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Author Topic:   Winter Project
Tanypteryx
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Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(2)
Message 1 of 53 (885655)
04-21-2021 5:47 PM


At the moment I am taking a break from mowing my lawn, but on most days I am observing & photographing the development of embryos inside a clutch of 180 dragonfly eggs oviposited on Nov. 1, 2020. This is the 6th species within a group of closely related species I have worked with in this project that I started in 2017.

All eggs in the first 5 species were quite closely synchronized (within each species) in the timing of all developmental stages and hatching occurred in each group within just a couple days of each other. All the eggs were reared under the same conditions of temperature and photoperiod.

The species I am working with now is completely un-synchronized. The eggs all entered diapause (delayed development) after about 4 weeks, but then one egg recommenced development in January and hatched in early February. There was just a steady trickle of a couple a couple a day getting ready to hatch. There are still a few eggs that have not come out of diapause yet and at the same time I have nymphs that are in their 5th instar (molt). There may be between 10 and 17 instars depending on species and environmental conditions.

The species I have reared out so far can all share the same general habitat. I am trying to understand what kids of selective pressures would bake these developmental strategies into their genes.

When they hatch from their eggs they immediately shed their exoskeleton (the first molt) and become tiny little predators about 2mm long. They are partly transparent so I can see their internal structure and watch their respiratory contractions. Lots of things will eat them but they are fearless and routinely take on prey larger than themselves.

Until now, only a few species have had the development of eggs and nymphs documented, but an addition positive aspect of these projects is, for me, the development of very specialized photographic equipment and technique, to capture the details of this fascinating and complex process.

Cheers


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


Replies to this message:
 Message 2 by AZPaul3, posted 04-21-2021 6:26 PM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 3 of 53 (885661)
04-21-2021 8:21 PM
Reply to: Message 2 by AZPaul3
04-21-2021 6:26 PM


I sent you a PM.

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 2 by AZPaul3, posted 04-21-2021 6:26 PM AZPaul3 has replied

Replies to this message:
 Message 4 by AZPaul3, posted 04-21-2021 9:55 PM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(2)
Message 5 of 53 (885664)
04-21-2021 11:39 PM
Reply to: Message 4 by AZPaul3
04-21-2021 9:55 PM


You said your first batch was synchronised while the second was not.

I'm sorry, I was unclear. There were 4 prior batches or species. Each species was unique and synchronized only with itself.

The 1st Species, Aeshna palmata oviposited more than 1200 eggs on 9-Oct-2017. The eggs were kept at a constant 68F with diffused daylight. They developed for 4-5 weeks and entered diapause. The 1st embryo resumed development 1-Jan-2018 and all the eggs had resumed within a week. The sign that development has restarted is each embryo actually switches ends inside the egg in a process called katatrepsis. The embyos continued development and began hatching in about 5 weeks and were all completed in 3 days.

The 2nd and 3rd species were both oviposited on 8-Aug-2018. The 2nd species was Rhionaeschna multicolor and it gave me 750 eggs that went through very rapid development and the eggs all hatched in 16 days.

The 3rd species, Aeshna interrupta developed for 4-5 weeks and seemed to be in diapause. Diapause ended in March and the nymphs all hatched within the same week in April.

In 2019 I was not able to get any of the Aeshna/Rhionaeschna females I collected to lay eggs for me. This family, the Aeshnidae, all oviposit endophytically, that is, into vegetation or other soft material like wet floating wood. I induce oviposition by placing a female in a gallon sized container with wet unbleached coffee filter papers on the bottom. stored in a dim cool place for a day or so and the coffee filters will be riddled with eggs, that I have to very carefully under a microscope extract the eggs from the paper without getting fiber stuck all over them. Tedious work, but I can also have sets of images or videos shooting and some classic rock or an audiobook and I an in the zone.

I did get eggs from a bunch of dragonflies that were kind enough to actually drop their eggs into a vial of water if you tap the tip of their abdomen on the water surface.

