Featured Research

from universities, journals, and other organizations

Smarter than a first-grader? Crows can perform as well as 7- to 10-year-olds on cause-and-effect water displacement tasks

Date:
July 23, 2014
Source:
University of California - Santa Barbara
Summary:
In Aesop's fable about the crow and the pitcher, a thirsty bird happens upon a vessel of water, but when he tries to drink from it, he finds the water level out of his reach. Not strong enough to knock over the pitcher, the bird drops pebbles into it -- one at a time -- until the water level rises enough for him to drink his fill. New research demonstrates the birds' intellectual prowess may be more fact than fiction.

New Caledonian crow. Are crows smarter at cause and effect problems than first-graders?
Credit: Jolyon Troscianko

In Aesop's fable about the crow and the pitcher, a thirsty bird happens upon a vessel of water, but when he tries to drink from it, he finds the water level out of his reach. Not strong enough to knock over the pitcher, the bird drops pebbles into it -- one at a time -- until the water level rises enough for him to drink his fill.

Related Articles


Highlighting the value of ingenuity, the fable demonstrates that cognitive ability can often be more effective than brute force. It also characterizes crows as pretty resourceful problem solvers. New research conducted by UC Santa Barbara's Corina Logan, with her collaborators at the University of Auckland in New Zealand, demonstrates the birds' intellectual prowess may be more fact than fiction. Her findings appear today in the scientific journal PLOS ONE.

Logan is lead author of the paper, which examines causal cognition using a water displacement paradigm. "We showed that crows can discriminate between different volumes of water and that they can pass a modified test that so far only 7- to 10-year-old children have been able to complete successfully. We provide the strongest evidence so far that the birds attend to cause-and-effect relationships by choosing options that displace more water."

Logan, a junior research fellow at UCSB's SAGE Center for the Study of the Mind, worked with New Caledonian crows in a set of small aviaries in New Caledonia run by the University of Auckland. "We caught the crows in the wild and brought them into the aviaries, where they habituated in about five days," she said. Keeping families together, they housed the birds in separate areas of the aviaries for three to five months before releasing them back to the wild.

Getting individual crows into the testing room proved to be an immediate challenge. "You open the testing room door and then open the aviary door, with the idea that the bird you want is going to fly through into the testing room," she said. But with four birds in an aviary, directing a particular test subject is tricky at best.

"So I thought, let's pretend the sky's the limit and I can train them to do whatever I want," Logan said. "I started by pointing at the one I wanted and continuing to point until he or she flew out. I got to the point where I could stand outside the aviary and point at the one I wanted and it would fly out while the other birds stayed put."

Two birds in particular -- 007 and Kitty -- became so well trained that Logan had only to call them by name and they'd fly into the testing room.

The testing room contained an apparatus consisting of two beakers of water, the same height, but one wide and the other narrow. The diameters of the lids were adjusted to be the same on each beaker. "The question is, can they distinguish between water volumes?" Logan said. "Do they understand that dropping a stone into a narrow tube will raise the water level more?" In a previous experiment by Sarah Jelbert and colleagues at the University of Auckland, the birds had not preferred the narrow tube. However, in that study, the crows were given 12 stones to drop in one or the other of the beakers, giving them enough to be successful with either one.

"When we gave them only four objects, they could succeed only in one tube -- the narrower one, because the water level would never get high enough in the wider tube; they were dropping all or most of the objects into the functional tube and getting the food reward," Logan explained. "It wasn't just that they preferred this tube, they appeared to know it was more functional."

However, she noted, we still don't know exactly how the crows think when solving this task. They may be imagining the effect of each stone drop before they do it, or they may be using some other cognitive mechanism. "More work is needed," Logan said.

Logan also examined how the crows react to the U-tube task. Here, the crows had to choose between two sets of tubes. With one set, when subjects dropped a stone into a wide tube, the water level raised in an adjacent narrow tube that contained food. This was due to a hidden connection between the two tubes that allowed water to flow. The other set of tubes had no connection, so dropping a stone in the wide tube did not cause the water level to rise in its adjacent narrow tube.

Each set of tubes was marked with a distinct color cue, and test subjects had to notice that dropping a stone into a tube marked with one color resulted in the rise of the floating food in its adjacent small tube. "They have to put the stones into the blue tube or the red one, so all you have to do is learn a really simple rule that red equals food, even if that doesn't make sense because the causal mechanism is hidden," said Logan.

