Featured Research

from universities, journals, and other organizations

Not Only Dogs, But Deer, Monkeys And Birds Bark To Deal With Conflict

Date:
July 15, 2009
Source:
University of Massachusetts Amherst
Summary:
Biologically speaking, many animals besides dogs bark, according to evolutionary biologists, but domestic dogs vocalize in this way much more than birds, deer, monkeys and other wild animals that use barks. The reason is related to dogs' 10,000-year history of hanging around human food refuse dumps, she suggests.

Why do dogs bark so much? A recent paper by UMass Amherst evolutionary biologist Kathryn Lord and colleagues suggests that it has more to do with their evolutionary history as scavengers in dumps than their desire to communicate with humans.
Credit: Raymond Coppinger

Biologically speaking, many animals besides dogs bark, according to Kathryn Lord at the University of Massachusetts Amherst, but the evolutionary biologist also says domestic dogs vocalize in this way much more than birds, deer, monkeys and other wild animals that use barks. The reason is related to dogs’ 10,000-year history of hanging around human food refuse dumps, she suggests.

In her recent paper in a special issue of the journal, Behavioural Processes, Lord and co-authors from nearby Hampshire College also provide the scientific literature with its first consistent, functional and acoustically precise definition of this common animal sound.

As Lord, a doctoral candidate in organismic and evolutionary biology at UMass Amherst, explains, “We suggest an alternative hypothesis to one that many biologists seem to accept lately, which seeks to explain dog barking in human-centric terms and define it as an internally motivated vocalization strategy.” In the researchers’ view, however, barking is not a special form of communication between dogs and humans. “What we’re saying is that the domestic dog does not have an intentional message in mind, such as, ‘I want to play’ or ‘the house is on fire,’” explains Lord.

Rather, she and colleagues say barking is the auditory signal associated with an evolved behavior known as mobbing, a cooperative anti-predator response usually initiated by one individual who notices an approaching intruder. A dog barks because she feels an internal conflict―an urge to run plus a strong urge to stand her ground and defend pups, for example. When the group joins in, the barks intimidate the intruder, who often flees.

“We think dogs bark due to this internal conflict and mobbing behavior, but domestic dogs bark more because they are put, and put themselves into, conflicting situations more often,” she says.

The reason traces back to the first dogs that started hanging around human food dumps about 8,000 to 10,000 years ago. They would have experienced a serious disadvantage if they had run a mile away every time a human or other animal approached. As Lord explains, “In evolutionary terms, dogs self-selected the behavior of sticking around, overcoming their fear and being rewarded by getting to eat that meal before some other dog got it. Thus these animals allow people to get unusually close. The scared ones die while those less scared stay, eat, survive and reproduce. So they inherit the tendency.”

She adds, “By contrast, wild animals like wolves have a very long flight distance. They hear something and they run before you’d ever see them. Dogs hang around, but now they have committed to holding their ground and the closer an ‘intruder’ gets, the more likely mobbing is to occur rather than running away.”

An example of the domestic environment (rather than the dog’s own behavior) that increases barking is the animal stuck behind a fence with a person approaching, says Lord. “The dog may either feel anxiety or excitement at seeing a stranger but in either case the dog is prevented from approaching or fleeing. This creates conflict, and thus barking.”

Several technical pages of the researchers’ recent paper identify eight different parameters in three categories which must be met in order to classify a given vocalization as a bark. These include tonality, noise, pitch, volume or amplitude, abrupt onset and pulse duration, for example.

In their view, barking is not self-referential communication to convey a message, but a short, loud sound characterized by combining both noise and tonal sounds, which is unusual in animal calls. This definition widens the bark’s usefulness as a functional behavior seen in many animals, though domesticated dogs display it more often. “Using this definition, even birds bark, and certainly many mammals besides canines, including baboons and monkeys, rodents and deer also bark,” Lord explains. “In a whole bunch of mammals and birds, what they do in such conflicted situations is bark.”

This evolutionary view of barking does not sit well with some pet owners who insist that Buffy communicates with them by barking, the researchers acknowledge. “We understand the objection when people say their dogs bark for supper or to get out and play,” Lord says. “Dogs do quickly learn the simple cause-and-effect relationship between their bark at 10 p.m. and the fact that you’ll get right up and take them outdoors. It’s true, but in our view it’s going too far to suggest the animal is intentionally referring to a specific activity. Rather, it has just learned cues, as it does when it learns to sit or beg for a treat.”


Story Source:

The above story is based on materials provided by University of Massachusetts Amherst. Note: Materials may be edited for content and length.


Cite This Page:

University of Massachusetts Amherst. "Not Only Dogs, But Deer, Monkeys And Birds Bark To Deal With Conflict." ScienceDaily. ScienceDaily, 15 July 2009. <www.sciencedaily.com/releases/2009/07/090714210137.htm>.
University of Massachusetts Amherst. (2009, July 15). Not Only Dogs, But Deer, Monkeys And Birds Bark To Deal With Conflict. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2009/07/090714210137.htm
University of Massachusetts Amherst. "Not Only Dogs, But Deer, Monkeys And Birds Bark To Deal With Conflict." ScienceDaily. www.sciencedaily.com/releases/2009/07/090714210137.htm (accessed April 18, 2014).

Share This



More Plants & Animals News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
Powered by NewsLook.com
Flamingo Frenzy Ahead of Zoo Construction

Flamingo Frenzy Ahead of Zoo Construction

AP (Apr. 17, 2014) With plenty of honking, flapping, and fluttering, more than three dozen Caribbean flamingos at Zoo Miami were rounded up today as the iconic exhibit was closed for renovations. (April 17) Video provided by AP
Powered by NewsLook.com
Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins