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ASU professor continues to find surprises in studies in Uganda chimp project.
Less than 300,000 chimps in the wild; those numbers are expected to drop.
February 10, 2016

ASU primatologist continues to find surprises in a chimpanzee stronghold in Uganda

Kevin Langergraber has been studying chimpanzees in the wild for 15 years.

Before he became a professor and had to teach eight months out of the year, he’d spend six months to a year at a time in the field, 12 hours a day, seven days a week.

“The most surprising thing about the job is that you can still be surprised by the job,” said Langergraber, a primatologist and assistant professor in the School of Human Evolution and Social ChangeThe School of Human Evolution and Social Change is a unit of the College of Liberal Arts and Sciences. at Arizona State University.

“After a while you’d think, ‘OK — I’ve spent thousands of hours watching these guys. What is going to surprise me when I wake up and spend my 12-hour day in the forest?’ ” he said. “Despite all this time I’m still shocked when I go back and the chimps show me something I hadn’t seen before.”

Langergraber, who has been at ASU for a year and a half, co-directs the Ngogo Chimpanzee Project in Kibale National Park, Uganda, home to the largest wild chimp community in the world. About 200 individuals live in the 35-square-kilometer preserve in the middle of the 800-square-kilometer national park. The community has been studied since 1995.

An adult chimp.

Django, an adult male
chimp in the Ngogo
Chimpanzee Project
in Kibale National
Park, Uganda.
Top: Penelope, an
adult chimp, with
her female infant,

Photos by Kevin

One big surprise came last summer. In the beginning of the season, food was lean. When food supplies are down, chimps are hard to find because they split into tiny groups to forage. But food availability crept up, to the point where three of their favorite fruits ripened at the same time.

“They basically had more food than they knew what to do with at this point,” Langergraber said. “It was falling off the trees and sitting on the ground uneaten.”

About 30 adult females with 60 kids congregated. “There were these huge parties, these huge hordes of chimpanzees, which was very unusual, especially for females, which are more solitary than male chimpanzees,” he said. “They began exhibiting really male-like behavior.”

Chimps hunt monkeys, but it’s almost always done by males, in groups. Females do hunt, but much less than males.

“(The females) started going on this little mini-hunting binge, where they were hunting almost every day over the course of a few weeks,” Langergraber said. “That is something I’d never expected to see in my life. … I’ve been there for 15 years, and this is something out of the blue I think will be important for learning about why in general is it males hunt more than females and questions like that.”

Chimpanzees are classified as endangered by the International Union for the Conservation of Nature. They’re endangered throughout their range across equatorial Africa. The IUCN estimates there are less than 300,000 chimps in the wild, according to a rough estimate made in 2003. Those numbers are expected to drop.

“Due to high levels of exploitation, loss of habitat and habitat quality due to expanding human activities, this species is estimated to have experienced a significant population reduction in the past 20 to 30 years, and it is suspected that this reduction will continue for the next 30 to 40 years,” the IUCN Red List said on its website.

“Kibale National Park is probably the last stronghold of chimpanzees in the country of Uganda,” Langergraber said. “We don’t know how exactly how many chimps are there.”

Chimpanzees are hard to count. They live in communities with permanent members, but it’s like a university — you never see the whole community in one place at one time. Chimps make nests every night to sleep in. Counting the nests has been the way the population size is estimated — anywhere from 800 to 1,000 in Kibale.

“We know these nest surveys aren’t terribly accurate,” Langergraber said. “One of the things I’m doing in my research is to really find out how many chimpanzees are in Kibale National Park. We’re doing that through a genetic census.”

Park anti-poaching patrols pick up chimp feces on their patrols. Langergraber does genetic analyses of the samples.

“Then you get a genetic fingerprint for that individual,” he said. “We’re doing this over time. It’s a long-term process. We’ve been doing it for a couple of years now. Based on how many times you’re collecting the same individual over again, versus an entirely new individual you haven’t seen before, you can get an estimate of the population size.”