In May of 2020 I got about 500 eggs from a female Rhionaeschna californica that also went through rapid development and they all hatched on day 21 and 22.

And now I am watching the 5th species, Aeshna umbrosa, that is asynchronous in development.

My hypothesis is that each species has a unique embryo development genetic program. Each of these species has a flight season that is months long so there has to be some plasticity built in depending on when the eggs are laid. Development is accelerated or delayed depending on species, but triggered by photoperiod. In other orders of insects photoperiod and temperature are the determining stimuli.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 4 by AZPaul3, posted 04-21-2021 9:55 PM AZPaul3 has replied

Replies to this message:
 Message 6 by AZPaul3, posted 04-22-2021 2:55 AM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 7 of 53 (885678)
04-22-2021 12:01 PM
Reply to: Message 6 by AZPaul3
04-22-2021 2:55 AM


So the asynchronous nature of Aeshna umbrosa is natural while the other four are all synchronous by nature. Are there major differences in environmental niche the 4 inhabit vis-a-vis Aeshna umbrosa? Seems it would have to be if the photoperiod is the determinant.
Unless ...

The microhabitat of A. umbrosa nymphs seems to be pretty much the same, and I have never seen an analysis that compares the microhabitats. Beyond 4th instar all dragonfly nymphs will prey on other nymphs if they come in range of their prehensile labium (lower lip).

The flight seasons of adults of all these species are different but some of them overlap quite a bit. They are all large strong flying insects that are habitat generalists rather than specialists. The nymphs of these species are all prey stalkers rather than lying in wait and ambushing their prey. They hunt primarily by vision but are also very sensitive to vibrations.

What of the possibility that Aeshna umbrosa was late to the evolutionary party and this asynchronous timing was advantageous due to competition?

Avoiding competition with conspecifics could certainly be a factor and with other species to a lesser extent.

Edited by Tanypteryx, : No reason given.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 6 by AZPaul3, posted 04-22-2021 2:55 AM AZPaul3 has seen this message

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Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(2)
Message 8 of 53 (886146)
05-07-2021 5:52 PM
Reply to: Message 7 by Tanypteryx
04-22-2021 12:01 PM


Dragonfly Musings
The oldest A. umbrosa nymph is now in instar 6 and there are still 3 eggs out of 180 that are in diapause and about a dozen that have completed katatrepsis and will hatch within the next 2 weeks. The asynchronous development pattern of these eggs has continued. All the eggs developed normally and entered diapause and then a couple months later 1-4 eggs per day would end diapause by going through katatrepsis, continue developing for 2 weeks and then hatch.

Every other species I have reared were quite synchronized in embryo development and hatching and that would plot against time in a steep, narrow bell curve, this includes closely related species in the same genus.

In the early 80's I reared 2 species that each took 5 years to develop from egg to adult, Cordulegaster dorsalis and Tanypteryx hageni. After 5 years I had a dozen or so surviving C. dorsalis nymphs. Several weeks before they are ready to emerge the nymphs would crawl out of the water onto twigs to explore. I placed a dry woody shrub branch in their habitat to crawl out on and got my camera all set up ready to record metamorphosis into adults. All week end I waited.... Monday morning I had to go to work at 4:00 AM, at 5:00 my wife called and said, "they are hatching!" I told her to shoot them and she got a wonderful series of shots that show all the stages of metamorphosis.

So, after 5 years they all emerged within minutes of each other. The Tanypteryx eggs were spread over 3 days but that's still incredibly tight.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 7 by Tanypteryx, posted 04-22-2021 12:01 PM Tanypteryx has taken no action

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 Message 9 by dronestar, posted 10-26-2021 4:17 PM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(4)
Message 10 of 53 (888968)
10-26-2021 9:34 PM
Reply to: Message 9 by dronestar
10-26-2021 4:17 PM


Re: Dragonfly wing movement
It's always interesting to see these kinds of demonstrations and comparisons, so thanks.

There are some high quality, high speed videos of dragonflies in flight these days that really show the patterns of movement for different kinds of flight.

