Do stagmomantis ooths really need to diapause???

[agent A]

Diapause might not always be necessary and it certainly would not make sense in a situation where the warmer seasons are long enough that an ootheca has to sit for longer than it can without significant losses to experience a change from warmer weather to cooler weather and back. Egg development is affected by the temperature as we have all observed that cooler temperatures mean later hatch dates, so it is more likely that the diapause we see is a result of cold temperatures slowing down development and not a result of a required biological process. Some species with very slow hatch times might simply have evolved a longer egg stage that can be extended further by cold temperatures.

On the other hand, it is also possible that diapause in mantids is not managed solely by the environmental queues the ootheca experiences and that the discrepency in hatch times is also the result of diapause initiated prior to egg-laying by the environmental queues experienced by the egg-laying female. Mantids kept in captivity cannot be a very good indicator of this as we tend to keep them at more optimal food and temperature levels and lighting is just all over the place. It would be interesting to see if there is a difference in the hatch times for oothecae of the same species between ones obtained from captive bred mantids and ones obained from wild mantids near the end of the season.

That is a thought

So lets assume my cali female who was captive her whole life and went to rick at the end of august was exposed to NC climate

Now in CT in august the temps r in the 80s and daylight hours r about 14 hours

I bet they were a bit greater in NC

So basically, i dont think my cali girl had any reason to assume winter was coming

So assuming her ooths r fertile, i may see some nymphs very soon

 

[MantidLord]

That is a thought

So lets assume my cali female who was captive her whole life and went to rick at the end of august was exposed to NC climate

Now in CT in august the temps r in the 80s and daylight hours r about 14 hours

I bet they were a bit greater in NC

So basically, i dont think my cali girl had any reason to assume winter was coming

So assuming her ooths r fertile, i may see some nymphs very soon

That's a lot of assumption...and it brings a sort of nature vs nurture aspect to it. How did she adapt to living in your CT home, despite being naturally adapted to living in California?

I think the argument isn't as complex as we're making it. There are observations of wild T. sinensis ooths hatching early December because of a late frost, and the nymphs were found either stuck to the ooth frozen or dead on the ground. There were no captive conditions, simply a slight temperature change. Naturally, not all of the T. sinensis ooths in the area hatched, and those that were laid a little bit later weren't ready to hatch and when the winter finally came, they simply didn't hatch. Weather has been a huge dictator in T. sinensis. In some areas females lay only one ooth, in others they can lay two. I think the same would hold true for Stagmomantis.

 

[agent A]

That's a lot of assumption...and it brings a sort of nature vs nurture aspect to it. How did she adapt to living in your CT home, despite being naturally adapted to living in California?

I think the argument isn't as complex as we're making it. There are observations of wild T. sinensis ooths hatching early December because of a late frost, and the nymphs were found either stuck to the ooth frozen or dead on the ground. There were no captive conditions, simply a slight temperature change. Naturally, not all of the T. sinensis ooths in the area hatched, and those that were laid a little bit later weren't ready to hatch and when the winter finally came, they simply didn't hatch. Weather has been a huge dictator in T. sinensis. In some areas females lay only one ooth, in others they can lay two. I think the same would hold true for Stagmomantis.

She spent L1/2 in texas with yen

Her mother was from arizona

She grew under a heatlamp until subadult

She went to hertarems house in pasadena california for 2 weeks

Then spent a few weeks outside before goin to ricks, mating with your male, laying 2 ooths and dying

U mentioned ooths might diapause if the female laying it thinks winter was approaching

I dont think my cali female had any sense of winter coming around

My feeling is the ooths figure out for themselves whether or not to diapause

Though diapause may reassure nymphs the winter is over it has certainly been shown that most species dont need diapause to hatch

My next question

Can ooth sense how long they have diapaused for? Could someone put an ooth in the fridge for a day snd trick an ooth into thinking a whole winter went by??

 

[MantidLord]

U mentioned ooths might diapause if the female laying it thinks winter was approaching

I did? I don't feel like going back and reading, but if I did say that, I'm misspoke. I don't know anything about females sensing winter coming. The females will lay as many ooths as possible until she starves to death, dies of old age, or the cold kills her. The approaching winter doesn't change her behavior to where it affects the ooth. To suggest that would imply that maybe she injects some chemical in the ooth to keep them from hatching.

What I am saying is that the ooths figure it out for themselves (in the simplest of words) and if they don't need a cold period, and don't experience one, then they'll hatch. Read my last post, I said that most species don't need it to hatch. As for the last question, well I'm not sure. For a species that isn't dependent upon a cold period to stall hatching (say T. sinensis), probably not. It typically takes more than one day to fool an ooth. Think about it, not all winter days are cold, not all spring days are hot. So if you get one random extreme day, you don't want everything hatching because then when the weather gets normal again...things go wrong. You don't see mantids hatching on a warm day in the middle of winter. You see it after a prolonged period of warmness after winter or (in the case of those that don't need the cold) a continuing of warm weather in an unusual winter.