Do Père David's deer lose memories of their ancestral predators?

• Published in: PloS one Vol. 6; no. 8; p. e23623
• Main Authors: Li, Chunwang, Yang, Xiaobo, Ding, Yuhua, Zhang, Linyuan, Fang, Hongxia, Tang, Songhua, Jiang, Zhigang
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 24.08.2011; Public Library of Science (PLoS)
• Subjects: Acoustics; Animal behavior; Animals; Anti-predator behavior; Biology; Conservation biology; Deer; Deer - physiology; Dogs; Ecology; Elaphurus davidianus; Female; Foraging behavior; Foraging habitats; Game theory; Hypotheses; Laboratory animals; Male; Memory - physiology; Models, Biological; Playbacks; Population; Predation; Predators; Predatory Behavior - physiology; Prey; Sound; Studies; Tape Recording; Visual stimuli; Vocalization, Animal - physiology; Wolves; Zoology; Beijing China; New York; California; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0023623

Whether prey retains antipredator behavior after a long period of predator relaxation is an important question in predator-prey evolution. Père David's deer have been raised in enclosures for more than 1200 years and this isolation provides an opportunity to study whether Père David's deer still respond to the cues of their ancestral predators or to novel predators. We played back the sounds of crows (familiar sound) and domestic dogs (familiar non-predators), of tigers and wolves (ancestral predators), and of lions (potential naïve predator) to Père David's deer in paddocks, and blank sounds to the control group, and videoed the behavior of the deer during the experiment. We also showed life-size photo models of dog, leopard, bear, tiger, wolf, and lion to the deer and video taped their responses after seeing these models. Père David's deer stared at and approached the hidden loudspeaker when they heard the roars of tiger or lion. The deer listened to tiger roars longer, approached to tiger roars more and spent more time staring at the tiger model. The stags were also found to forage less in the trials of tiger roars than that of other sound playbacks. Additionally, it took longer for the deer to restore their normal behavior after they heard tiger roars, which was longer than that after the trial of other sound playbacks. Moreover, the deer were only found to walk away after hearing the sounds of tiger and wolf. Therefore, the tiger was probably the main predator for Père David's deer in ancient time. Our study implies that Père David's deer still retain the memories of the acoustic and visual cues of their ancestral predators in spite of the long term isolation from natural habitat.