Dragonflies and damselflies are unique among the insects because their flight muscles attach directly to the bases of the wing and each wing can move independently. Your diagram isn't showing normal wing movement because it shows the hindwings following the forewings. In normal flight and hovering, the forewings and hindwings move opposite each other, when the fore wings are up the hindwings are down and vice versa. The forewings create turbulence and the hindwings use those vortices for lift, speed and maneuverability. The wings can all rotate and twist around their longitudinal axis and are incredibly flexible.

All other flying insects fly by muscles attached to the walls of the thorax flexing them and moving the wings. The odonates split from the other insects shortly after flight evolved.

Now for every general rule there may be exceptions. In Costa Rica I encountered some huge damselflies, Megaloprepus caerulatus that fly with both wings synchronized, up and down together. I think this is the largest living odonate as far as body length and wingspan. There are a fairly large group of damselflies in the neo-tropics that have long abdomens for ovipositing in various kinds of treeholes that have water and mosquito larvae for prey. They are often called helicopter damselflies.

The wings of many odonates are also colored and banded or spotted with every color imaginable and are used for all sorts of display for possible mates and rivals.

Many years ago I met a fellow at a meeting from Germany named Georg Rüppell who was doing fantastic high speed filming of dragonflies in flight in the 70's and 80's and 90's. Some of his stuff may be on YouTube.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 9 by dronestar, posted 10-26-2021 4:17 PM dronestar has replied

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Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(4)
Message 14 of 53 (891675)
02-07-2022 11:13 PM
Reply to: Message 13 by dronestar
02-07-2022 3:13 PM


Re: More Dragonfly movement . . . and its sight acumen
Hey dronestar, thanks for the great video. I sent the link to my friends. We talk about these sorts of things whenever we're in the field together, and of course the rest of the time too. We're starting to make lots of video clips in the field and whenever we slow them down we can see new high speed behavior. I have shot lots of subject in flight with my still camera also and one interesting observation is that they maintain the position of their head parallel to the horizon even when their body is rotated 90 degrees in a high G turn.

So I am curious, . . . a four-propellor drone helicopter sometimes has on-board 6-axis gyro to steady it's flight. I am presuming the dragonflies high frame rate of sight also helps the dragonfly in flight, particularly when chasing (and catching) its prey. The microprocessor of a 'brain' that links its individual wings and 360 degree sight in nanoseconds is a wonder.

Humans could not pilot a quadcopter drone anywhere near the speeds and high G maneuvers that dragonflies perform. We clearly cannot process visual information that rapidly. The flight to capture prey is quite slow and mostly just short sprints because most prey probably doesn't see the dragonfly. This is also true with the dragonflies that are on the wing continuously, just a short spurt for prey.

The real high performance flight is when males are clashing with rivals or pursuing mates. They can follow their targets and track them through and against incredibly complex visual backgrounds.

And it's not just rapid 360 vision, but also broken into many more distinct bands of color as well as ultraviolet. Humans have 3 opsins to see red, blue and green, whereas dragonflies may have 30 or so opsins.

I think I am rapidly becoming a dragonfly enthusiast. Can I come with you on your next research trip? I could help carry the gear, scout photo locations, and make strawberry daiquiris when back at the research tent

I will PM you with some info you may find interesting.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 13 by dronestar, posted 02-07-2022 3:13 PM dronestar has replied

Replies to this message:
 Message 15 by dronestar, posted 02-08-2022 1:03 PM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(4)
Message 16 of 53 (891688)
02-08-2022 9:14 PM
Reply to: Message 15 by dronestar
02-08-2022 1:03 PM


Re: More Dragonfly movement . . . and its sight acumen
And as a designer, I can confidently state humans only need about . . . three, maybe four shades of oranges in life.

