Ask a Scientist
On October 27, 2005, students and teachers interviewed Dr.
Niles Eldredge, a paleontologist at the American Museum of Natural History.
To learn about trilobites, what it’s like to be a paleontologist,
and what Dr. Eldredge does in his free time, read the transcript below.
|Dr. Niles Eldredge is a paleontologist at the American Museum
of Natural History.
Welcome to our Science Explorations chat with Dr. Niles Eldredge.
What exactly do Paleontologists do?
Paleontologists study fossils and that tells them the history of life
on the planet. Fossils are the remains of organisms that lived in the
past. The oldest fossils are 3.5 billion years old. They are bacteria
almost as old as the Earth itself.
We read that you used to be a mediocre science student. What
made science easier for you other than that you found an area that
made you passionate about it?
I was not actually that bad of a science student but I was more interested
in French and Latin when I was a grammar student. And music. But I fell
in love with the romance of studying ancient life by collecting fossils.
Passion is everything! If you have a flair for something and that usually
involves having a passion for it, it will be easier for you.
What makes the Galápagos so special?
The Galápagos Islands are right on the Equator and they also
have a cold water current going past them so it’s possible to
see flamingos and penguins in the same place. When Charles Darwin arrived
there in 1835, he saw that there were different species on each of the
different islands and he also realized that the tortoises were shaped
differently on the different islands. These were some of his first clues
that species were not stable but that new species could evolve from
What technology is used to find fossils?
The old-fashioned way still works best. You walk around an area where
rock is exposed and look down on the ground for telltale bits and pieces
and those are your main clues that there’s something up on the
cliff that’s just beginning to be exposed by erosion. For example,
if you see pieces of bones on the ground and then you look up the cliff
face and see where the bone fell off and if you are lucky you’ll
see the skeleton of an entire dinosaur look down at you. There are some
modern technologies of using sound waves mostly in archeology that gives
an idea of what lies below the surface. There are some remote-sensing
techniques in this digital age, but the old-fashioned way is still the
In the introduction it says you study trilobites. What are
they and why do you find them interesting?
Trilobites are extinct types of arthropods, which are a huge group of
animals that include shrimp, insects, spiders, and horseshoe crabs.
Trilobites are some of the oldest known complex animal fossils. They
first showed up 535 million years ago and became extinct 245 million
years ago in the greatest extinction of all time.
Do you think all of the fossils have been discovered?
Oh no! By no means. There are many places in the United States where
the whole hillside is full of rocks that contain millions of fossils
for example, the Catskills in New York. All of the limestone quarries
in the Midwestern United States are formed from mud and limey mud that
were deposited in ancient seas and they’ve left a very rich fossil
record. There are dinosaurs to be discovered in the Rocky Mountain States,
My son is in first grade and wants to be a paleontologist.
How can I foster his interest now?
There are many things that you can do. One obvious one is to go to your
local museum, if you have one. Now, you can also go to the museum’s
Web site and have almost the same experience. There are also books you
can read. I wrote one with my kids called The Fossil Factory that has
many activities and tells you places you can go to find fossils in your
Have you discovered any bones recently? Where is the most likely
place to find dinosaur bones?
I still go out and find trilobites all the time. I collected some just
this last summer in upstate New York. The most likely place in the United
States to find dinosaur bones is in the Rocky Mountain States like Colorado,
Utah, South Dakota, and Wyoming.
Are all paleontologists employed by museums or are they independent
Paleontologists tend to be employed by universities, museums, and oil
companies. Oil companies need experts in fossils that help decipher
the layers of rocks and help them find oil.
Do you see evidence of waste from cruise ships causing problems
for the animals in the Galápagos Islands?
Yes, I have heard about it. When I was in the Galápagos just
this last spring, an expert told me that pollution is terrible in the
ocean and on land. More people are living on the Galápagos than
ever before and fishing has started to deplete the local reserves of
fish and other ocean life.
Do you believe in evolution? How about intelligent design or
creationism? I have studied a lot about these theories and why there
is such a conflict over them. What do you think?
I think that life has evolved. There’s so much evidence for that
that it’s a fact. Life has evolved. If you look at the human fossil
record of our lineage, our ancestors living four million years ago had
brains more like those of chimpanzees than us. It’s not a theory,
it’s a fact. Intelligent Design simply says that a designer made
life the way we see it. It doesn’t tell us anything about how
we can investigate the biological world. We couldn’t understand
why some diseases become drug resistant unless we understand how evolution
What do you think about cloning? Is human cloning a good idea?
How would it affect the way that the human species evolves in the future?
Cloning is a modern technological version of selective breeding, the
way humans have been changing the characters of animals and plants like
dogs and foods. There’s no way that cloning can change the evolution
of humans because there are six billion humans on the planet and we
would need to change the genes of every person or nearly every person.
But human cloning does raise ethical questions. I’m in favor of
stem cell research but I’m not in favor of making new humans as
clones of existing people.
How are animals faring with the recent volcanic eruptions?
Have the eruptions affected your research?
Volcanic eruptions are a fact of life ever since the earth was formed.
The major volcanic eruptions like Krakatoa sent so much ash and vapor
that sunsets were colored all over the world and temperatures dropped.
When even greater eruptions occur, they can even cause mass extinctions.
Even if a local eruption kills some local animals, they’re usually
not enough to kill off entire species. So, it shouldn't be a problem
right now in the Galápagos.
How do you feel when you look at fossils?
