Heartbeat of a water-flea

[ralfwagner]

Hello,

this Alona spec. lived in a stone-pit pond:





The following video shows the heartbeat of that critter. Waterfleas do not have veins, the heart just pumps around the liquid inside the whole flea.

http://home.arcor.de/dr.ralf.wagner/Bil ... Kerpen.avi
DIVX-video, 3 MB

[Wim van Egmond]

Nice pictures Ralph!! It is a bit hard to see because of the thick carapace of the waterflea but I believe these waterfleas have a loop in the gut.

I could not see the movie, Avi's don't always work well on the Mac.

It is always a nice trick to count the heartbeat of the waterflea. Becasue I have made some educational websites I often get questions from schoolchildren about science projects (most of them want me to make their homework:) and I suggest this method. One person has a stop watch to indicate4 1 minute and the other person taps with a pensil on a piece of paper in the right beat of the heart. After a minute you can count the dots and have the beats per minute.

Wim

[Thomas Ashcraft]

Ralf wrote: " Waterfleas do not have veins, the heart just pumps around the liquid inside the whole flea. "

Hi Ralf,

Fine movie. Thanks. Water fleas seem to have good strong hearts as they last a long time time in my sample jars.

Tom

[ralfwagner]

I could not see the movie, Avi's don't always work well on the Mac.

Wim

Wim,

you must have installed the DIVX-codec to view this video. It is available for free also for Macs: http://www.divx.com/divx/mac/