Featured Research

from universities, journals, and other organizations

Fishy Cooperation: Scientists Discover Coordinated Hunting Between Groupers, Giant Moray Eels

Date:
December 23, 2006
Source:
Public Library of Science
Summary:
Videos and field data reveal that the grouper and the giant moray eel cooperate to hunt together, each taking on different roles. Such cooperation has only been observed in mammals and birds.

A grouper signal to a giant moray eel resting in a cave by shaking its head in front of the moray.
Credit: Image from video courtesy of Public Library of Science / Frans B. M. de Waal, PLoS Biology

It is commonly thought that animals can be arranged along a ladder of intelligence—a sort of modern-day Scala Naturae—with humans inevitably at the top, followed by our close relatives, the primates, all the way down to fish and other slimy creatures.

Over the past decade, this ladder has been challenged by claims of high intelligence and great social complexity in other animals. For example, spotted hyenas (Crocuta crocuta) establish hierarchies in which dominant females support the rank contests of their daughters. Bottlenose dolphins (Tursiops aduncus) form “political” coalitions every bit as complex as those of chimpanzees. Caledonian crows (Corvus moneduloides) not only use tools in the wild, but also modify tools in the lab, an ability once thought to define humans.

And now come the fish. It started with a provocative challenge to primate supremacy with the claim that “culture” (that is, socially transmitted behavior) is at least as well developed in fish as it is in primates. While this may be a bit of an exaggeration, a new study on cooperative behavior by Redouan Bshary and his colleagues really makes one wonder if there is anything fish cannot do.

The article describes the astonishing discovery of coordinated hunting between groupers (Plectropomus pessuliferus) and giant moray eels (Gymnothorax javanicus) in the Red Sea. These two species make a perfectly complementary pair. The moray eel can enter crevices in the coral reef, whereas the grouper hunts in open waters around the reef. Prey can escape from the grouper by hiding in a crevice and from the moray eel by leaving the reef, but prey has nowhere to go if hunted by a combination of these two predators.

The article offers a description and accompanying videos, such as the one showing a grouper and eel swimming side by side as if they are good friends on a stroll. It also offers quantification, which is truly hard to achieve in the field, of the tendencies involved in this mutually beneficial arrangement. The investigators were able to demonstrate that the two predators seek each other’s company, spending more time together than expected by chance. They also found that groupers actively recruit moray eels through a curious head shake made close to the moray eel’s head to which the eel responds by leaving its crevice and joining the grouper. Groupers showed such recruitment more often when hungry.

Given that cooperative hunting increases capture success for each of the two predators, and that they don’t share with each other but swallow the prey whole, their behavior seems a form of “by-product mutualism,” defined as a form of cooperation in which both parties achieve rewards without sacrificing anything for the other. They are both out for their own gain, which they attain more easily together than alone.

The observed role division comes “naturally” to two predators with different hunting specializations, and is therefore far simpler to achieve than for members of the same species. Also, recruitment is quite common in the animal kingdom—for example, primates have specialized signals to solicit each other’s support in fights. What is truly spectacular about this study is that the entire interaction pattern—two actors who seemingly know what they are going to do and how this will benefit them—is not one we usually associate with fish. This is probably because we tend to develop cognitively demanding accounts for our own behavior and believe that absent the same cognition, the behavior simply cannot take place. It is very well possible, however, that our accounts overestimate the amount of intelligence that goes into complex behavior. Moreover, we have a tendency to underestimate the intelligence of animals at lower rungs of the evolutionary ladder.

In fact, it is the ladder idea itself that is wrong. The best way to approach animal intelligence is from an evolutionary and ecological perspective focused on the tasks that each species faces in nature. In this regard, these two reef predators show us that if it comes to survival, highly intelligent solutions are within the reach of animals as different from us as fish.Citation:

Citation: de Waal FBM (2006) Fishy Cooperation. PLoS Biol 4(12): e444 DOI: http://dx.doi.org/10.1371/journal.pbio.0040444


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Cite This Page:

Public Library of Science. "Fishy Cooperation: Scientists Discover Coordinated Hunting Between Groupers, Giant Moray Eels." ScienceDaily. ScienceDaily, 23 December 2006. <www.sciencedaily.com/releases/2006/12/061206095317.htm>.
Public Library of Science. (2006, December 23). Fishy Cooperation: Scientists Discover Coordinated Hunting Between Groupers, Giant Moray Eels. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2006/12/061206095317.htm
Public Library of Science. "Fishy Cooperation: Scientists Discover Coordinated Hunting Between Groupers, Giant Moray Eels." ScienceDaily. www.sciencedaily.com/releases/2006/12/061206095317.htm (accessed April 24, 2014).

Share This



More Plants & Animals News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Monkeys Are Better At Math Than We Thought, Study Shows

Monkeys Are Better At Math Than We Thought, Study Shows

Newsy (Apr. 23, 2014) A Harvard University study suggests monkeys can use symbols to perform basic math calculations. Video provided by Newsy
Powered by NewsLook.com
Raw: Leopard Bites Man in India

Raw: Leopard Bites Man in India

AP (Apr. 22, 2014) A leopard caused panic in the city of Chandrapur on Monday when it sprung from the roof of a house and charged at rescue workers. (April 22) Video provided by AP
Powered by NewsLook.com
Iowa College Finds Beauty in Bulldogs

Iowa College Finds Beauty in Bulldogs

AP (Apr. 22, 2014) Drake University hosts 35th annual Beautiful Bulldog Contest. (April 21) Video provided by AP
Powered by NewsLook.com
805-Pound Shark Caught Off The Coast Of Florida

805-Pound Shark Caught Off The Coast Of Florida

Newsy (Apr. 22, 2014) One Florida fisherman caught a 805-pound shark off the coast of Florida earlier this month. 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