The following includes an excerpt which was attached to the Wikipedia page “Vampire Bat” (http://en.wikipedia.org/wiki/Vampire_bat). The first and last sentence in this excerpt come directly from previous Wikipedia information and are used solely as a reference to identify what was added.
…This has been noted by many naturalists as an example of reciprocal altruism in nature.
It was previously thought that food sharing depended equally on relatedness and reciprocation.[i] However, it has recently been discovered that the predictive capacity of reciprocity surpasses that of relatedness.[ii] This finding suggests that vampire bats are capable of preferentially aiding their relatives, but that they may benefit more from forming reciprocal, cooperative relationships with relatives and non-relatives alike.[ii] Furthermore, a recent study demonstrated that donor bats were more likely to approach starving bats and initiate the food sharing. These findings contradict the harassment hypothesis—which claims that individuals share food in order to limit harassment by begging individuals.[ii] All considered, vampire bat research should be interpreted cautiously as much of the evidence is correlational and still requires further testing.[iii] For example, researchers question vampire bats’ ability to identify kin when past association, or interaction, is controlled.[iii] Similarly, scientists question if bats modify investments based on how other bats cooperate.[iii]
Another ability that some vampire bats possess is identifying and monitoring the positions of conspecifics (individuals of the same species) simply by antiphonal calling.[iv] Antiphonal calling is simply a song or verse sung in response.
Vampire bats also engage in social grooming…
[i] Wilkinson, G. S. (1984). “Reciprocal food sharing in the vampire bat”. Nature 308: 181-184. doi: 10.1038/308181a0
[ii] Carter, G. G., & Wilkinson, G. S. (2013). “Food sharing in vampire bats: reciprocal help predicts donations more than relatedness or harassment”. Proc R Soc B 280: 20122573. doi: 10.1098/rspb.2012.2573
[iii] Carter, G., & Wilkinson, G. (2013). “Does food sharing in vampire bats demonstrate reciprocity?”. Communicative and Integrative Biology 6(6): e25783. doi: 10.4161/cib.25783
[iv] Carter, G. G., Fenton, M. B., & Faure, P. A. (2009). “White-winged vampire bats (Diaemus youngi) exchange contact calls”. NRC Research Press 87: 604–608. doi: 10.1139/Z09-051
Tags: bats, communication, cooperation, kin selection