Our First Animal

We looked at the green scum in Calvin's jar and found nematode worms--our first multicellular animal! These movies were taken at 1000x with our oil immersion lens (there's a drop of oil between the lens and the slide to minimize optical distortion).

In this first clip, you can see the worm swimming through the water sucking up food particles. There are also other creatures that swim around, including the battle-ships seen previously. I'm now convinced they are swimming under their own power.



In the second clip, we trace the full length of the worm, from the head to the tail (at least I think it's a tail since I didn't see food particles going into it). It is 300 times longer than it is wide. If Calvin were that long, he'd be 230 feet tall! During this sequence, it's moving backwards--I wonder why.



The next clip shows our friend the nematode get stuck in some junk on the slide (I think it's from where I smeared the green scum on the glass). It's body doesn't seem to know that the tail is stuck and it just keeps pushing until the tail, just before seeming to break, springs around and frees itself.



In the last clip, our little fellow starts going forward again so we follow the nematode back to the head, where it runs into another nematode which isn't moving. Not only is there a battleship creature swimming nearby, several clear, quick-swimming creatures swim through the frame. One even gets stuck between the two nematodes, discovers its predicament, backs out, turns around and swims away. They seem to be smarter than the nematodes.



Who knew green scum was so interesting.