entomologist have at least a basic understanding of those cues since diapause is covered in even the most basic classroom textbooks. You don't need to be a mantid expert to know that mantids breathe through spiracles.Scott


Christian already told you there's no data to support your theory (so did others of course). Your arguement never ceases to die in the face of facts or information.

Orthopteroids are not the same thing as Orthopterans, different levels. Maybe one in a hundred entomologists would know offhand the specifics of Bombyx diapause, maybe not even that many since it's related to a race that probably can't be acquired. Comparing species race specific diapause to the name of a general body part is beyond misleading. There are ten different comments I could respond to but you're way off topic and there's only so much time in the day.


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## Peter Clausen (Nov 5, 2008)

A note from Mantidforum Administration:

This topic was closed for..."quality control purposes". I have re-opened it. I encourage all members with concerns about treatment between members to contact myself or one of the other moderators on this forum. The "Report" button is located on the lower left side of the box surrounding each post. Complaints are to be made privately.

Thank you.


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## PhilinYuma (Nov 5, 2008)

Christian: Thanks for sorting that so that even I could understand it!

Slomonis. Now if we could just get a post from one of those Japanese scientists to straighten us out on Bombyx mori......


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## PhilinYuma (Nov 5, 2008)

Christian: Thanks for sorting that so that even I could understand it! That does it for me!

Salomonis. Now if we could just get a post from one of those Japanese scientists to straighten us out on Bombyx mori......


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## sidewinder (Nov 5, 2008)

Orin said:


> Christian already told you there's no data to support your theory (so did others of course). Your arguement never ceases to die in the face of facts or information.Orthopteroids are not the same thing as Orthopterans, different levels. Maybe one in a hundred entomologists would know offhand the specifics of Bombyx diapause, maybe not even that many since it's related to a race that probably can't be acquired. Comparing species race specific diapause to the name of a general body part is beyond misleading. There are ten different comments I could respond to but you're way off topic and there's only so much time in the day.


Orin,

What Christian wrote substantially agrees with my posit that diapause in _Stagmomantis limbata_ is photoperiod induced and is terminated by a chilling period. But there are no experiment data to support that claim specific to _S. limbata_. Starting with my very first post in this thread, I have been consistent on this. Based on available information, photoperiod induced diapause makes the most sense, at least to me. But experiments would need to be done to verify that, one way or the other.

What facts or information have been presented that contradicts my theory that diapause in _Stagmomantis limbata_ is photoperiod induced and is terminated by a chilling period?

When you wrote "Orthopteroid", in my mind I read "Orthopteran". My mistake. The point I was making still applies. An Entomologist would not have to be all that familiar with mantids to have insights into their physiology.

_Bombyx mori_ was mentioned to you in direct response to your question "Which insects are those and which ones have embryonic photoreceptors?". I said I suspect most entomologist have at least a basic understanding of the environmental cues that induce diapause. I never suggested that most entomologist would have detailed knowledge of any particular species diapause.

The details of _B. mori_ diapause are only relevant because they are an example of an insect with embryonic photoreceptors. However, you seem to think the _Bombyx_ races that supports the facultative diapause are probably unobtainable. Yet, one source I cited doesn't mention the obligate diapause directly and the other uses the phrases "Some races of _Bombyx_ have an obligatory embryonic diapause" and "other races of _Bombyx_, however, undergo a facultative diapause". To me, "some" doesn't mean "most" and "other" doesn't mean "few". A third published source that I didn't quote (_The Insects_ by Gullan and Cranston) mentions how optimal silk production comes from silkworms that go through an embryonic diapause but how, for production reasons, they would prefer to use eggs that didn't go through a diapause. A quick search on that horrible Internet will find scores more references to this facultative diapause. Either a lot of scientists have access to this _Bombyx_ "race that probably can't be acquired" or this facultative diapause is actually common. You even said that "Bombyx diapause is related to day length experienced by the adult moth" [incorrect]. Which diapause would that be? An obligatory egg diapause would take no environmental cues from the adult moth. So is this "adult moth" one of those races that probably cannot be obtained?

I am not sure what you mean by "Comparing species race specific diapause to the name of a general body part is beyond misleading". The only comparing I did was to show that several species of insects support an embryonic diapause induced by photoperiod. This means those embryos have some mechanism that allows them to evaluate the photoperiod. The data I found suggests specialized extraretinal photoreceptors. Is that the mechanism used by mantid embryos that evaluate photoperiod? Not known. But, the fact that other insects use this method makes it a reasonable possibility.

The discussion of the various positions in this thread have had many twists and turns and most all the "way off topic" information I have presented has been done to address specific "on topic" challenges to my theories. I am more than willing to abandon my theories if verifiable information is presented that shows they are not plausible. No where have I said that my theories are the only theories that could be correct. I have defended my theories with information available on the Internet and in books to which I have access. I have used the same sources to argue against theories that make less sense to me. My goal is not to be right. My goal is to get to the right conclusion, whatever it might be. Part of that process is having opposing points of view debate the merits of their respective theories and ideas. This is what fosters discovery and learning for all who participate. I certainly have learned quite a lot because of this thread. To argue for a theory, you have to learn all you can about the underlying details. The same is true if you want to argue against a theory.

It would certainly be more productive if you used actual arguments to contradict my theories and ideas instead of just saying I was wrong or I didn't understand. If you aren't willing to do that, so what you say can be discussed and learned from, why post at all?

At the end of the day, we still don't have a conclusive answer. Maybe we will get some better data from some of the experiments being undertaken.

Scott


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