When a male African savanna elephant folds his ears while simultaneously waving them, he’s ready for a fight. When a female folds her ears and accompanies the action with an ear flap, that means she’s also issuing a serious threat. But when elephants come together and fold their ears while also rapidly flapping them, the animals are expressing a warm, affiliative greeting that is part of their bonding ceremonies.
Elephants possess an incredibly rich repertoire of communication techniques, including hundreds of calls and gestures that convey specific meanings and can change depending on the context. Different elephant populations also exhibit culturally learned behaviors unique to their specific group. Elephant behaviors are so complex, in fact, that even scientists may struggle to keep up with them all. Now, to get the animals and researchers on the same page, a renowned biologist who has been studying endangered savanna elephants for nearly 50 years has co-developed a digital elephant ethogram, a repository of everything known about their behavior and communication.
“Without a multimedia approach, I see it as impossible to properly show and explain the behavior of a species, and we hope this will inspire other scientists to take a similar approach for other species,” says Joyce Poole, co-founder and scientific director of ElephantVoices, a nonprofit science and conservation organization, and co-creator of the new ethogram. “At a time when biodiversity is plummeting and the lives of elephants are being heavily impacted by humans, we also want to spell out to the world what we stand to lose.”
Poole built the easily searchable public database with her husband and research partner Petter Granli after they came to realize that scientific papers alone would no longer cut it for cataloging the discoveries they and others were making. The Elephant Ethogram currently includes more than 500 behaviors depicted through nearly 3,000 annotated videos, photographs and audio files. The entries encompass the majority, if not all, of typical elephant behaviors, which Poole and Granli gleaned from more than 100 references spanning more than 100 years, with the oldest records dating back to 1907. About half of the described behaviors came from the two investigators’ own studies and observations, while the rest came from around seven other leading savanna elephant research teams.
While the ethogram is primarily driven by Poole and Granli’s observations, “there are very few, if any, examples of behaviors described in the literature that we have not seen ourselves,” Poole points out. The project is also just beginning, she adds, because it is meant to be a living catalog that scientists actively contribute to as new findings come in.
“We know elephants behave and communicate with each other in complex ways. But until now, we have barely scratched the surface of just how complex that behavior and communication is,” says Lucy Bates, a visiting research fellow specializing in elephant cognition at the University of Sussex in England, who was not involved in creating the ethogram. “Now we have this foundation—freely available in the public domain—from which we can build a much more comprehensive picture of what elephants are doing and why.”
Ethograms are compilations of animal activities and behaviors, either in a specific context or for a species overall. Researchers use ethograms for studying behavior and making comparisons among ages, sexes, families, populations or different species. While a digital ethogram exists for laboratory mice, and another has been published in written form for chimpanzees, Poole and Granli believe the exhaustive, digitized Elephant Ethogram is the first of its kind for any nonhuman wild animal. The multimedia-based nature of the project is important, Poole adds, because with descriptions based only on the written word, audio files or photographs, “it is hard to show the often subtle differences in movement that differentiate one behavior from another.”
When Poole began studying elephants in 1975, scientists knew very little about their behavior. Her early research focused on musth, a periodic reproductive condition in male elephants that is characterized by testosterone surges and heightened aggression. Poole noted that the animals waved their ears as a threat, and she sometimes also noticed a low, pulsating sound accompanying this movement. At first, she thought it was produced by the ears whooshing through the air, but she soon realized that the sound was a vocalization. She began to wonder if the animals were making other sounds too low for her ears to fully detect.
To follow up on these observations, Poole teamed up with acoustic biologist Katy Payne. Together, they revealed that the different rumbles elephants produce contain some frequencies below the level of human hearing and that some of these sounds are so powerful they may be heard by other elephants miles away. This discovery helped solve a number of elephant mysteries, including how members of a family are able to quickly find one another after they split up and how the animals, without seeming to make a sound, are able to act in complete unison when a threat is detected.