That's probably true about how many shades of orange we need but we can see way more than that. I remember reading about tests where subjects looked at specific wavelengths of light, but I can't remember how many angstroms the average person see the difference between. I can detect the differences between all 256 shades of each color in an 8-bit digital image as well as all 256 shades of gray. In 16bit color tones blend seamlessly. And by tone I mean brightness or darkness.

What we think dragonflies experience with the additional opsins is colors separated by wavelength, not just brightness. So we have 3 primary colors and they have 30 primary colors.

The eyes are also broken up into different zones with different diameter or aperture and different focal lengths. There is a hover fly, Syritta pipiens, the male has a group of forward looking ommatidia that only fire nerve impulses if they detect the color and flight pattern of a female which it then imitates precisely. I suspect something similar in dragonflies. They can identify males and females of their own species, but also other species based on field observations, but sometimes they make mistakes and misidentify males of other species as their own.

A book I can highly recommend about vision is, Eyes to See, the Astonishing Variety of Vision in Nature, by Michael Land.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 15 by dronestar, posted 02-08-2022 1:03 PM dronestar has replied

Replies to this message:
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 Message 21 by dronestar, posted 02-10-2022 2:35 PM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 22 of 53 (891757)
02-10-2022 2:54 PM
Reply to: Message 21 by dronestar
02-10-2022 2:35 PM


Re: More Dragonfly movement . . . and its sight acumen
While I am being silly posting about the color orange, . . .

I have a question about orange, is the word for orange the color and orange the fruit the same word in other/all languages like it is in English?


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 21 by dronestar, posted 02-10-2022 2:35 PM dronestar has replied

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Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 24 of 53 (891759)
02-10-2022 3:39 PM
Reply to: Message 21 by dronestar
02-10-2022 2:35 PM


Re: More Dragonfly movement . . . and its sight acumen
I may be compelled to buy the book you recommended sooner than later. I wish the book reviewers would have written that the illustrations inside were more polished, my best style for learning is visual.

It helped me think about vision in new ways. Another book I have learned a lot from recently is, Complex Worlds from Simpler Nervous Systems, by Frederick R. Prete, 2004. I ordered it used from Amazon for $4 and got a brand new hard cover copy.

. . . do we know what colors the dragonflies opsins detect? Are they weighted toward a particular hue? You mentioned ultra-violet. Can there be many shades of ultra-violet that multiple opsins detect? A bee is attracted to the shape of a flower's ultra-violet pattern. But I presume dragonflies do not seek out flowers for the same reason, if at all, correct?

Dragonflies having so many opsins is 'bugging' me. Nature, what the hell? Why?

I'm looking for answers to all these questions and a bunch more. We need a lot more students out there in the field making observations, especially in the tropics.

Some species of dragonflies may visit flowers to prey on insects visiting the flower for pollen or nectar, but I have not studied that behavior. It is well documented that many of the helicopter damselflies in the neotropics visit spider webs to pick insect prey from them and many other species of damsels glean insects, like aphids, from plants.

Many odonata wings have markings of all sorts of colors and patterns and some wings reflect UV patterns that are invisible to humans. I have had some truly incredible encounters with both dragonflies and damselflies in the neotropics with metallic colored wings. Damselflies in the family Polythoridae have species that mimic butterflies and that have all sorts of bright colored patterns, with lots of oranges. One species, Cora terminalis, has wings that look clear if viewed flat, but if angled just a bit the whole wing flashed bright silvery blue. It was truly amazing watching two males displaying to each other while spirally up in a sunbeam penetrating the forest canopy in Bolivia.

Or the tiny dragonfly, Zenithoptera lanei, that has metallic blue on the upper surface and shiny black on the undersides of the wings. Both sexes signal each other with various wings held down or folded closed over the back. Sometimes they even have the front wings down and the hind wings closed.

Edited by Tanypteryx, : No reason given.

