Species Experts Are Nearing Extinction

William Mullen
Chicago Tribune

January 16, 2002

Even as public concern grows over the accelerating extinction of species, the scientists who traverse the globe to collect, identify, and enumerate the world's plants and animals also have been disappearing at an alarming rate.

They are called taxonomists, and in the last 20 years their field has been crushed like a hapless bug wandering into the path of speeding technology.

Almost all research funding and prestige have shifted to biologists, who use electron microscopes and DNA sequencing to study life processes on a molecular and genetic level.

As a result, the taxonomists who remain fear that their branch of science is disintegrating—with grave implications for the conservation and ecology movements.

"The scholars we rely on to keep track of biodiversity are becoming extinct," said Petra Sierwald, a spider taxonomist and curator of insects at the Field Museum in Chicago.

Gap of Expertise

Beetles, for instance, are by far the biggest category of any life-form, with 417,000 known species and perhaps 2 million to 2.5 million species. But only a handful of experts remain to look for and identify them.

Only four taxonomists are left who specialize in mites, tiny bugs that wreak serious havoc by carrying disease to plants and mammals, and only three for centipedes, none in the United States. Thirteen bivalve taxonomists are studying clams, but two of the three saltwater bivalve experts in the U.S. recently retired.

Concerned for the future, the National Science Foundation began six years ago to parcel out $750,000 awards to leading taxonomists. The five-year Partnerships for Enhancing Expertise in Taxonomy (PEET) grants are to be used to convince promising biology students that taxonomy remains a vital and crucial scientific pursuit.

The grant money provides stipends for postdoctoral students and covers travel, living, research, and equipment costs for field work for students and advisers. Sierwald is using her PEET grant to recruit and prepare young biologists for a lifetime of collecting and studying millipedes.

There are 10,000 known species of millipedes and perhaps 70,000 undiscovered species, but until Sierwald got busy only five millipede experts remained.

"One was in Russia, one in Tasmania, and three were in this country," Sierwald said. "The oldest was 74 years old, the others in their late 50s and 60s, and they had no students studying under them. There had been nobody getting ready to pick up where these scientists will leave off when they retire or pass from the scene."

Primeval, caterpillar-like creatures with segmented bodies and two dozen to 200 legs, millipedes live under and eat rotting vegetation in forests and gardens.

"We don't need 10,000 millipede experts, but we need a few," Sierwald said. "Millipedes decompose leaf litter on forest floors, and if they aren't there to do the job, the forest chokes on its own litter. With reforestation becoming so important in the world, we need somebody who knows the right millipedes for the right soils to get healthy, balanced forests."

Big Task

Certainly there is a lot of work left for taxonomists. Since Aristotle 2,300 years ago began the process of systematically cataloging the world's living things, science has identified probably fewer than 20 percent of the life-forms now living on Earth.

The biggest and most obvious organisms—mammals, birds, reptiles, and all manner of plants valuable to the human economy—are mostly (but not completely) known and cataloged, so PEET scholars aren't out looking for a new kind of elephant.

Instead, they study organisms that most people don't notice, couldn't imagine, or don't want to imagine. Among the grantees are experts in protozoa, flies, worms, mites, moss, and mollusks. And with 80 percent of Earth's living species yet to be discovered, proponents argue that the world needs many more taxonomists to find and describe them.

To understand what makes an ecosystem healthy for humans and other living things—or to recognize when one is in dangerous decline—you have to know exactly what plants and animals live there and how they interact. That is the job of taxonomists.

Moreover, by identifying and labeling all living things past and present, taxonomists have constructed the information storage system for all branches of biological sciences, one that is especially important to developing medicines and tracking the spread of disease.

The eclipse of taxonomy began in the late 1960s, when powerful electron microscopes allowed biologists to see into individual molecules of living organisms to watch and analyze chemical processes at work.

Offering insights into disease, aging, and other processes impossible to obtain by studying whole organisms, molecular biology became one of science's richest arenas.

In the last decade, computer-aided techniques have allowed researchers to use a single DNA molecule to determine an organism's entire genetic makeup. The process, called DNA sequencing, is now biology's hot new thing.

Shift of Focus

Most money for biological research is earmarked for developing new medicines and medical technology, for which molecular biology and DNA sequencing are perfectly suited.

On university campuses, molecular researchers became the big-ticket biology professors, with rich budgets and retinues of graduate students.

Taxonomy professors, who for centuries ruled the roost, often ended up isolated as quaint anachronisms to steer clear of until they could be pensioned off.

"I am hoping the enthusiasm for molecular biology will slow down," said David Hull, emeritus professor of the philosophy of science and ornithology at Northwestern University in Chicago. "Whole-organism biology is how we catalog and experience biodiversity, and for science to ignore it is dangerous.

"A molecular biologist wouldn't know a new species if he saw it, but if you run it past one of these old geezer taxonomists, he'll figure it out part by part, like a skilled diagnostician in medicine," said Hull. "Machines just aren't as good at diagnosis as a doctor who knows how to look at and where to touch a patient."

Millipedes, for example, exude unique odors from stink glands as a defense mechanism. "A trained guy can put his nose to ground, just take a whiff, and find millipedes," Hull said. "How are you going to program a computer to smell millipedes?"

Stirring Interest

Jason Bond, the first young scientist Sierwald recruited with her PEET grant, has been learning his craft collecting millipedes on expeditions to South Africa, Guatemala, Mexico, Jamaica, and California.

"When I started out in biology as an undergraduate, I wanted to go to medical school," said Bond, 33. "Then I became totally fascinated by evolutionary biology, and to do that, I thought I needed to know as much as I could about taxonomy."

His friends and many of his professors were almost horrified by the thought that he would turn to taxonomy. "A lot of people tried to convince me that I was making a terrible career decision," he said, but he persevered and did his Ph.D. thesis at Virginia Polytechnic Institute on trapdoor spiders.

Impressed by his scholarship, Sierwald asked him if he could bend his career path again, leaving his spider research to take a postdoctoral fellowship to study millipedes. He has moved to Eastern Carolina University for a tenure-track teaching and research job as a taxonomist.

Many taxonomic collections in museums and universities have gathered so much dust through decades of neglect that nobody has an accurate picture of what is in the collections. The PEET grantees are using their students to help remedy that situation.

"The last time anybody did a comprehensive study of all the known, described rove beetle specimens was 1840," said Margaret Thayer, an assistant insect curator at the Field Museum and an expert on the 47,000 known species of rove beetles. "It is important to reassess what we know."

More important, however, is to continue to attract young students to taxonomic careers, Thayer said. The disappearance of species and debate over conservation will make the scientists' work more important than at any time in history, she said.

"We need to know how species are related, how they branch out, how they figure into the tree of life," she said. "Right now, we have little twigs and branches sketched in for the tree of life, but we still don't know where much of it goes on the tree and how it connects with other things. Without taxonomy, we can't study a damn thing."

Copyright 2001 Chicago Tribune