Study
Reciprocal food sharing in the vampire bat
Wilkinson, Gerald S.
Nature, 1984
Marked vampire bats in Costa Rican roosts were observed over years, recording who regurgitated blood to whom, alongside genetic relatedness and how often individuals roosted together.
- Studied in
- Desmodus rotundus
- Sample size
- 110 observed regurgitation events among marked wild bats
Bats regurgitated blood to unrelated roost-mates as well as to kin, and the strongest predictor of a donation was how often the two bats had associated — and whether the recipient had previously fed the donor.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Food sharing in vampire bats is consistent with reciprocal altruism, sustained by repeated association and individual recognition.
How NatureHQ reads it
Vampire bats matter to this debate because the stakes are unusually legible: a bat that misses two consecutive nights of feeding dies, so a donation is measurably costly and a repayment measurably valuable. The 1984 result was contested for years on the grounds that kinship and association are hard to separate in a roost. The later controlled work is what settled it.
- Relatedness and association are correlated in wild roosts, making their contributions hard to separate observationally.
- Regurgitation events are rare and observation is necessarily incomplete.
- One species with an unusually extreme starvation risk; the finding may not generalise to other bats.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Nature PortfolioPublished in a Nature Portfolio journal.
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-09.