The New York Times - 30.07.2019

D2 N THE NEW YORK TIMES, TUESDAY, JULY 30, 2019

In the jungles of Ivory Coast,

monkeys and chimps forage for

food, sleep in trees and travel in

groups. Following them are

primatologists like Jan Gogarten,

a researcher at the Robert Koch

Institute in Germany. But his

attention was drawn to another

presence. “We had these flies

always around,” he said.

Now he and his colleagues

have reported that some flies

stayed with mangabeys for up to

12 days. Some flies also tested

positive for a bacterium respon-

sible for many gruesome mon-

key and chimp deaths through

the years.

If the flies are one cause of the

spread of this disease, it suggests

a downside of social living —

more animals clustered together

could make an easier target for

insects and the diseases they may

carry.VERONIQUE GREENWOOD

UNWELCOME PASSENGERS

A Disease Is Killing

Monkeys, and Flies

May Be the Culprit

PHOTOGRAPHS BY JAN GOGARTEN

Top, a mangabey in Tai National

Park in Ivory Coast. Above, flies

can travel with mangabeys for

12 days or more.

In Chile’s Atacama Desert, Volcan Llullaillaco is Mars

on Earth — or about as close to it as you can get. At

22,000 feet above sea level, it’s the second-highest

active volcano on Earth. Most of the mountain is a

barren, red landscape of volcanic rock and dust.

While the ground can heat up to 90 degrees Fahr-

enheit, air temperatures rarely reach above freezing.

When snow falls, it turns to gas just as it hits the

earth. Occasionally, snow can collect in windblown

banks, which then melt into icy spires up to 16 feet

tall. The Spaniards called these “nieves penitentes,”

penitent ones, because they look like hooded monks

doing penance.

These conditions high up on the volcano made it

seem about as lifeless as Mars. But a team of re-

searchers have discovered microbes living in and

around the penitentes at 17,300 feet above sea level,

about 1,000 feet above the point at which vegetation

stops on Volcan Llullaillaco.

The scientists’ descriptions exemplify how life on

Earth consistently pushes our expected limits — and

may even offer clues to how or where life could exist

in similar environments elsewhere in the solar

system. JOANNA KLEIN

THE OUTER LIMITS

On a Mars-Like Landscape, Some Not-So-Alien Life Forms

PHOTOGRAPHS BY STEVEN K. SCHMIDT

Top, Lara Vimercati and Jack Darcy at a Chilean volcano. Above, algae in the snow.

Observatory

FINDINGS, EVENTS AND MORE

In a rain forest near Auckland,

New Zealand, a leafless kauri tree

stump rises a few feet off the

ground. These trees can become

giants: The country’s biggest,

Tane Mahuta, or the “Lord of the

Forest,” has grown 168 feet high,

with a 115-foot canopy.

But this stump (below, with sap

flow sensors attached) is just a

stump, so unassuming that most

would pass it by. One day, two

ecologists from Auckland Univer-

sity of Technology spotted it on a

hike. “A normal person would just

think it’s dead,” said Sebastian

Leuzinger. “It looks dead to a

point, but if you look a bit closer,

you can see living tissue. We both

said to each other: ‘It’s clearly not

dead. How does it live?’ ”

Naturalists have observed

living tree stumps in New Jersey,

the Sierra Nevadas, British Co-

lumbia and elsewhere. But for

more than 150 years, how the

stumps survived without leaves

for photosynthesis was a mystery.

Dr. Leuzinger and Martin Ba-

der discovered that the kauri

stump lives by sharing water with

neighboring trees. Most likely,

they’re connected through an

underground plumbing system

formed when their roots naturally

fused together, the researchers

reported recently.

JOANNA KLEIN

WOODEN LAZARUS

Tree Stumps Are Dead,

Right? Not This One

SEBASTIAN LEUZINGER

Lodestone, a naturally occurring
iron oxide, was the first persis-
tently magnetic material known
to humans. In modern times,

scientists have used magnets to
read and record data on hard
drives and form detailed images
of bones, cells and even atoms.
Throughout this history, one
thing has remained constant: Our
magnets have been made from
solid materials. But what if scien-
tists could make magnetic devices

out of liquids?
In a new study, researchers
managed to do exactly that.
“We’ve made a new material that
has all the characteristics of an
ordinary magnet, but we can
change its shape, and conform it
to different applications because

it is a liquid,” said Thomas Rus-
sell, the study’s lead author.
KNVUL SHEIKH

RESEARCHERS WITH PULL

This New Liquid

Is Magnetic,

And Mesmerizing

PHOTOGRAPHS BY XUBO LIU

Dye solution was added to oil

to track the flow field around

ferromagnetic droplets.

‘You have a very leaky system.’

Colm Sweeney, of NOAA and an author of a study finding that older

East Coast cities are releasing far more methane into the atmosphere

than had been estimated.

Humor, it has been said, “can be
dissected, as a frog can, but the
thing dies in the process.” Well,
get out the scalpels: We have dad
jokes to analyze. A new study
shows people find even the corni-

est one-liners funnier when
paired with a laugh track. And
funnier yet when accompanied by
laughter that seems genuine
rather than forced.
“If there’s a laugh there, you
can’t ignore it,” said Prof. Sophie
Scott, one of the study’s authors.
Take this zinger: “What does a
dinosaur use to pay bills? Tyran-

nosaurus checks.”

The study’s participants rated

that joke about two on a seven-

point scale. The rating rose to

more than two and a half when

paired with forced laughter, and

to more than three with genuine

laughter.NIRAJ CHOKSHI

TAKE MY PUNCHLINE, PLEASE

Getting No Respect

For Those Corny Jokes?

Try Using a Laugh Track

MICHELLE V. AGINS/THE NEW YORK TIMES

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