Home
Museums
Back Issues
Membership
By R. Jay Gangewere
Carnegie Museum of Natural History scientists identify new animals,
plants and insects all over the world
Of
all the scientists, the fossil hunters may have the most fun naming new
species. Curator Mary Dawson of the museums Vertebrate Paleontology department
recalls one punster naming a new species of primitive bear-dog
Daphoenus
demilo. Say it slowly. Get it?
And curator David Berman tells of 19th-century fossil hunter
David Baldwin spending solitary years prospecting for fossils in the New
Mexican desert accompanied only by his faithful burro. An admiring colleague
named a new species after him: Baldwinonus trux. In Latin onus
means burro, and trux means trustworthy. The new species
was “Baldwins faithful donkey.”
An expert on moths, former Carnegie Museum of Natural History director
William Holland once proposed what he believed was a new genus of wild
silk moth as Carnegia mirabilis (“Amazing Carnegie”)but this 1896
name was challenged when the specimen Holland described was later identified
with a previously named specimen of the genus from 1895.
This shows there is a limit to how much fun you can have when scientifically
describing all the life forms of the world, past and present. In fact,
international commissions monitor the codes that apply to botany and zoology,
and scientists take rigorous courses in describing species and assigning
names (taxonomy). The framework for naming plants and animals is based
on the Linnean binomial system of 250 years ago, which gives a genus
name to the larger group, and species name to the members within
it. It is a system that has the strength of “dead” languages: classical
Latin and Greek. They cannot change, and they have international recognition.
“The world is a complicated place and natural history tries to bring
order to chaos,” says paleontologist Chris Beard. Like many others, he
says that Carnegie Museum of Natural History has a great 20th
century tradition in scientifically describing and classifying the forms
of life. In the currently exciting field of early mammals research, he
and Carnegie colleagues like Zhexi Luo and John Wible are at the frontiers
of knowledge with their recent discoveries of new species.
In the life sciences, scientific names describe the endangered species.
Some experts, like Peter H. Raven, director of the Missouri Botanical Garden,
predict that one-third to two-thirds of all species of plants and animals
now living on land will be extinct by 2050. Raven sees these extinction
levels rising fast because of human changes to the environment, and rivaling
in scope the major mass extinctions of past geologic history.
Scientific names must be used to describe agricultural and medical products,
or in court cases and environmental rulings. Paleontologists use scientific
names and classifications to piece together the ancient tree of life that
shows how dinosaurs evolved into birds, and primitive mammals into human
beings.
While the average person uses a common name like “tent caterpillars”
to explain which insect is eating the leaves of trees, entomologists and
botanists go beyond that. They can tell you two distinct species that have
become pests in Pennsylvania and advise on what to do about them. The “forest
tent caterpillar” (Malacosoma disstria) eats a variety of trees
including quaking aspen (Populus tremuloides) and red maple (Acer
rubrum). The “eastern tent caterpillar” (Malacosoma americanum)
feeds primarily on wild black cherry (Prunus serotina), and more
rarely on other cherries, apples and crabapples.
Today it is the “hot spots,” the biodiversity hubs, that present a pressing
need to identify new species, says curator of mammals John Wible. Areas
of Central and South America, Indonesia, Southeast Asia, and Africa, have
been poorly or infrequently sampled. New mammals are rare finds, but they
do occur. A new type of rabbit was found hanging for sale in a food market
in Laos. A small goat-like mammal was discovered in Viet Nam in 1992, and
was added to the list of some 4,600 known species of mammals. Carnegie
mammalogist Tim McCarthy and colleague Luis Albuja recently described four
new species of bats in Ecuador.
But in the worlds of insects and plantswhich together make up 80 percent
of all living thingsthe life sciences face an immediate challenge. Curator
John Rawlins of Invertebrate Zoology estimates that seven to eleven million
(some scientists speculate 40 million! ) new types of invertebrates still
need to be scientifically described. Curator Frederick Utech of Botany
estimates some 125,000 plant forms still remain to be classified and described.
Discovering a Wading Beetle
On a July evening in 1982, high up on the Sierra del Sur in Mexico,
John Rawlins saw what looked like a translucent blue spot shining beneath
the stream of water that ran over a rock face. He had set up his lights
and traps to attract a species of moth he was after, but as he waited for
the moths to come, he inspected the spot more closely. The water running
over the rock was a permanent environment, and beneath the water surface
was a glowing beetle. This beetle lived under the constant flow by letting
the water press it against the rock (it had its bubble of air to breathe
from, as beetles do). But it could also rise up on its long legs and wade
or run rapidly through the water. A good “general collector,” Rawlins took
a female specimen, which he brought back to Pittsburgh.
