Having specific roles in the family is not only applicable to humans. Penguins share the same setup too, with theirs appearing to be much more rigid that it makes them even more vulnerable to climate change.
A new study has found that the fixed division of labor among penguin parents may subject its offsprings to food shortages. This is because the species are not able to adapt to the imminent occurrence of climate change, which entails environmental situations that cause lack of food.
A concept called behavioral plasticity may allow species to adapt to food shortages due to climate change. This then encourages them to thrive and grow more in population.
"Conversely, inflexible parental roles may constrain sex-specific parental investment and amplify reduced reproductive fitness during nutritional stress," the authors write.
To find out the impacts of food shortages due to climate change among penguins, researchers observed Eastern Rockhopper (Eudyptes) penguins during two seasons. The first one was in 2011, when there were abundant food and the second was in 2012, when there was deficient food supply.
The researchers have observed how the chicks were fed, measured the chicks' weight at one month old and the general success of raising chicks.
The authors also recorded how much time the penguin parents spend with and away its offsprings. They did this by installing a narrow pathway from the sea to the nest.
The results of the study have shown that parents were able to take care of chicks more in 2011 than in 2012.
In 2012, the male penguins spent more time out to the sea to forage and make up for the body mass it lost during rearing duties. This lessens the time of the male penguins to bring food home to its chicks. As a result, the chicks grew slower during this period.
Conventional Parent Penguin Roles
Penguin parents have two primary roles: feed and safeguard its young.
During guarding duties, parents fast and let go of sea trips to look for food. Although penguin species alternate guarding and rearing responsibilities, seven species of Eudyptes penguins do not follow this.
Males guard chicks during the first three to four weeks of egg hatching, while females go out to eat and find food for the family.
In the next six weeks, the family practices a "daycare" setup wherein chicks are placed in crèches and parents take turns in feeding. Both parents may also extend its sea trips to forage during this period.
Climate Change Implications
The study shows that the very rigid gender roles between penguins may not be appropriate to ensure that chicks are nourished as needed. This setup may have particular setbacks during seasons of poor food supply.
Experts say changing these practices and dividing guarding and foraging duties equally may increase chicks' food intake by up to 34.5 percent. However, it is easier said than done. For one, females are less aggressive at guarding thus; it may not be too wise to give the same amount of protective duties to both males and females.
The study was published in the journal Behavioral Ecology and Sociobiology on Tuesday, Feb. 9.
Photo: Liam Quinn | Flickr
