http://en.wikipedia.org/wiki/File:Hazard_O.svg
http://en.wikipedia.org/wiki/File:Hazard_T.svg
http://en.wikipedia.org/wiki/File:High_voltage_warning.svg. Public
ancestor
of all living organisms.
5
(Source: http://en.wikipedia.org/wiki/Image:Phylogenetic_tree.svg, License: Public Domain)
Each of the following life
http://upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Brosen_windrose.svg/600pxBrosen_windrose.svg.png, License: GNU Free Documentation)
A compass needle aligns