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Common vampire bats form enduring social bonds and may regurgitate blood meals to hungry roost-mates, including non-relatives who have shared before.

Common vampire bat

NatureBiologyHealth

The story behind the card

A vampire bat that fails to feed can starve within about two to three nights, so a shared meal can be the difference between life and death. The biologist Gerald Wilkinson described the sharing in detail in 1984, from wild bats in Costa Rica, and showed that bats tend to feed those that have fed them before, a rare mammal example of reciprocal help between non-relatives. Later studies led by Gerald Carter found that new partnerships grow step by step, starting with grooming before any blood is shared. In a 2019 study, bats that had formed bonds while housed together in captivity kept many of those bonds after release into the wild, where they were tracked with tiny proximity sensors.

Türkçe oku
Bayağı vampir yarasalar uzun süren dostluklar kurar. Aç kalan bir tünek arkadaşına, akrabası olmasa bile, daha önce kendisiyle paylaşmışsa emdiği kanın bir kısmını kusarak verebilir.

Beslenemeyen bir vampir yarasa iki üç gece içinde açlıktan ölebilir; bu yüzden paylaşılan bir öğün hayat kurtarır. Biyolog Gerald Wilkinson bu paylaşımı 1984'te Kosta Rika'daki yabani yarasalarda ayrıntılı olarak anlattı. Yarasaların, daha önce kendilerini doyuranları doyurmaya daha yatkın olduğunu gösterdi; bu, memelilerde akraba olmayanlar arasındaki karşılıklı yardımın ender örneklerinden biridir. Gerald Carter'ın yürüttüğü sonraki çalışmalar, yeni ortaklıkların adım adım kurulduğunu ortaya koydu: yarasalar önce birbirini tımar ediyor, kan paylaşımı ancak sonra geliyor. 2019'da yayımlanan bir araştırmada, laboratuvarda bir arada tutulurken bağ kuran yarasalar doğaya bırakıldıktan sonra bu bağların çoğunu sürdürdü; hayvanlar minik yakınlık sensörleriyle izlendi.

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