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Dr. Guy Narbonne
 | 1) The Origin and Early Evolution of Animals
Image: Swartpuntia germsi, fossil and a reconstruction
of the youngest Ediacaran fossils from a recent find in Namibia. |
The Ediacara biota (575 - 543 million years old) is a Late Precambrian assemblage
of soft-bodied organisms that represent the oldest animals in Earth history.
Some species show familar patterns and appear to represent the rootstock from
which modern metazoans evolved, others are difficult to classify with any living
animal groups and may represent a "failed experiment" in the evolution of life.
Ediacaran communities were the first animal ecosystems on Earth, and studies of
their interactions with their environment and each other can shed light on the
origin of ecosystems. To learn more about these fossils, please visit our on-line
exhibit The Dawn of
Animal Life, which
includes updates on our recent research on
The Mistaken Point assemblage and
The Oldest Complex Animals. A recent article "Fossil bonanza at Newfoundland's
Mistaken Point" in the January-February 2004 issue of Canadian Geographic also
provides an excellent description and spectacular photographs of our work in Newfoundland.
Our studies in NW Canada, southern Africa, and Newfoundland over the past two
decades resulted in numerous publications and several graduate thesis. Recent
investigations have increasingly focused on the Mistaken Point biota of eastern Newfoundland
(575-560 Ma), which represents the oldest Ediacaran fossils known anywhere, in
fact the oldest large and architecturally complex organisms in Earth history.
These Ediacaran fossils are preserved on more than 100 large bedding surfaces
spanning nearly 4 km of section, each surface littered with tens to thousands
of fossil specimens that died in place when they were smothered beneath beds
of volcanic ash. This provides a superb natural laboratory for our studies
of the affinities, evolution, and ecology of early animals and their ecosystems.
Two M.Sc. theses on the sedimentology and community ecology of Mistaken Point
were recently completed, a Ph.D. thesis on the frond-like fossils is in progress, and other thesis projects are available.
Click Here for a list of recent theses,
projects, and publications.
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2) Proterozoic-Cambrian Carbonates and ReefsImage: Precambrian pinnacle reef 300 meters (1000 feet) high
surrounded by bouldery talus. From the Little Dal Group (ca. 850 million years
old) in the Mackenzie Mtns., Northwest Territories, Canada. |
Northern Canada contains some of the best preserved examples of Proterozoic
reefs and other carbonates anywhere in the world, and Dr. Noel James and I
collaborate in studies of these structures. Our studies show that, although
these stromatolite reefs lack skeletons of any sort, they were remarkably
similar to modern reefs in their growth style and in their response to changes
in sea-level. Our microscopic analyses have extended the range of reef-building
calcimicrobes, the major microbial constructors of Paleozoic reefs, back nearly
250 million years into the Proterozoic. These features imply that the origins
of Phanerozoic reef ecosystem were in the Precambrian. Graduate.theses
on an 850 million year old reef complex in the western N.W.T. and
on a 1200 million year old barrier reef on the north coast of Baffin Island
were recently completed and opportunities are available for studies of other Proterozoic
reefs in northern Canada.
We are also interested in non-actualistic sedimentation - how have carbonate
sediments responded to the evolution of the Earth and life throughout the
Precambrian and Phanerozoic? Recent papers have discussed molar-tooth carbonates
(a strange rock-type that characterized a billion years of the Proterozoic but
that is no longer forming anywhere on Earth) and the sedimentary/biological/chemical
response to the global glaciations that characterized the middle part of the
Neoproterozoic (commonly referred to as the "Snowball Earth"). Several projects
are in progress and other opportunities are available.
Click Here for a list of recent theses, projects,
and publications.
 Back to Dr Narbonne's Home Page
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This page, and all contents (except as noted), are Copyright ©: 2003 by Queen's
University, Kingston, Ontario, Canada.
Last Revision: 9 February 2004
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