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A: Paleontology is the study of fossils. A fossil is
defined as any trace of a past life form. Thus, although wood,
bones, and shells are the most common fossils, under certain
conditions soft tissues, tracks and trails, and even coprolites
(fossil feces) may be preserved as fossils. Although most of
the fossils that paleontologists study are several thousands
to several billions of years old, there is no absolute minimum
age for a biological structure to be a fossil.
Paleontologists study these fossils and attempt to use them
to reconstruct the history of the Earth and the life on it.
Some study the ecology of the past; others work on the evolution
of fossil taxa. Click here to find
out more about paleontology.
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Q: How does paleontology differ
from archaeology and anthropology?
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A: Archaeologists primarily work with human artifacts
-- objects that have been made by humans -- and with human remains.
Anthropologists work with humans -- their cultures, societies,
languages, and ways of life, in addition to their bones and
artifacts. Some paleontologists do study the fossil record of
humans and their relatives. However, paleontology as a whole
encompasses all life, from bacteria to whales. Paleontology
does not usually deal with artifacts made by humans.
However, archaeologists and paleontologists might work together.
For instance, a paleontologist might identify fossil animal
bones or plant pollen associated with an archaeological site,
to find out what the people who lived there ate; or a paleontologist
might be called on to analyze the climate at the time a particular
archaeological site was inhabited.
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Q: What are the practical uses of
paleontology?
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A: First of all, a number of natural resources are in
fact fossils, or derived from fossils. Coal, oil, and peat are
derived from fossil plant material; marble is metamorphosed
limestone, which is often biogenically deposited; diatomaceous
earth (used as an abrasive and in gardening) is made up of fossil
microscopic siliceous skeletons of certain algae. To study these
resources -- and to identify areas and rock layers that are
likely to contain them -- requires in-depth knowledge of sedimentary
rocks and of the fossils contained in them. Some paleontologists
work for the petroleum industry, and use fossils to interpret
sequences of sedimentary rocks.
Paleontologists who work on relatively recent fossils have
developed approaches to reconstructing past climates and environments.
Today, environmental change, global warming, and so on are household
words. Paleontologists can provide historical data on past climates
and apply it towards understanding future trends and their likely
effects. If we understand the effects of climate change, for
instance, on our world in the past, we can understand its probable
effects in the future.
Finally, paleontology is an increasingly important component
of historical biology. The life around us today has been shaped
through its long history, and understanding its past is important
to understanding its present situation. There are a number of
techniques and fields that deal with reconstructing the past,
but paleontology provides hard data on past events. Paleontology
can potentially provide much data on the evolutionary relationships
of organisms, which in turn gives a deeper understanding of
biodiversity.
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Q: How do paleontologists know how old
their fossils are?
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A: A complete answer to this question would require
a book-length exhibit (we are planning an exhibit to answer
this question in more detail). Briefly, paleontologists deal
with two types of dating, absolute and relative. Absolute dating,
which estimates the age of a rock or fossil in years, is most
usually done by measuring the amounts of a radioactive isotope
and its decay product; since isotope decay rates are known to
be constant, the age can be calculated from the relative amounts
of parent isotope to daughter product. Fossils up to about 40,000
years old can be dated using carbon-14 if there is enough organic
matter present. Older rocks can be dated using potassium-40,
which decays to argon-40, or uranium-235, which decays to lead-207.
However, many sedimentary rocks cannot be dated directly by
these methods; dates usually are obtained from igneous rocks
within a sedimentary sequence, such as lava flows or ash beds.
Such dates are maximum age estimates for fossils above the dated
beds, or minimum estimates for fossils below the beds.
Relative dating has been practiced for nearly 200 years, arising
from the observation that different layers of sedimentary rock
contain different fossils, and that this sequence can be recognized
in other rocks at other localities, even those far away. This
allows fossil-bearing rocks to be dated relatively; on the basis
of its fossils a rock might be placed in, say, the Ordovician,
which came after the Cambrian and was followed by the Silurian. This technique does not depend
on knowing the actual numerical ages of the rocks. Not all fossils
are equally useful for relative dating, or correlation; some
are rare, restricted to small geographic areas or to particular
environments, difficult to recognize, or have such long ranges
as to make precise correlation impossible. Fossils that are
the most useful for correlation tend to be widespread, found
in many rock types, easily recognizable, and short-lived enough
to permit precise placement in the geologic column.
