Mars water ice could be simply frozen fluid of fossil tissues, bodies

Fig. 1 below shows Phoenix Mars Lander sits on soil composed of fossil
tissue.
So, the water ice claimed by scientists could be simply frozen tissue
fluid.

Fig. 1: The water ice under Phoenix is gone now, exposing bone-tissue
structure
http://www.wretch.cc/album/show.php?i=lin440315&b=20&f=1555161099&p=66

Source of above figure:
http://www.flickr.com/photos/hortonheardawho/2662452473/