Water bears (tardigrades, the Latin term "tardigrada" meaning "slow walkers")
are extremely strange microscopic animals. Though almost completely unknown
to humans - just have a try and ask your neighbour -, they can be found
virtually everywhere:
on the ground of the oceans, under massive layers of ice, on top of the
Himalayas, in hot fountains, on meadows, in forests
and - you can bet on it - close to you, no matter where you live.
A small droplet of water is an apartment, possibly even a universe for a water
bear. Water bears - a first visual impression (real size of this animal ca. 0.3 mm)When the "apartment" water droplet evaporates, tardigrades are
able to form extremely durable dry states, so-called tuns. Even after many years
small traces of water are sufficient to convert those dry tuns back into living
animals, within a few minutes. This is the reason why one of the most prominent
water bear species, macrobiotus hufelandi was named
after the famous surgeon Hufeland who had published about the art of prolonging life. Goeze's water bear portrait (1773)The small video clip below shows the enormous grace and muscle control
of the water bears. Overall they have eight (!) legs, but under the microscope
you will perceive a lower number at the first glance because some of the legs
are hidden behind the baroque body.
When looking closer you will see also claws, eyes, mouth, stomach ... |
video tag html5 by EasyHtml5Video.com v3.5 |
Tardigrades are a fascinating subject, also for
educational purposes, not only for the biological education at school level but
also for grown-up people. Water bears can be When looking closer the tardigrades reveal more and more marvels. The image below represents a tardigrade egg, only one of many many different species. There are eggs with a fascinating polygone structure, with high levels of symmetry and sophistication. In the final stage of development the eggs are becoming more and more transparent so you can follow the growth and increasing life activity in the eggs under your microscope. Below you will find an image of an egg of the water bear Macrobiotus richtersi : Tardigrade egg. Real size about 0.08 mmIn issue no. 2 we will unveal the most promising types of localities where
you can expect to find water bears and explain the procedure how
to study them without being a water bear killer. Water bears need a spaceholder
between the object slide and the cover glass, so take care not to exert undue
pressure on their bodies. © Text, images, and video clips by
Martin Mach (webmaster@baertierchen.de).
|