Learn more about carbon-14 dating! The 14C
WEB-Info site, at the University of Waikato, New Zealand,
provides extensive information on this important absolute dating
method.
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Q: Did humans and dinosaurs ever live
together?
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A: No.
The Flintstones and Alley Oop notwithstanding,
the last of the dinosaurs -- with the exception of the
birds, which are dinosaur descendants -- died about 65 million
years ago. There is no reputable evidence of human life at the
time, or at any time until about 2.5 million years ago, the
age of the oldest known fossils in the genus Homo.
There have been periodic claims of human footprints, teeth,
etc. being found together with dinosaur tracks or other fossils.
None of this fossil evidence is credible; all cases of "human
remains" from the time of the dinosaurs have been investigated
and found to be either forgeries or misidentifications. For
more detailed information, visit 'The
Texas Dinosaur/"Man Track" Controversy'.
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Q: What training is needed to become
a paleontologist?
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A: Paleontology is actually one of the few fields of
science left in which amateurs can and frequently do make important
contributions. Formal education is not a prerequisite for becoming
a paleontologist. What's needed is a keen analytical mind, curiosity
and imagination tempered by scientific rigor, and lots of patience
-- to keep visiting sites, to keep good notes, and to familiarize
yourself with what is known about the fossils and time period
that you are studying.
Formal education, however, is generally necessary if you want
employment. Museum preparators and industrial paleontologists
may need only a master's degree; the doctorate is necessary
for most academic paleontologists. Few universities offer degree
programs in paleontology itself. Most universities that offer
paleontology coursework do so through their geology departments
(UC-Berkeley is an exception). However, a thorough grounding
in evolution, ecology, and/or systematics is increasingly necessary
for paleontologists.
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Q: How can I find fossils in my area?
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A:
- Start looking! Quarries, roadcuts, and cliffs are good places
to start; just remember to get permission when necessary,
and to take appropriate safety precautions (for instance,
if you find a fossil 50 meters up a sheer cliff that is prone
to rockfalls, leave it alone).
- Contact your state's, province's, or country's office of
geology, geological survey, department of the environment,
or equivalent. In the US, many state geological offices sell
various maps and publications on all aspects of the state's
geology, including paleontology. The United
States Geological Survey also puts out an immense number
of publications, including reports on the paleontology of
various areas; analogous government offices exist in other
countries. These publications can also be found in many university
and well-stocked public libraries.
- For some regions, there may be published guidebooks available.
These may be useful both for finding sites and identifying
the fossils found there. If your local library or bookstore
doesn't have them, try the bookstore of a natural history
museum, or a natural history book dealer.
- Amateur paleontology organizations often keep locality
lists and sponsor expeditions. Check to see if there is one
in your area or in the area you plan to visit; this
site lists a number of organizations. If the organization
publishes a newsletter, that can be extremely useful.
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Q: What equipment is needed to collect
fossils?
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A: It all depends on where you're going and what you
plan to collect. Some fossils may be effortlessly picked up
from the ground; others require dynamite or jackhammers to be
extracted (not recommended for the amateur!) Many paleontologists
carry a geologist's hammer or masonry hammer; rock slabs may
be split with this hammer, with this hammer and a cold chisel,
or with a stiff-bladed putty knife, depending on their hardness.
In locations where the sediment is soft, a trowel may be more
useful; soft sediment may be screened for fossils by being sifted
through a screen of appropriate size. Soft-bristled paint brushes
are useful for brushing dirt from your finds. When working in
hard rock areas, eye protection is a very good idea. Hard hats
and steel-tipped shoes may also be called for at certain sites;
at some working quarries, you are required to wear these. A
hand lens is quite useful for examining specimens in the field.
And never go into the field without a notebook and pen or pencil,
for writing down the location and local geology. Of course,
if you're going to be working in a remote area, you should pack
water, food, first aid, maps, sunscreen, and so on.
Most invertebrate fossils may be wrapped in paper or placed
in bags for transport; delicate fossils may require more care.
