© Photographed October 18, 2015
Erected by Cave of the Mounds
Blue Mounds, Dane County, Wisconsin
Take a Trip Back in Time...
to Wisconsin's Oldest Classroom!
Imagine a world
where change is marked, not by days or weeks, but by centuries and millennia. This is Geologic Time, the vast boundaries by which the growth and maturity of the earth is measured.Our geologic timeline begins 540 million years ago (MYA). You would need to travel all the way to Brigham County Park -- over a mile away on our scale -- to reach 4.6 billion years ago (BYA), the estimated time that earth began! A Walk down our geologic timeline will take you on a journey to understand how earth developed -- both above and below ground.
We invite you...
to follow the footprints and discover the wonder of evolution -- from trilobites to tyrannosaurs. Take a trip through time and walk our line!
The marker is located at Cave of the Mounds and is accessible from westbound Cave of the Mounds Road, between Rooney Road (to the west) and County Highway ID (to the east), at or near
ORIGIN OF THE EARTH
4.6 billion years ago
➀ Earth was a hot and inhospitable
planet early in its history, characterized
by volcanic eruptions and frequest
meteorite impacts. No fossils are
yet known from this earliest
episode of Earth history.
You would need to travel all
the way to Brigham Park --
over a mile way on our scale
to reach 4.6 billion years ago!
3.4 billion years ago
➁ The earliest life forms for
which fossils are known are
(blue-green algae). these
algae built up mound-like
structures called stromatolites.
Stromatolites are still
around today, so cyanobacteria
might be considered the
EARLIEST SHELL FOSSILS
540 million years ago
➂ The earth is mostly a marine
environment and the Cambrian
Explosion brings the sudden appearance
pf a diverse array of marine invertebrates.
The evolution of shells and external
skeletons led to better preservation
and more abundant fossils.
the development of "hard parts"
may have been an evolutionary
response to predation.
These cool learning activities markers are next to the marker.
This path (adjacent to the parking lot) leads to the marker's location
(the marker is visible on the left, next to the boulder).
Cave of the Mounds is located in Blue Mounds, Wisconsin.