Manipulative Mothers Make for Adventuresome Magpies

If you've ever had the fortune to watch a clutch of magpie chicks hatch, you may quickly come to realize that the oldest females are the most fun to watch. They are frequently more curious, energetic and adventuresome than their brothers.

Now researchers are suggesting that mother magpies may intentionally tweak the early personalities of their chicks in order to fit into specific environments.

According to a study recently published in the journal Behavioral Processes, the order in which magpie eggs are laid can strikingly determine what kind of personality the chicks emerge with. This is most clearly illustrated in female magpies, who show that first hatched females are more explorative than their male counterparts, but last hatched females are meeker compared to their brothers.

This was discovered after a series of novel tests involving new environments and objects, conducted by researchers from the University of Jyväskylä, Finland, and the University of Lincoln in the UK.

The results suggest that hormonal and post-natal environmental mechanisms could be the sole determinants of early chick personality - a rather disturbing thought if the same applies for humans.

"Previous research has shown that exposure to hormones during early development is important in shaping the development and personality traits of the offspring," researcher Carl Soulsbury explained in a recent release. "Understanding which hormones act as drivers for this variation is a key aspect of future study."

The study details how yolk androgens - the hormone that controls the development of male characteristics - are distinct drivers of personality. And typically, these hormones actually increase in concentration with each consequent egg lay.

"The fact that observable differences between the first hatched and last hatched magpie's behaviors exist indicates that mothers may be able to produce variable traits, possibly through adjustable transmission of maternal hormones or creating the conditions for sibling rivalry," said Souldbury. "Mothers could potentially produce a variety of personalities perhaps as an adaptive strategy in unpredictable environmental conditions. We found consistent variation in exploration and neophobic behavior of the magpie related to both date of hatching, sex and hatching order."

He goes on to add that the danger of an environment may then determine in what order a mother magpie may aim to lay and help hatch her eggs.

Nature World News recently reported on a similar natural phenomenon, in which the environment of an ant colony appears to almost exclusively determine its collective boldness.