In 1985 this mysterious wading beetle was discussed with collection
manager Robert Davidson, and he and Rawlins returned to the site in 1986,
collecting 13 adults and larvae. After years of careful study of related
species, a new genus and species was described (Rawlinsius papillatus)
in the Annals of Carnegie Museum of Natural History (November,1998).
Davidson and museum research associate George Ball named it after Rawlins.
One unspoken rule of taxonomy is that someone else has to apply your name
to a new speciesyou cant name it after yourself. Davidson remembers that
he used to like having his own name attached to something newuntil he
discovered Hitlers name applied to a new species by a German scientist
in the World War II era, and his sense of fun diminished.
Nanotitans and Place Names
Chris Beard once described a small fossil rhinoceros by the generic
name Nanotitan (very little titan) in a scientific journal, only
to get a letter afterwards from an expert on codes in Cambridge, England.
Beard was advised that the name was previously used (or “preoccupied,”
as taxonomists say). Nanotitan had already been published in Russian,
in a Russian scientific journal in 1968, to describe a fossil cockroach
found in Kyrgyzstan, a former Soviet Republic. Beard came up with a new
name Nanotitanops (“like” a Nanotitan).
An organisms structure or place of discovery is a common way to name
or classify it. The scary-looking but harmless “Hellbender” in Western
Pennsylvania is an example. John Wiens, assistant curator of Amphibians
and Reptiles, explains that this large salamander found under rocks in
local streams and rivers is called Cryptobranchus (for its “hidden
gills”) and allegheniensius (for the “Allegheny River”).
The binomial system does not apply in the same way to archaeology. Curator
James Richardson of Anthropology says a rule of thumb in his Peruvian research
on ancient cultures is to use a geographic name, not a persons name. He
has named sites of the earliest human occupation in Peru after nearby canyons
or mountain ranges. For a hundred years, Carnegie field archaeologists
working in the Upper Ohio River region have been known for their discoveries
and descriptions of prehistoric Indian cultures. The names are usually
based on excavation sites and artifacts, such as arrowheadslike the Cresap
projectile points found at the Adena burial mound.
An Evolving Science
Any classification system designed to include all life forms is
likely to change. New hardware and software–tools and ideas–have opened
new frontiers of information. Linneaus had the magnifying lens and microscope
in the 18th centurya big advantage in tools over his predecessor
in ancient Greece, the philosopher Aristotle. Charles Darwin came up with
a theory of evolution in the 19th century that changed the way
scientists see relationships among living things. Gregor Mendel discovered
the genetic mechanisms by which one species can evolve from another. In
the 20th century scientists use new tools for DNA analysis and
computer-assisted modeling to study life forms. Only today could an ancient
flying reptile, Quetzelcoatlus northropi, get its species name from
the “Northrop” aviation corporation, which did the wind-tunnel analysis
to determine how this creature flew. Dinosaur Hall has the first complete
display of the animal in the world.
The new more rigorous world of classification demands sharper distinctions,
and the invention of subspecies and subgenera, and re-classifications.
Consider that all dogs are scientifically called Canis familiaris. This
is because dogs naturally interbreed and produce offspring–the
great test of one distinct animal species. But anyone who wants to talk
about different “breeds” of dogs has to learn a whole terminology of words
like terrier and collie invented for different types below
the species class. In botany, the species of daylilies alone has 6,000
named and registered cultivars.
People reclassify information regularly in daily life without thinking
about it. Botanist Sue Thompson teaches children about classification by
having them put all their shoes in a pile, and then sort them out by color,
size, girls versus boys, or sport versus dress shoes. Non-scientists
must deal with reclassified or reorganized items constantlyfrom the food
on supermarket shelves to the clothes in their closets.
The scientifically classified collections are a priceless resource for
21st century to use in studying the plants and animals of the
world. Each scientific name has a “type specimen”the very first example
of that organism upon which scientific knowledge of genus and species is
built. At Carnegie Museum of Natural History, in the bird collections alone,
ornithologists Clyde Todd and Ken Parkes described over 400 new species
and variants. In entomology, the current staff has described hundreds of
bugs and had 45 named after them. In Invertebrate Paleontology (which deals
with fossil life such as clams and trilobites) about 160 new species have
been named.
Natural history scientists are now identifying and classifying species
in ways far more sophisticated than did the scientists of a century agoan
era when big-game hunter Theodore Roosevelt shot so many new animals in
Africa that science awarded his name to two monkeys, a deer, a hartebeest,
an antelope, a gazelle, a Duiker, a lion, a shrew, and a rat.
Home
Museums
Back Issues
Membership
Copyright (c) 1999 CARNEGIE magazine
All rights reserved.
E-mail: carnegiemag@carnegiemuseums.org