Edited by Tanypteryx, : spelling

Edited by Tanypteryx, : No reason given.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


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 Message 21 by dronestar, posted 02-10-2022 2:35 PM dronestar has taken no action

Replies to this message:
 Message 25 by Theodoric, posted 02-11-2022 10:22 AM Tanypteryx has replied

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 26 of 53 (891790)
02-11-2022 10:39 AM
Reply to: Message 25 by Theodoric
02-11-2022 10:22 AM


Re: Puerto Rico
I have not worked with Caribbean dragonflies, but there are some real beauties. Any aquatic habitat should have dragonflies, but my favorite tropical habitats are mountain streams.

Dragonflies and damselflies (Odonata) from Puerto Rico: a checklist with notes on distribution and habitat


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 25 by Theodoric, posted 02-11-2022 10:22 AM Theodoric has taken no action

  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(4)
Message 27 of 53 (892141)
02-26-2022 10:22 PM


Matallic Wings in the Sun
Yesterday, after a session reprocessing some photos from a trip to Ecuador in 2013 I posted one of them on my Facebook page. It was a shot of a little tropical dragonfly, Zenithoptera lanei, that has amazing wings that look metallic blue on the dorsal (upper) surface and black or dark metallic red on the ventral surface.

The males of this species use the positioning of the wings to signal conspecific males in pretty complex displays. My photo was of a display position that we, my traveling pals, have never seen any other species perform, with the front wings held doin front of the dragonfly and the hind wings held closed over the back showing the dark underside.

This morning there was a link posted in the comments of my Facebook post to a newly published paper about the same species and proposing and testing an hypothesis for an additional function for the bright iridescent color of the wings, camouflage. The link was posted by one of the authors in Brazil.

Camouflage by counter-brightness: the blue wings ofMorpho dragonfliesZenithoptera lanei(Anisoptera:Libellulidae) match the water background free access.

This is a fascinating study, but I haven't finished reading it yet. I just got kind of excited about it because it has a bunch of interesting info about dragonfly eyesight too, and we had talked about it recently here.

I photographed and and studied Z. lanei in Ecuador in 2009 and 2013 and in Costa Rica in 2015.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


Message 28 of 53 (892364)
03-06-2022 11:54 AM


Thanks Covid
I don't know how much businesses closing because of the pandemic has affected every day life of most people, but for biologists, primarily entomologists, the closing of one business will have a huge negative impact on field research research for years.

BioQuip was the primary North American supplier of all the equipment used in the field and lab, from vials to nets, and they are closing up shop. A year ago we started hearing that they were struggling to stay afloat, and many of the people I know started placing orders and stockpiling consumables and critical equipment, but in January they announced they were closing for good. They sold the best nets and bought the best net manufacturer, so now both are gone, fuck!


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


Replies to this message:
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Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(2)
Message 30 of 53 (893932)
04-23-2022 5:53 PM


Getting Ready
I'm wasting time while I have my imaging system shooting focus stacks of dragonfly eggs (collected last September in Wisconsin) that have just come out of the refrigerator after a long winter's nap. They should recommence development (after 5 months of diapause) in the next few days. Several different clutches need to warm up to room temp before i can shoot them otherwise moisture collects on slides and coverslips etc.

This is my 44th winter rearing at least one species of dragonfly eggs that have a diapause in their normal embryonic development. The first 20 years I was using a simple compound microscope with my 35mm SLR shooting color slides of the eggs. Digital cameras and high resolving power, aberration free optics gave me unprecedented views inside living eggs and changed my life forever.


Stop Tzar Vladimir the Condemned!

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


  
Tanypteryx
Member
Posts: 3348
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 3.6


(8)
Message 31 of 53 (894190)
05-06-2022 12:43 PM


My eggs Are Hatching!!!
WooHoo! The dragonfly eggs I have been observing since last September have started hatching, on day 203 since being oviposited.
This is the 6th species in this group of closely related species that I have reared, and documented the embryo development. Watching these tiny 3mm long nymphs behavior and morphology and noting differences between these species at these earliest stages of life is fascinating, to me.
As far as I know, no one else has ever observed or documented these stages of the lives of these species.
I'm getting video too!

Stop Tzar Vladimir the Condemned!

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


  
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