Wacky Glass Walker

This is the last of the creatures found in Calvin's fish tank, and it reminded us of Wacky Wall Walkers. This is a ciliate that uses it cilia to walk along the top of the glass. Did it evolve this trait specifically for life in a fish bowl?

A quick google search on "ciliate walking on glass" came up with hypotrich, which this appears to be. The legs with which it walks are actually bundled cilia called cirri. What did people do before google? (spend hours in the library, I guess)

Another Rotifer

Here's another rotifer from the scum in Calvin's fish tank, along with his friend the worm. The video below the picture shows the two of them in action. You can see the rotifer mouth sweeping in food, the jaws chomping it up, and the toes wagging like the tail of a happy puppy.






Why are there so many rotifers (three found so far) in this tank? I read that rotifers are added to fish tanks because they eat up debris and keep it clean. Were these added to the pet store fish tanks? Have they continued to propagate and survived the multiple tank cleanings and water changings?

Another Paramecium

Here's another creature found in the scum of Calvin's fish tank--it's quite a zoo in there. I believe this one's a paramecium based on the cilia it swims about with and the contractile vacuoles which it uses to pump out excess water. The video is taken at 100x and you can see smaller bacteria swimming around it, apparently unaware that the paramecium feeds on their kind.

Rotifer Jaws in Action

Here's another rotifer found in the scum of Calvin's fish tank (taken at 400x). At the beginning, we see the rotifer just swimming around looking for food. We then jump to a clip of it eating. You can see the cilia at the mouth moving around to sweep particles into the mouth, and then you can see the jaws chomping it up! The jaws are in the middle of the animal, and look a bit like the mouth of a sabre-tooth cat.

Brown Oozy Worm

Here's another one of Harold's friends. (Harold is Calvin's fish, and we found lots of creatures living in the scum of his tank.)

This is some kind of brown oozy worm. Is it one gigantic cell (for a microbe) or is it a multi-cellular animal? Maybe we should ask Harold.

Vacuum on a Stalk

We looked at some green and white scum in Calvin's fish tank and we found that Calvin's fish, Harold, has lots of friends.

Below is a creature that appears to be a big vacuum mouth that sucks up particles. I don't know why it contracts violently all the time. Is that how it swallows its food?



Update: This appears to be a type of rotifer. These are multicellular animals with a mouth (called a corona, which makes me thirsty), primitive jaws (called trophi) and a stomach. They also have a foot and toes, which are sometimes attached to plants, as the example above appears to be.

Update #2:  It's a Vorticella. Thanks Mr. Comments!

Chlamydomonas with Flagella

Here is one of the little guys from the Christmas Germs post below where I wondered if they moved with a flagella or cilia. Here, at 1000x, we can actually see the flagella when it's not moving.



I believe this is a Chlamydomonas protozoan because it has a red eye spot and looks like these Chlamydomas species on Wikipedia.

Pin-tip

Here's the tip of a pin at 400x. It doesn't look very sharp, does it?

Monsters of the Shallows

We found these monsters (320 um long, or about a third of a millimeter, or 1/64th of an inch) in some scum from Lake Hodges.

They are paramecia, a type of protozoa. Here they are at various levels of magnification with some body parts identified.



Here are a bunch of them swimming around at 40x. You can also see some smaller creatures swimming around, but they are just tiny dots. Watch for one at the top by the pointer get stuck trying to squeeze through an opening that's too small.



Here they are at 100x. Here you can see the regular-size critters swimming around and you can see how big these monsters really are. This is also a good magnification to see the two contractile vacuoles which expel water. If it didn't have a way to pump out water, the little guys would explode!



Here's a movie at 400x. The monster is so big, we can't even see the whole thing at once at this level. We can also start to see the cilia moving and we get a pretty good view of its mouth.



This last one is at 1000x. This is actually the first movie I took, and at first I thought it was just an air bubble. And then I realized it was moving! You get a very close-up view of the water pumps and the mouth, plus little creatures get swept away from the monster's cilia. I also thought it was interesting to see how much stuff is going on inside the paramecium--it not just a bag of molecules.

Live & Active Cultures

I was about to have some yogurt as a snack when I noticed the "Live & Active Cultures" advertising on the side. Hmmmm, I wondered, and got out the microscope. I smeared some delicious Strawberry Breyers on a slide and then ate my snack--I wasn't sure I would still want to eat it after I looked at the slide.

Once I looked in the microscope, it was anti-climatic. It wasn't until 1000x that I saw some bacteria, and even then they are quite small, as you can see below. I'm pretty sure they are Streptococci thermophilis, because of all the bacteria they put in yogurt, these are the only ones which are spherical, whereas the others are rod-shaped.


None of the bacteria in yogurt are supposed to swim, but these little diplococci (double-berries) seemed to. However, they all "swam" in the same direction and are probably just flowing on some kind of micro-stream. The microscope lens pushed on the sample and it could have created a micro-flow. Here's a short movie showing them moving:



Why are bacteria in my yogurt? When these bacteria are added to milk, they feed on the lactose and make lactic acid as a by-product (see below). The acidity then curdles the milk proteins and also gives the final product--yogurt--its characteristic tangy flavor. Anyone else hungry for some delicious Live & Active Cultures?