“For a long time, people talked about elephant ESP,” Poole says. “Some vocalizations they make are so powerful and are transmitted through the ground as vibrations, acting like a kind of bush telegraph for elephants saying, ‘There’s trouble.’”
As Poole continued to study elephants, she realized that the meaning of many of the behaviors she was documenting also changed depending on the context. Tail swatting, for example, is usually used by one elephant to tell another to back off because it is standing too close. But mothers also use tail swatting to keep tabs on infants standing behind them. In still other contexts, elephants use it to pester or nag for attention.
For now, the majority of entries in the Elephant Ethogram come from three locations: Maasai Mara National Reserve, or the Mara, and Amboseli National Park in Kenya and Gorongosa National Park in Mozambique. The limited number of sites do not necessarily affect the breadth of behaviors in the database, however, because most elephant behaviors are conserved across populations. But the frequency of certain behaviors may differ depending on the study site. Elephants at Amboseli, for example, never dig for minerals because the soil there is salty, and Poole has only once seen an Amboseli elephant shake a tree to knock down seed pods because there are very few trees in the area. In the Mara, on the other hand, elephants often dig for minerals. And in Gorongosa, they frequently shake trees for seeds.
Stark cultural differences can also exist among populations. During the Mozambican Civil War, 90 percent of the elephants in Gorongosa were killed for their ivory and meat. Nearly 30 years later, the elephants there still act fearfully and aggressively toward people. “Their behavior is very different from Amboseli and the Mara, where we see almost no defensive behaviors toward people,” Poole says. “As Gorongosa experiences a rebirth under new protection and restoration, how long will it take for elephants to abandon those traditions?”
The answer will likely someday be cataloged in the Elephant Ethogram. Now that the project is online, Poole hopes other researchers will begin contributing their own observations and discoveries, broadening the database to include cultural findings from additional savanna elephant populations and unusual behaviors Poole and Granli might have missed. Wildlife photographer Kelly Fogel, for example, recently submitted rare footage of an elephant eating her own placenta after giving birth. And Elephant Aware, a nonprofit conservation group, sent in a similarly uncommon video of a calf trying to suckle from her dead mother. “Now that the Elephant Ethogram is publicly available, we hope that more of our colleagues will share unusual footage from their populations,” Poole says.
Already, though, the ethogram is an “invaluable tool” for young scientists who are interested in conducting field research on elephants, says Michael Pardo, a postdoctoral researcher studying African elephant vocal communication at Colorado State University. The ethogram will also help ensure that scientists are talking about the same thing when referring to a specific behavior, he says. “This is really important, because all too often in the scientific literature, confusion about terminology and definitions can result in researchers talking past one another,” Pardo adds.
Daniela Hedwig, a research associate at the Elephant Listening Project at Cornell University, agrees that the Elephant Ethogram is “a monumental achievement.” Hedwig studies communication in forest elephants in other parts of Africa, and the savanna elephant database will be “an extremely useful repository to draw comparisons between the two species,” she says.
Cynthia Moss, director of the Amboseli Trust for Elephants in Kenya, says the ethogram will also be particularly helpful in assessing the lives of captive elephants. Elephants held at circuses, zoos and work environments are deprived of intricate social connections and the ability to travel and to interact with a diverse environment, Poole says. This causes them to suffer from boredom and to develop stereotypic behaviors, such as rocking back and forth. The Elephant Ethogram can shed light on the severity of behavior differences between captive and wild animals, Poole says, and strengthen the case for ending elephant captivity.
Moss adds that the database will also be a valuable tool for wildlife managers and conservationists who seek to differentiate between natural, healthy elephant behaviors and ones induced by stressful conditions, such as poaching and habitat loss. The need for such comparisons is growing as elephants in the wild face mounting pressure to tailor their behaviors to a people-dominated world. “Elephants’ ability to culturally adapt is going to be critical for their future survival,” Poole says. “As they are forced to change, we’re going to learn a lot more about their creativity and flexibility.”
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