Tardigrade (microscopic)
The tardigrade was a docile micro-animal that lived in the waters of Earth.  It was capable of surviving both extreme  and sub-freezing temperatures. The tardigrade was able to incorporate foreign DNA in its genome through horizontal gene transfer. ()

When Michael Burnham was a little girl still living with her biological parents, she slept with a stuffed animal resembling a tardigrade. ()

The organism nicknamed "Ripper" shared some natural traits with the tardigrade, and was described as its cousin. Because of this, that species was informally also called a . (; )

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Earth animals