The white granite of the Idaho Batholith near Boise, Idaho, contains dark gray xenoliths of metamorphic material. Which is older? How do you know?
A) Granite; the principle of superposition
B) Xenoliths; the principle of cross-cutting relations
C) Granite; the principle of unconformities
D) Xenoliths; the principle of inclusions
Question 2
The Mississippi River cuts through Silurian-aged dolomite between northwestern Illinois and eastern Iowa. Which is older? How do you know?
A) Dolomite;the principle of superposition
B) Mississippi; the principle of original horizontality
C) Dolomite; the principle of cross-cutting relationships
D) Mississippi; the principle of lateral continuity
Gray squirrel, London, UK
The Tasmanian devil's whiskers help them to locate prey in the dark.
Honduran White Bat
Charles Bulfinch, Harrison Gray Otis House, Boston, Massachusetts.