Dino Trip 2003 - Denver Museum - Prehistoric Journey

The highlight of our visit was the Prehistoric Journey, a chronological tour of earth's history of life. Exhibits began with rocks from the precambrian and continued to the present day.

This is the entrance to the Prehistoric Journey.

20030624-1937-Prehistoric-Journey (44K)

This trilobite fossil was over 16 inches (40 cm) long! It is an early example.

20030624-1894-Trilobite (79K)

The Prehistoric Journey included a display on natural selection, using the oft-described moths of Great Britain's adaptation to soot pollution as an example. The display, however, did not describe the source of selective pressure.

This interactive computer simulation did illustrate the selective pressure quite well, however.

20030624-1898-Natural-Selection (36K)

This is the end result of a run through the simulation by Dick and Thomas. The simulation starts with 10 each fast bright and slow camouflaged moths. For each of six generations, the participants attempt to tap moths fluttering in front of two trees on a touch screen display. Tapped moths are excluded from random breeding conducted by the simulation, which results in 20 moths in the next generation. Each of the simulated generations moths have characteristics influenced by the survivors of the previous generation.

Here, after six generations, there are no bright moths surviving. The previous simulation had different results, which demonstrated the effect different predators can have on the outcome.

20030624-1899-Natural-Selection (88K)

Copyright (C) 2003 by Dick Hodgman.
If you would like a large format copy of an image, contact Dick through http://www.hodgman.org/contact/

Last modified on 2003 July 19

Valid XHTML 1.0! Valid CSS!