It’s much more accurate than counting nests.

“Our preliminary results suggests there may be twice as many chimpanzees living in Kibale National Park as we previously thought,” he said. “They’re doing well in Kibale, for now.”

Poaching is widespread throughout the whole park. Eating chimpanzee is actually taboo in this part of Uganda, but poachers go after bush pig and duikers — tiny forest antelope — and chimps become caught in the snares. “They’ll spear it and feed it to their hunting dogs,” Langergraber said. “Poaching has increased, especially for larger game, like elephants.”

The research presence in Ngogo wards poachers away from that area of the park. Two three-person snare-removal teams — ex-poachers lured from the life with good stable jobs — patrol Ngogo in conjunction with local wildlife-authority officers.

A scientist in a forest. “Our guys work with the (Uganda Wildlife Authority) rangers, who have guns, which really helps to protect the park,” said Langergraber (pictured left). The project hopes to hire a third team for patrols.

Research with chimpanzees is long-term. Chimps are long-lived and slow-producing — one infant every five years.

“That makes them very difficult to study,” Langergraber said. “Just now chimpanzee researchers have been out there long enough to really document the whole lifespans of chimpanzees. In particular one of the things we’re interested in in evolutionary biology is what determines which individuals are reproductively successful. ... Things like that are important stuff that’s coming up now and in the future.”

There are multiple chimps at Ngogo more than 60 years old, including one very rare great-grandmother.

“We’ve got a bunch of old ladies running around the forest there,” Langergraber said. “It’s a good place to be a chimp, Ngogo.”

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Scientists prove Einstein's theory of relativity.
ASU's Krauss was right about gravitational waves.
February 11, 2016

ASU's Krauss hails discovery, which he predicted, as important as the invention of the telescope

Everything shifted this morning.

In the 100th-anniversary year of Einstein’s theory of relativity, scientists announced they have proved it.

Using a stunning display of technological prowess, a group of physicists measured gravitational waves, a ripple in the fabric of space caused by the collision of two immense objects far out in the universe.

The discovery is on par with the invention of the telescope, said Lawrence KraussKrauss is also Foundation Professor of the School of Earth and Space Exploration, and director of its Origins Project. The School of Earth and Space Exploration is an academic unit of the College of Liberal Arts and Sciences., a theoretical physicist and cosmologist at Arizona State University.

“It heralds what I think is the beginning of the new astronomy for the 21st century,” Krauss said. “Gravitational-wave astronomy will be the astronomy of the 21st century. It’s opened a new window on the universe, just like the telescope in some sense or when we first used radio waves to explore the universe.”

Researchers at the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO), a joint project between the Massachusetts Institute of Technology and the California Institute of Technology, used two detectors at opposite ends of the country to measure a change in length down to a tolerance of one ten-thousandth of a proton.

“Using gravitational waves to explore the universe will allow us to see things we could have never seen before,” Krauss said. “We’ll be exploring science in a domain we’ve never seen before. It will also allow us to explore objects in the universe we’ve never seen before.”

The LIGO experiment observed the collision of two black holes. Black holes are at the center of virtually every large galaxy, and their dynamics may be related to the dynamics of galaxy formation. It’s a chicken-and-egg question: Which formed first?

Two incredibly immense black holes collided, converting a mass three times the size of the sun into energy in a single second, sending out a ripple in space and time.

“It allows us to see things that are just truly mind-boggling,” Krauss said. “A black hole with a mass 39 times the mass of our sun collides with another black hole 26 times the mass of the sun, comes together to make one big black hole that’s 62 times the mass of the sun. If you do your addition, 62 is not 39 plus 26, it’s three solar masses smaller. Three solar masses of energy went in a second into gravitational waves. … Our sun over 10 billion years is only going to convert a small fraction of its mass into energy by burning 100 million hydrogen bombs every second. But in one second or so, in a very short time — BOOM — three times the mass of the sun was converted by E=mc²In physics, mass–energy equivalence is a concept formulated by Albert Einstein that explains the relationship between mass and energy. It states every mass has an energy equivalent and vice versa — expressed using the formula E=mc² where E is the energy of a physical system, m is the mass of the system, and c is the speed of light in a vacuum (about 3×108 m/s). — Wikipedia into energy. It’s unfathomable. It just disappeared. Imagine our sun just disappearing in a second.”

