SAVE MONEY ON TRAVEL DEALS

The researchers said most prey immediately escape upon detecting a predator. However, when encountering resting predators, some prey approach and mob the predators despite any associated risk. And, while mobbing predators, the prey utter mobbing calls that have been suggested to vary depending on risk or predator category.

The new study from Uppsala University shows Siberian jay birds have evolved call systems that are as sophisticated as those of primates. The research also shows Siberian jays adjust their mobbing calls depending on both risk and predator category simultaneously.

"The chatter of mobbing jays is rather complex. The birds use over a dozen different calls, some of which are specific for owls and other for hawks, the two main predator categories of jays", Michael Griesser, who led the research, said. "My study supports the idea that the need to survive encounters with predators might have played an important role for the evolution of complex animal communication."

The research appears in the Proceedings of the Royal Society: Biological Sciences.

 BREAKING STORIES

Shocked skier crashes into elk

Rare strawberry preserved in seed vault

Vitamin D critical to fighting infections

Iceland votes on paying $5.2 billion debt

Secondhand smoke ups teen vessel damage

Advanced prostate cancer may boost suicide

'Interval training' good for older people

Woman has babies after ovary transplant

Overweight in middle age, greater decline

Iceland may become investigative haven

Hair sample reveals picture of ancient man

Sweden sending more troops to Afghanistan

Russia suspected of Swedish nuke dump

Suspect sues newspapers for libel

Stem cells aid nerve cells by contact

Gramp's fracture a warning to grandsons

Financing for Saab looks murky

Sweden to import wolves

Helicobacter pylori lingers in tissues

Report: GM has deal with Spyker for Saab