Thursday Colorful photo_challenge Bluetit and berry

A recent study found an association between a female blue tit with several male birds for the purpose of protecting offspring from predatory attacks. The unique behavior was successfully expressed by scientists from
Behavior of female birds that sometimes paired with more than one stud actually long been observed by scientists, especially since 1990. But all has not been discussed the motivation of female birds do the practice.

Why do female birds practice polyandry? The question is what disturbs the attention of scientists from the University of Bergen, Norway to examine the motives of female birds do polyandry. In this case they use blue tit as the object of his research.
In general the blue tit begins to pair in the winter, At that time the blue tit females will build the nest alone without the help of male birds. New male and female breeds work together when saplings begin to hatch. Both will care for and feed their children.

But the results of DNA testing of the birds that are in one nest revealing something new, Some puppies turned out to come from different males. That is, the female mates with more than a male.
The study also found another fact that the nest containing the different breeds of the father had a small chance of being attacked by predators, because the nest will always be surrounded and supervised by several adult male birds who are always on guard.

Researchers assume some male birds are always watching the nest because they have the potential to have offspring in the nest.
Young birds with different fathers are likely to be descendants of other males in the area. When the female is incubating and caring for her children the males work together to monitor and warn of intruders.

saplings from one heredity turned out to have a greater risk of being attacked by predators rather than birds from some males. the reason the males will work together is when they know there is a danger of threatening their offspring.