MicrobeHunter.com Microscopy Forum

It only rains here about 20cm in any given year, often less. Recently, though, it's rained more than usual here in the high desert and when then that happens things green up dramatically, the rocks get wet, and some of those divots and depressions fill with water. Not expecting to see much of anything, I sampled the water thinking that I'd see maybe a few algaes and a larva or two. Boy was I surprised. Rock pools are sometimes called "potholes"; they're bowl-shaped depressions in the rock that fill with water when it rains, then quickly dry up afterwards. Exposed water doesn't last very long around here, so I pretty had to keep my eye out on where in the hills it had recently dumped, then run in, find me a rock pool, and grab a sample. I kept it simple: One sample of the water itself, one sample of the crud on the edges, and a sample just below the sediment layer in the middle of the pool. Almost nothing is known about the biology of such rock pools and the questions these things raise in terms of evolutionary biology are also pretty fascinating. Interested? Here a short video:

Excellent video - thanks for the skill and time to make it.

Very nice!!

Lovely clear images with no mention of the hours of cleaning glass.

A beautiful presentation ! of the scenery and sample.

Questions:
1. Details of microscope, camera etc ?
2. The inside of most or all of the rotifers includes a bright red corpuscle. Was it fluorescence (combined with DF) ? the leaky crushed rotifer was devoid of that red stain.
3. Were the green circles micro algae ?

Hobbyst46 wrote: ↑

Mon May 29, 2023 8:19 am

A beautiful presentation ! of the scenery and sample.

Questions:
1. Details of microscope, camera etc ?
2. The inside of most or all of the rotifers includes a bright red corpuscle. Was it fluorescence (combined with DF) ? the leaky crushed rotifer was devoid of that red stain.
3. Were the green circles micro algae ?

Yes, it is pretty... darkfield well slide observation is visually cool and quickly becoming a favorite, though I'm not a fan of the post-processing work that goes into making a video. Here's a few answers to your questions:

1. Nikon Optiphot w/ direct projection to a Sony Nex5 camera, processed in DaVinci Resolve.
2. No fluorescence dyes were used and I do not know what that red stuff is though I've seen it elsewhere in the internets. Interestingly, I can see these rotifers in my water sample and they have a rust-red color. When I take it out of the fridge, there's a rust colored sludge at the bottom that gets redistributed as the water warms up. Yes, that leaking rotifer has no red goo coming out of it and, again, it's a total mystery to me.
3. My guess is that those green circles are algaes of some kind but that's according to the few papers I've read on the topic with few actual photos to reference. Rock pools are home to many species of cyanobacteria; probably shouldn't surprise me if that's what they are.

Sure Squintsalot wrote: ↑

Wed May 31, 2023 6:56 pm

...2. No fluorescence dyes were used and I do not know what that red stuff is though I've seen it elsewhere in the internets. Interestingly, I can see these rotifers in my water sample and they have a rust-red color. When I take it out of the fridge, there's a rust colored sludge at the bottom that gets redistributed as the water warms up. Yes, that leaking rotifer has no red goo coming out of it and, again, it's a total mystery to me....

Thanks. I did not mean to suggest that the dyes were used. Rather I thought of natural fluorescence - chlorophyll maybe ? Does the rotifer consume algae ?

I missed this one!

This is an amazing and very complete register. Thanks for sharing!

Back in the foothills for a hike when I ran across this dried up rock pool:
Adding to the fact that I'll never look at these things the same way again, I was struck by how much sediment had collected at the bottom. This is a pretty sheltered location that doesn't see a lot of wind kicking up sand and dirt. This would mean that most of that sediment is the result of chemical weathering of the granite occurring when the pool is wet, specifically, as it's drying out. It also looks like something rather large is actually living in that sediment. I bet it probably tastes pretty good with all that rotifer jerky and sun-dried cyanobacterial salad
My goal this summer will be to find that rock pool exposed to the most hellish conditions, collect the containing sediment, rehydrate it, and see what turns up.

Should be fun!!

Granite itself, when eroded and disintegrated by the elements, forms beautiful and rich sand, where the three main components - quartz, feldspar and mica - are separated. Fun looking with and without polarized light.

Sure Squintsalot wrote: ↑

Thu Jun 01, 2023 5:02 am

My goal this summer will be to find that rock pool exposed to the most hellish conditions, collect the containing sediment, rehydrate it, and see what turns up.

Should be fun!!

Ok...it was decidely NOT fun.
It took about 4 hours in two tries in 100­­­­ degrees afternoons to even find this thing.
Some pretty cool surprises in here!

Sure Squintsalot wrote: ↑

Sat Jul 22, 2023 3:16 pm

Ok...it was decidedly NOT fun.

Thanks, that was very enjoyable.

Excellent.

Thank you for this microscopy field project, 'sure squint'...very enchanting and so relevant to harsh changes in our biomes now upon us.

I really was drawn along with you questions which emerge as we observe the habitats microscopy. Wonderful microscopy sharing .

That terrain is harsh! But I wish I could take my refractor telescope to that area for a weekend of dark skies. all the best, charlie g

charlie g wrote: ↑

Fri Jul 28, 2023 9:26 pm

That terrain is harsh! But I wish I could take my refractor telescope to that area for a weekend of dark skies. all the best, charlie g

I sold my 4.5in reflector because I was so frustrated at waiting for good seeing. The air here is dry and clear but there are many nights with weird temperature layers and high winds. It all makes for surprisingly few nights of good viewing!

Great study and very appropriate music. Thanks !

Just watched this. Really great presentation and imaging.

Really nice done. Thanks for taking them time to create and share this.

Glad people enjoyed this movie.

I've learned that the difficulty in making these things is taking the time to do a little research, which often ends up in dozens of hours spent finding, reading, and learning about this amazing stuff.

I just came across this. Amazingly nice work! Thank you!