Death Doubled

[billporter1456]

[billbillt]

Hi Bill P.,

Thanks for another great video.. A somber reminder of life..

BillT

[Francisco]

Nice video. Life and death in a drop of water

[billporter1456]

Thanks BillT and Francisco!

[kit1980]

Interesting video.

Why didn't you add water to stop crushing of the egg? I also think that methylcellulose (suggested many times on this forum) helps to prevent crushing by slowing evaporation and raising viscosity.

About tardigrades. I keep reading (in popular press) how tough they are, but I'm skeptical about it. Have anyone here had personal experience? I suspect a tardigrade would be crushed by a cover slip just like these rotifers.

[billporter1456]

Interesting video.

Why didn't you add water to stop crushing of the egg? I also think that methylcellulose (suggested many times on this forum) helps to prevent crushing by slowing evaporation and raising viscosity.

About tardigrades. I keep reading (in popular press) how tough they are, but I'm skeptical about it. Have anyone here had personal experience? I suspect a tardigrade would be crushed by a cover slip just like these rotifers.

I was well aware of what was happening with the cover slip. I just saw an opportunity to make a little story out of the images. When I'm scanning a slide with pond water critters, I'm looking for something unusual, potentially humorous, or that lends itself to a little fantasy, tale, or story. That's just my way of pursuing the microscopy hobby. I like tinkering with the video in my video editing program and trying to come up with captions that fit the images. I don't see a lot of others who are making the kind of videos I like, so I do it myself. What kind of microscopy videos do you prefer?

As for tardigrades, I think you miss my point. Of course they are easily crushed with a cover slip if they were crawling around on a slide. I was referring to tardigrades in their desiccated state. In that state they have survived in temperatures near absolute zero and as high as 300 F. And ionizing radiation hundreds of times a lethal dose for humans. They have survived days in outer space and 30 years frozen in ice. And these findings come from NASA research among other sources. Sounds pretty tough to me.

Thanks for watching and for taking the time to make comments.

[kit1980]

I was well aware of what was happening with the cover slip. I just saw an opportunity to make a little story out of the images. When I'm scanning a slide with pond water critters, I'm looking for something unusual, potentially humorous, or that lends itself to a little fantasy, tale, or story. That's just my way of pursuing the microscopy hobby. I like tinkering with the video in my video editing program and trying to come up with captions that fit the images. I don't see a lot of others who are making the kind of videos I like, so I do it myself. What kind of microscopy videos do you prefer?

As for tardigrades, I think you miss my point. Of course they are easily crushed with a cover slip if they were crawling around on a slide. I was referring to tardigrades in their desiccated state. In that state they have survived in temperatures near absolute zero and as high as 300 F. And ionizing radiation hundreds of times a lethal dose for humans. They have survived days in outer space and 30 years frozen in ice. And these findings come from NASA research among other sources. Sounds pretty tough to me.

Bill, I'm not critiquing you or your videos. They are very interesting, and please continue to post them! I'm just saying that you could have added more water and maybe the egg would had an opportunity to hatch, resulting in more uplifting story (but I have no idea what the expected time for a rotifer egg to hatch).

For tardigrades, I've also seen claims of extremely high pressure resistance: "more than 1,200 times atmospheric pressure" mentioned in https://en.wikipedia.org/wiki/Tardigrade. Will weight of a coverslip on a tardigrade lead to more the 1200 atmospheres? I don't know (can probably do some estimation), but I suspect the animal will be crushed.

[billporter1456]

Bill, I'm not critiquing you or your videos. They are very interesting, and please continue to post them! I'm just saying that you could have added more water and maybe the egg would had an opportunity to hatch, resulting in more uplifting story (but I have no idea what the expected time for a rotifer egg to hatch).

For tardigrades, I've also seen claims of extremely high pressure resistance: "more than 1,200 times atmospheric pressure" mentioned in https://en.wikipedia.org/wiki/Tardigrade. Will weight of a coverslip on a tardigrade lead to more the 1200 atmospheres? I don't know (can probably do some estimation), but I suspect the animal will be crushed.

You are right, I could have added water and the egg might have hatched.

As for tardigrades, it sounds like you accept the resistance to extreme temperatures, ionizing radiation, outer space vacuum, and years without water, but apparently it's the claims regarding pressure that you dispute. I don't really understand this first answer to the question of how they survive high pressure, but maybe you will: https://www.reddit.com/r/askscience/com ... grades_to/

[zzffnn]

I am guessing only:

As water bears dry out, they become very dense. However, most likely, they have to dry out and condense first, before becoming resistant to high pressure. Best way to find out is to read exactly how NASA did that pressure experiment (I have not and don't know myself - am only guessing).

Cover slip pressure is likely less than 600 atmospheres, but a wet/fresh water bear having no time/chance for internal chemical composition /physiological change likely won't survive that.

Rotifers (and probably their eggs) are likely pretty tough too, if one allows them to dry out first. I heard some worms and rotifers have survival abilities only second to water bears.

I would also vote for adding more water for a more uplifting story, though I understand it is not always possible.

[billporter1456]

I would also vote for adding more water for a more uplifting story, though I understand it is not always possible.

To be totally transparent, I had the phrase, "the fragility of life" in my mind and wanted to use it in the video. Ending the video with that phrase seemed too negative to me so I threw in the "protist cysts" and tardigrades to put a bit of a positive note toward the end. As for the pressure question, I tried to understand some stuff I read about hydrostatic pressure but I wasn't successful. For sure, the little beasts can't survive any extreme stuff without going into that dehydrated state.

[billbillt]

Hi Bill P.,

I sent you a PM..

BillT