The Gunflint Chert - Fossil Ecosystems of North America: A Guide to the Sites and their Extraordinary Biotas - page 3

collected samples of these from Kakabeka
Falls at Thunder Bay ( 2 ) and from the
shores of Lake Superior near Schreiber
( 3 ). When he examined thin sections of
this chert back in his laboratory, he was
amazed to find that they contained
thousands of minute spheres and
stars, with branched and unbranched
segmented filaments all less than
10 microns in size. He wondered if these
could possibly be three-dimensionally
preserved fossils, and realized that if this
were the case they would be by far the
oldest fossils then known from anywhere

on Earth. Reg Sprigg had only discovered
the 600 million year-old Ediacara fossils in
1946 (Chapter 2) and the Gunflint Chert
was more than three times as old.
Tyler immediately called in paleobo-
tanist Elso Barghoorn (1915-1984), Fisher
Professor of Natural History at Harvard
University, who confirmed that they were
ancient fossils of unicellular organisms.
The two scientists published their discovery
in Science in 1954 (Tyler and Barghoorn,
1954) describing the fossils as 'algae and
fungi' and comparing their preservation to
plants from the well-known Rhynie Chert

2

2 Kakabeka Falls, west of
Thunder Bay, Ontario. The
waterfall forms where the
Kaministiquia River flows
over the Gunflint Chert.

3

3 Flint Island, near
Schreiber, north shore of
Lake Superior, Ontario.