Fossils thrill me. Trilobites have eyes and sometimes I think they’re
looking at me.
What other kinds of animals live in the Galápagos besides
Iguanas; many kinds of birds, the famous Darwin Finches that have 13
species some with big beaks to crush big seeds and others with tiny
beaks and the Woodpecker Finch that uses twigs to get insects from
inside tree bark. There’re many species of seabirds like the Laysan
Albatross and the Blue-Footed and the Red-Footed Boobies; the Galápagos
Hawk; and the Flightless Cormorant, which has small wings and cannot
fly. There are no bigger animals except for goats, pigs, and dogs that
humans have brought in that’ve caused problems for the other animals.
I think there’s a non-poisonous, native Galápagos snake.
How long does it take for a dinosaur bone to get from the dig
site to the museum?
It depends on many things. Many dinosaurs are known to be in the ground
in the Western United States but have not been dug up because it costs
millions of dollars to excavate a dinosaur. But for unusual or rare
types of dinosaurs, people hurry up and try to excavate in one or two
summer seasons. They wrap the bones in plaster to keep them safe, haul
them out in trucks, and get to the lab in the museum as fast as they
can. Then it takes much longer to put them on display. Most fossils
don’t go on display but stay in the research collections because
we have many more fossils than we can put on display and these fossils
are collected for scientific study.
Who influenced you growing up? Did you have a favorite teacher?
I enjoyed many of my teachers. I had a favorite English teacher in high
school, but I liked school, so I liked many of my teachers. I was influenced
by my parents. When I got to college, I kept my eyes open and tried
many fields like Latin and Anthropology. But there was one faculty member
at Columbia, Marvin Harris, who was a famous anthropologist and influenced
What do you think happened to the dinosaurs?
I agree with most scientists that there was a mass extinction 65 million
years ago caused by an extraterrestrial body probably a comet, maybe
an asteroid – [colliding] with the Earth. The explosion would’ve
sent a tremendous amount of ash, dust, and water vapor into the upper
atmosphere, dimming sunlight on Earth and reducing photosynthesis in
plants. Plants are the base of the food chain on both land and in the
sea. Once the plants went, then plant-eating animals would have nothing
to eat and [soon neither would] the animals that eat the plant eaters
like Tyrannosaurus eating Triceratops. So, the dinosaurs became extinct
but some animals, like birds, managed to get enough to eat and survive.
What if someone's land has a bed of fossils and they do not
want to give permission for digging? Would anyone be able to override
their decision for the scientific finds?
That is an interesting question, I think the basic answer is no because
we have respect for property rights. If the fossil is found on government
lands, permits can be obtained for the excavation, but private property
is private property.
Are there many job openings in the field of paleontology and
what is the income range?
People should follow their passions to become paleontologists. All my
students have managed to find jobs. The salary range is like a normal
university range, like $40,000 a year for an assistant professor to
$140,000 for older professors.
Do you think humans are on their way to evolving into something
else? Into what?
Humans have evolved, but most species if they are successful don’t
change much once they’ve evolved. New species come when an existing
group of animals become isolated from the rest of the animals in the
species. Because there are six billion humans on the planet, isolation
to form a new species is very unlikely.
What discovery made you well-known?
I worked on trilobites my whole career and the trilobites led me to
the idea of “punctuated equilibria.” I’m better known
for that idea than any particular fossil that I discovered. “Punctuated
equilibria” is the idea that species don’t change much
sometimes not for millions of years and when evolution happens, it
happens relatively rapidly as populations are isolated and new species
If you could nominate a national fossil what would it be?
(Laughs) I know most kids would pick Tyrannosaurus Rex, but I would
pick Phacopus rana, the frog trilobite that led me to my ideas about
“punctuated equilibria.” Phacopus trilobites are found in
many states of the U.S., so they’re truly a national trilobite.
What do you do in your free time?
I love to play trumpet and coronet mostly jazz and I collect old
coronets as a hobby. I also love to play with my grandchildren.
What is the most common evidence you use to infer about the
previous life of a fossil?
It depends. If it’s a trilobite, I look at the eyes to get a sense
of how the trilobite was able to walk using its eyesight. If the eyes
point down, you know they’re a swimmer. If they look ahead, you
know that they walk. And if they’re blind, you know that they
swam in water that was so deep that sunlight didn’t reach the
Does the Museum really get things to identify like the shell
in a crate in the “Solve the Mystery” activity?
Yes, all the time. People bring fossils in and they want to identify
them. Sometimes if the fossil is rare, they’ll donate it to the
museum and the scientists will study it and publish an article about
it. I’ve done that myself. It was a horseshoe crab from Bolivia.
What special skills do paleontologists need?
I would say passion for living things and a desire to bring dead things
back to life by understanding fossils as living creatures; also, the
ability to travel and collect fossils though if you can’t travel,
you can also work in the lab and a deep knowledge of biology and
What would you like to study next?
I’ve been working on Charles Darwin for the last two years and
how he came to his ideas. Now, I’m interested in how man-made
objects like musical instruments, watches, cars, computers, etc. have
changed through time.
What's the most interesting fossil you've ever found?
The most interesting fossil I ever found was actually brought to me
by an amateur collector from Bolivia. It was a fossil horseshoe crab.
It was very rare and it showed that 400 million years ago horseshoe
crabs had flexible parts in their bodies and not the single shield they
Thank you so much for your interesting questions and I hope some of
you go on to become paleontologists some day.