Culture, lasting changes in a group that cannot be ascribed to genetic or ecological variation, is obviously a human quality, and it may be found in other vertebrates like some other primates and birds. A new computer simulation says it may be in fruit flies also.
Fruit flies can learn and copy the sexual preferences of their conspecifics after observing them copulating. For a behavioral pattern to be deemed culturally transmitted, there are considered:
1) the behavior must be learned socially, which is to say by observing conspecifics,
2) be copied from older individuals,
3) be memorized over the long term,
4) involve characteristics of individuals, such as their color, rather than the individuals themselves; and
5) be conformist, which is to say that the individuals learn the most common behavior in the population.
The team claim that fruit flies learning of sexual preferences among fruit flies meets all five criteria and say computer simulations show they possess all of the cognitive capacities needed to culturally transmit their sexual preferences across generations.
Two “observer” females watch a green male copulating with a “demonstrator” female, as a pink male is rejected. Credit: David Duneau/Science
Their simulations showed that those characteristics could lead to the emergence of long-lasting cultural traditions along transmission chains, in which the observers from one transmission step become the demonstrators for the ensuing transmission step. The authors compared their simulations with experimental transmission chains, and observed a perfect match between model predictions and experimental results. In addition, the researchers demonstrated the key role of conformism in fostering long-lasting local traditions.
Citation: Etienne Danchin, Sabine Nöbel, Arnaud Pocheville, Anne-Cecile Dagaeff, Léa Demay Mathilde Alphand, Sarah Ranty-Roby, Lara van Renssen, Magdalena Monier, Eva Gazagne, Mélanie Allain and Guillaume Isabel, 'Cultural flies: conformist social learning in fruit flies predicts long-lasting mate-choice traditions', Science, November 30, 2018. DOI : 10.1126/science.aat1590