Biology Reference
In-Depth Information
Figure 2.17
Principal tectonic features of southern Mexico and Central America. From Don-
nelly and others 1990.
fornia. The spreading center and its northward continuation is represented
by the San Andreas fault system, which extends to about San Francisco.
The sliver of land to the west of the fault belongs to the Pacifi c plate and it
is moving northward at about 5 cm a year. At this rate Los Angeles will sub-
duct into the Aleutian Trench in another 50 million years. One result of the
movement relevant to biotic history is that the Miocene Mint Canyon fl ora,
now located in southern coastal California, has been transported 300 km
from the south; it actually represents the vegetation growing in the Sonora-
Nayarit region of Mexico in the late Tertiary.
Yucatá n
It was a dark and stormy night . . . about three years long
What minor evils might arise from the contact were points of elaborate question.
The learned spoke of slight geological disturbances, of probable alterations in
