Various species and subspecies of canids (wolves, coyotes, etc.) have distinguishing repertoires of howling, according to a team of scientists who analyzed a database of over 2,000 canid howls.
Two wolves. Image credit: Monty Sloan.
The team, headed by Dr. Arik Kershenbaum of the University of Cambridge, investigated the nature of variation in howls across 13 species and subspecies of canids.
The scientists made use of howls recorded from both captive and wild animals, from Australia and India, to Europe and the United States, creating a database of 6,000 howls that was whittled down to 2,000 for the study.
They used computer algorithms, distilling different howls into 21 howl types based on pitch and fluctuation, and then matching up patterns of howling.
They found that the frequency with which types of howls are used — from flat to highly modulated — corresponded to the species of canid, whether dog or coyote, as well as to the subspecies of wolf.
For example, the howling repertoire of the gray wolf (Canis lupus) is heavy with low, flat howls but doesn’t feature the high, looping vocal that is the most frequently used in the range of howls deployed by rare red wolves (Canis rufus).
“These distinctive howl repertoires resemble vocal dialects, with each species having its own identifiable use of the various howl types,” said Dr. Kershenbaum, first author on a study published in the journal Behavioural Processes.
“The findings could be used to track and manage wild wolf populations better, and help mitigate conflict with farmers.”
According to Dr. Kershenbaum’s team, the origins of language development in humans are mysterious, as the vocalizations of our closest existing biological relatives such as chimpanzees are relatively simple.
“Studying the sounds of other intelligent species that use vocal communication for cooperative behavior — such as wolves and dolphins — may provide clues to the earliest evolution of our own use of language,” the researchers said.
“Wolves may not be close to us taxonomically, but ecologically their behavior in a social structure is remarkably close to that of humans,” Dr. Kershenbaum added.
“That’s why we domesticated dogs — they are very similar to us.”
“Understanding the communication of existing social species is essential to uncovering the evolutionary trajectories that led to more complex communication in the past, eventually leading to our own linguistic ability,” the scientist said.
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Arik Kershenbaum et al. 2016. Disentangling canid howls across multiple species and subspecies: Structure in a complex communication channel. Behavioural Processes, vol. 124, pp. 149-157; doi: 10.1016/j.beproc.2016.01.006
