Tardigrade
Ecology and life history

Most tardigrades are phytophagous (plant eaters) or bacteriophagous (bacteria eaters), but some are carnivorous to the extent that they eat smaller species of tardigrades (for example, Milnesium tardigradum). In addition, a few extant species, such as Tetrakentron synaptae, alongside the undescribed Cambrian “Orsten” tardigrade, are parasitic.

Tardigrades share morphological characteristics with many species that differ largely by class. Biologists have a difficult time finding verification among tardigrade species because of this relationship. These animals are most closely related to the early evolution of arthropods. Tardigrade fossils go as far back as the Cretaceous period in North America. Tardigrades are considered cosmopolitan and can be located in regions all over the world. The eggs and cysts of tardigrades are so durable that they can be carried great distances on the feet of other animals.

Tardigrades have survived all five recognized mass extinctions due to their plethora of survival characteristics, including the ability to survive conditions that would be fatal to almost all other animals (see the next section).

The lifespan of tardigrades ranges from three to four months for some species, up to two years for other species, not counting their time in dormant states.
keywords:existence