Biology Reference
In-Depth Information
her fieldwork in her study of a group of rare South American mammals in the Cerrado. The
maned wolf, jaguar, puma, giant anteater, and giant armadillo of the continent's pampas and
central savannas are vestiges of a rich Serengeti-like fauna that flourished in the Pleistocene
epoch, 15,000 years ago. Today, their secretive behavior, low population densities, and abil-
ity to hide in the waist-high grass make sightings of these charismatic vertebrates quite rare.
Their presence in the agricultural landscape remained an open question. The small size of
the existing Cerrado parks and the wide-ranging nature of these species probably meant that
some of them lurked out there in the ranchlands as well.
Field biologists who study the habitat use of rare mammals look for any sign: a scrape, a
footprint, or the unexpectedly precious gift, a dropping. Miraculous advances in molecular
biology have enabled researchers to extract strands of DNA and hormones from animal drop-
pings, transforming the lowly fecal deposit into a gold mine of information. A scat sample
can reveal the species of the depositor, individual identity, sex, reproductive status, diet, and
health. Moreover, accumulated droppings from any single species, giant anteater or jaguar,
yield the most prized data of all for rarities—density, home range, and population size.
The challenge, of course, is to find the fresh material from secretive animals that are often
solitary and only part-time above-grounders, as is the giant armadillo. The first three years of
Carly's study, and other studies like it, had begun to show such promise that by 2010 human-
dog research teams had gone global. Scent dogs are now used to study grizzly bears, Mexican
wolves, wolverines, fishers, Javan rhinos, Indochinese tigers, Amur tigers, and other secret-
ive mammals. The roots of this booming human-canid collaboration, however, trace back to
an animal shelter outside Seattle, Washington.
If popular belief grants cats nine lives, dogs most certainly deserve at least two or three.
Heath Smith told me that he had no opinion on animal karma when he entered the local shel-
ter in Enumclaw, Washington, on a gray day in March 2004. He was not on a mercy expedi-
tion. Once inside the pound, Smith began bouncing a tennis ball off the concrete floor. Some
dogs wagged their tails and rose to lick the visitor's hand but ignored the ball. A long-legged
black Labrador pressed against the edge of his cage. He ignored the stranger but fixated on
the delightful object Smith tossed in the air. The dog trembled with excitement and panted
heavily. Here on display was precisely the kind of overwrought behavior bound to discour-
age even bighearted adopters. The shelter employee offered some details. “He was picked up
running along the highway; must have gotten lost while hunting. You sure that's the one you
want?” Heath nodded after taking a minute to confer with his boss by cell phone. “Great,”
answered the relieved keeper, “because he had twenty-four hours left.”