“Gravitational-wave astronomy will be the astronomy of the 21st century. It’s opened a new window on the universe, just like the telescope in some sense or when we first used radio waves to explore the universe.”
— Lawrence Krauss, ASU theoretical physicist and cosmologist

In order to detect gravitational waves, researchers had to build a detector. There are two detectors: one in Louisiana and the other in Washington state, each with two perpendicular arms 4 kilometers long. When a gravitational wave comes along, one arm gets shorter and one gets longer periodically, and vice versa. Gravitational waves change length. What the physicists looked for is a disturbance in both detectors, separated by the time it would take light to travel from one detector to the other. (Gravitational waves travel at the speed of light.)

They fired lasers down the arms and bounced them off mirrors at either end. The laser path lengths are equal under normal circumstances, but not when a gravitational wave passes through.

“It’s a testament to human perseverance and ingenuity,” Krauss said. “What was required to build a detector to detect gravitational waves is unbelievable.”

It’s like being in California and detecting a leaf falling in Virginia. The system is so sensitive a truck hitting a pothole miles away threw it off in the early years when it started operating in 2002. The arms are so long that the curvature of the Earth is a measurable 1 meter (vertical) difference over the 4-kilometer length of each arm. “The most precise concrete pouring and leveling imaginable was required to counteract this curvature and ensure that LIGO’s vacuum chambers were truly ‘flat’ and level,” the lab’s website said. The detectors are so precise continental drift had to be taken into consideration, Krauss said.

“They had to be able to measure the change in length of a 4-kilometer-long tunnel by an amount equal to one ten-thousandth the size of a proton,” he said. “When you say that, it’s just amazing. It’s just amazing that human beings could do that. They had to push quantum technology to its limits. Even the quantum fluctuations of atoms in the mirror are such that even those have to be controlled. It’s just amazing what they can do. It’s proof that truth is stranger than fiction. Science-fiction writers wouldn’t dare to even propose it, but it’s been done. It’s taken 20 years of hard work by thousands of physicists; there are more than 1,000 people working on that collaboration.”

LIGO will allow the laws of physics to be tested in domains never seen before, like the event horizon of black holes, “which is that region inside of which you never get out, and which, if you’re near, strange things happen — if you’ve seen the movie ‘Interstellar,’ time dilates and everything else,” Krauss said. “It’ll be a whole new type of astronomy.”

He appreciated the poetics of the discovery happening in the anniversary year of relativity.

“It’s beautifully fitting that on the 100th anniversary of the development of general relativity, when Einstein first proposed the existence of gravitational waves, that they’ve finally been directly discovered,” he said. “It’s superlatives all over. It’s an amazing piece of work by an amazing group of scientists who were dedicated to doing something that appeared impossible, to discover something that opens a new window on the universe. And every time we open a new window on the universe, we’ve been surprised. I’m sure there will be surprises.”

Krauss has taken abuse from some quarters for teasing the announcement on his Twitter feed, once this past September and again in January. (One astrophysicist claimed to be “appalled” by the tweets.) Krauss thought drumming up interest in a major discovery was the right thing to do.

“If scientists are excited, I didn’t see why the public shouldn’t be,” he said. “No one on the project told me anything in confidence. I just heard the rumor, and it turned out to be true. … The net result was hundreds of articles are being prepared now for this result that wouldn’t be there if I hadn’t in some sense laid the groundwork. … I think I’d say I was doing God’s work, if I believed in God.”


Top image: A visualization of gravitational waves produced by two orbiting black holes. Image by Henze/NASA.