Those who help each other can invade harsher environments

Date: February 20, 2017

Source: Lund University

Through cooperation, animals are able to colonize harsher living environments that would otherwise be inaccessible, according to a new study from Lund University in Sweden, together with researchers in England and USA. The research community has long believed this was the other way around -- that species in tough environments had to cooperate to survive. As a result the established view of why animals cooperate is turned upside-down.

Some species of birds cooperate closely in the rearing of offspring. The older siblings appear to selflessly help their parents rear the youngest brood. This phenomenon is most common in species that live in harsh environments, where the climate is hot and rain is scarce.

For a long time, researchers believed that the harsh conditions have forced individuals to help because they can't breed on their own. It seems, however, the opposite is true -- that the cooperation evolves first, and this gives species a chance of successfully invading and surviving in more barren places.

"Cooperation appears to be an important prerequisite to colonization of arid habitats," says Charlie Cornwallis, biologist at the Faculty of Science at Lund University.

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I've got your back: Fish really do look after their mates

Date:September 25, 2015

Source:ARC Centre of Excellence in Coral Reef Studies

When it comes to helping each other out, it turns out that some fish are better at it than previously thought.

New research from the ARC Centre of Excellence for Coral Reef Studies at James Cook University has found that pairs of rabbitfishes will cooperate and support each other while feeding.

While such behaviour has been documented for highly social birds and mammals, it has previously been believed to be impossible for fishes.

"We found that rabbitfish pairs coordinate their vigilance activity quite strictly, thereby providing safety for their foraging partner," says Dr Simon Brandl from the ARC Centre of Excellence for Coral Reef Studies.

"In other words, one partner stays 'on guard' while the other feeds -- these fishes literally watch each others' back," Dr Brandl says.

"This behaviour is so far unique among fishes and appears to be based on reciprocal cooperation between pair members."

Continued ...

'Leaders and lifters' help ants move massive meals

By Jonathan Webb

Science reporter, BBC News

29 July 2015 

From the section Science & Environment

Scientists in Israel have discovered how ants co-operate to move big chunks of food back to their nests.

A large team of ants does the heavy lifting but they lack direction, while a small number of "scouts" intervene and steer for short periods.

They appear to have a mathematically perfect balance between individuality and conformism, the researchers said.

The discovery was made by analysing videos of ants carrying oversized food items, including Cheerios.

Published in the journal Nature Communications, the study used a very common species known as the longhorn crazy ant.

The only communication in the system is the forces that they feel through the objectDr Ofer Feinerman, Weizmann Institute of Science

The species' name refers to the way the little creatures dash about, frequently changing direction with apparently aimless abandon.

But the new findings suggest that the level of aimlessness in these ants' behaviour is in fact very finely tuned.

Pushy scouts

"The group is tuned to be maximally sensitive to the leader ants," said the paper's senior author Dr Ofer Feinerman, a physicist at the Weizmann Institute of Science in Rehovot.

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How Cooperation Can Trump Competition in Monkeys

ScienceDaily (July 4, 2012) — Being the top dog -- or, in this case, the top gelada monkey -- is even better if the alpha male is willing to concede at times to subordinates, according to a study by researchers from the University of Pennsylvania, the University of Michigan and Duke University.

Alpha male geladas who allowed subordinate competitors into their group had a longer tenure as leader, resulting in an average of three more offspring each during their lifetimes.

The findings, collected from data during a five-year period ending in January 2011 through the University of Michigan Gelada Research Project, were published in the Proceedings of The Royal Society.

The research was conducted by Noah Snyder-Mackler, then a graduate student in the Department of Psychology in Penn's School of Arts and Sciences. He collaborated with Thore Bergman, assistant professor of psychology at Michigan, and Susan Alberts, professor of biology at Duke.

Cooperation is surprisingly common among wild animals, the researchers said. While it makes evolutionary sense for animals to help their kin, it is harder to explain cases where competitors -- especially unrelated adult males -- join forces. This conundrum is particularly hard to explain because mating is generally a zero-sum game in which males can only reproduce by stealing mating opportunities from each other.

Continued:  http://www.sciencedaily.com/releases/2012/07/120704021831.htm