[sopchi]

OK, I see. I still find that surprising because I would imagine having the pipette hanging from your mouth doesn't allow ou to really see what is going on if you are really trying to hit a target volume. I would have thought the feedback you need is visual.

[dekhn]

Oh. I'm actually looking at the pipette tip under a microscope (in my case it's clear glass that I pulled to a fine tip using heat) and I can see the tardigrade get sucked into the tip when I gently pull with my mouth. And then I can see it whoosh back out when I push. The actual volume doesn't matter, just that I pick a single tardigrade and place it where it needs to go.

The other folks pipetting by mouth are actually looking down at the tube and see the fluid volume reaches a particular well-defined line on the glass pipette. If you can taste the fluid, you've gone too far.

[function_seven]

I just looked up photos of people pipetting by mouth. They use tubes.