As it turns out, this is a very challenging task for both corvids (a family of birds that includes crows, ravens, jays and rooks) and children. Children ages 7 to 10 were able to learn the rules, as Lucy Cheke and colleagues at the University of Cambridge discovered in 2012. It may have taken a couple of tries to figure out how it worked, Logan noted, but the children consistently put the stones into the correct tube and got the reward (in this case, a token they exchanged for stickers). Children ages 4 to 6, however, were unable to work out the process. "They put the stones randomly into either tube and weren't getting the token consistently," she said.

Recently, Jelbert and colleagues from the University of Auckland put the New Caledonian crows to the test using the same apparatus the children did. The crows failed. So Logan and her team modified the apparatus, expanding the distance between the beakers. And Kitty, a six-month-old juvenile, figured it out. "We don't know how she passed it or what she understands about the task," Logan said, "so we don't know if the same cognitive processes or decisions are happening as with the children, but we now have evidence that they can. It's possible for the birds to pass it.

"What we do know is that one crow behaved like the older children, which allows us to explore how they solve this task in future experiments," she continued. Research on causal cognition using the water displacement paradigm is only beginning to get at what these crows know about solving problems. This series of experiments shows that modifying previous experiments is useful for gaining a deeper understanding.

The research on the crows is part of a larger project Logan is working on to compare the cognitive powers of crows with those of grackles. "So far, no smaller-brained species have been tested with the tests we use on the crows, and grackles are smaller-brained," she said. "But they're really innovative. So they may have a reason to pay attention to causal information like this."

This research was supported by the National Geographic Society/Waitt Grants Program.

The next research phase will begin next month, after the grackles' breeding season ends and they are ready to participate.


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. The original article was written by Andrea Estrada. Note: Materials may be edited for content and length.


Journal Reference:

  1. Corina J. Logan, Sarah A. Jelbert, Alexis J. Breen, Russell D. Gray, Alex H. Taylor. Modifications to the Aesop's Fable Paradigm Change New Caledonian Crow Performances. PLoS ONE, 2014; 9 (7): e103049 DOI: 10.1371/journal.pone.0103049

Cite This Page:

University of California - Santa Barbara. "Smarter than a first-grader? Crows can perform as well as 7- to 10-year-olds on cause-and-effect water displacement tasks." ScienceDaily. ScienceDaily, 23 July 2014. <www.sciencedaily.com/releases/2014/07/140723180824.htm>.
University of California - Santa Barbara. (2014, July 23). Smarter than a first-grader? Crows can perform as well as 7- to 10-year-olds on cause-and-effect water displacement tasks. ScienceDaily. Retrieved November 1, 2014 from www.sciencedaily.com/releases/2014/07/140723180824.htm
University of California - Santa Barbara. "Smarter than a first-grader? Crows can perform as well as 7- to 10-year-olds on cause-and-effect water displacement tasks." ScienceDaily. www.sciencedaily.com/releases/2014/07/140723180824.htm (accessed November 1, 2014).

Share This



More Plants & Animals News

Saturday, November 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Watch Baby Goose Survive A 400-Foot Cliff Dive

Watch Baby Goose Survive A 400-Foot Cliff Dive

Buzz60 (Oct. 31, 2014) For its nature series Life Story, the BBC profiled the barnacle goose, whose chicks must make a daredevil 400-foot cliff dive from their nests to find food. Jen Markham has the astonishing video. Video provided by Buzz60
Powered by NewsLook.com
World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Alcoholic Drinks In The E.U. Could Get Calorie Labels

Alcoholic Drinks In The E.U. Could Get Calorie Labels

Newsy (Oct. 31, 2014) A health group in the United Kingdom has called for mandatory calorie labels on alcoholic beverages in the European Union. Video provided by Newsy
Powered by NewsLook.com
Malaria Threat in Liberia as Fight Against Ebola Rages

Malaria Threat in Liberia as Fight Against Ebola Rages

AFP (Oct. 31, 2014) Focus on treating the Ebola epidemic in Liberia means that treatment for malaria, itself a killer, is hard to come by. MSF are now undertaking the mass distribution of antimalarials in Monrovia. Duration: 00:38 Video provided by AFP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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