Large vertebrate fossils may require special techniques and
teams of people to get them out of the ground without damage
or destruction. If you should find a large vertebrate fossil,
we urge you to leave it where it is and make an accurate report
of its location to the nearest natural history museum or university
department.
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| Q: What regulations govern fossil collecting? |
A: Rules and laws governing fossil collecting vary from
region to region. It is your business to find these out. In
general: if you collect on private land, get permission from
the owner. You will need a permit to collect on land managed
by the BLM (Bureau of Land Management) in the United States,
or in national parks. In the United States, most roadcuts are
public domain and may be freely collected; however, roadcuts
that are unsafe, or that have been defaced, may be closed to
collectors. Wherever you collect, the unwritten rules of ethics
require that you not deface sites or "clean them out" of fossils,
that you not litter, and that you not endanger yourself or others
by irresponsible actions (e.g. excavating into a high, crumbling
cliff). If you find something genuinely rare or worthy of study,
consider depositing it in an appropriate museum, where it can
be kept for reference and study for generations to come.
Take a moment to peruse the Paleontological
Society Code of Fossil Collecting.
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Q: What should I do with fossils that
I pick up?
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A: The scientific value of a fossil is largely dependent
on the quality of its associated locality and geological data.
Keep notes, as accurately as you can, on the location where
you found the fossil - paleontologists in the USA typically
use the topographic maps published by the US Geological Survey,
which are available from the Survey or from many libraries,
and which permit the pinpointing of a locality. Also take notes
on the local geology - on the type of rock in which the fossil
was found, and on the other rock layers above and below it,
if they can be seen. Sketches and photographs are helpful here.
Some fossils may need preparation to be seen to best advantage.
Again, the type of preparation needed depends on the nature
of the material. Soft sediment may be cleaned from fossils using
paint brushes, warm water, or small picks. Fossils in harder
rock may be exposed by careful work with needles or with a micro-sandblaster
(expensive). Broken fossils may be repaired; some collectors
swear by Elmer's Glue. Vertebrate bones are often covered with
acrylic; crumbling bones may need specialized techniques such
as vacuum impregnation. This, and other techniques such as acid
baths, are probably best left to the pros.
For more information, the book Handbook of Fossil Preparation
Techniques, edited by Bernhard Kummel and David Raup, is
the best resource on how to prepare fossils (it may be hard
to get).
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Q: What organizations exist for paleontologists?
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A: The Paleontological
Society is the primary North American society of paleontologists.
It publishes the journals Paleobiology and Journal
of Paleontology, and a newsletter, Priscum.
Although geared towards professionals, the Paleontological Society
also includes amateur members.
The Palaeontological Association
is the primary paleontological society based in Britain; it
publishes the journal Palaeontology and the Palaeontology
Newsletter. Paleontologists may also join the Geological
Society of America, the Society
of Vertebrate Paleontology, and/or a number of other societies.
All of these socities have an international membership.
There are many other professional societies and fossil clubs
in the United States and elsewhere. We can't list all of them
here; check this
list of societies and clubs in the United States. Some organizations
are affiliated with museums or university departments; inquiries
here can point you in the right direction.
You might also consider becoming a Friend
of the UC Museum of Paleontology.
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Q: What are some other on-line sources
for paleontology?
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A: Here are a few to get you started (and hats off to
Kent Noble for helping us find some of these)
General:
E-mail Mailing Lists:
Online
Resources for Earth Scientists has a comprehensive list
of mailing lists, with information on how to subscribe.
Newsgroups:
Note that your browser must be configured for the newserver
on your system for you to be able to use the newsgroups themselves.
However, several newsgroups maintain FAQs, archives, and sometimes
more data on the WWW: these resources are accessible even if
you cannot access the newsgroups themselves.
Vertebrates:
Paleobotany and Micropaleontology:
Several of these sites contain extensive lists of more links
of interest to paleontologists. Or if none of these satisfy
you, go out and put your own collection on-line, like this
person did!
We've scattered yet more links to biological and paleontological
sites throughout our exhibits.
Or you may take our subway
for much more extensive listings of museums and on-line resources
in a wide variety of fields.
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