In a new study from The Royal Society, scientists have discovered many mammals use sounds that don’t match their body size. For example, dolphins’ vocal patterns sound much higher than would be expected for an animal of their larger size. However, red deer produce vocal patterns that are much lower than would be expected for their smaller size. 

Different calls have also set up a new determining characteristic on whether a species is a vocal learner: species who are signaling higher vocalizations relative to their size are most likely evolving linguistically. 

These inconsistencies are contributing to the study of human linguistics as well as the study of animals and vocal learning. By determining why animals are changing their vocal tones, scientists can help pin down our own linguistic history as well as understand the evolution of highly communicative animal species. 

What is Vocal Learning

Vocal learning is the process animals go through as they mirror each other’s communication styles and learn to communicate using their voice. Birds are one of the most common animals known for vocal learning. 

For example, wrens and goldfinches have songs that are tonally similar. Research suggests that this is because one bird developed a vocal communication style first. The other began to mimic it. As natural selection ran its course, the two species’ communication styles melded and the birds who could communicate were the ones who survived. 

The same thing is happening with dolphins according to The Royal Society’s new study. Dolphins who can hit higher notes are the dolphins that are more adept at communication. Communication is key to survival. 

This study is important because it shows the difference in vocal learning between animals, like dolphins, who are evolving linguistically, and animals, like red deer who are using dishonest signalling. 

What is Dishonest Signaling?

Red deer use dishonest signalling when they use vocalizations that make them sound larger than they actually are. Why do they do this? For reproductive purposes. A larger deer is more likely to mate and reproduce so sounding larger fares well for their survival. 

Dishonest signaling has also been observed in non-poisonous frogs. Non-poisonous frogs will sometimes mimic the sounds of other poisonous amphibians to dissuade a potential predator. Again, this type of dishonest signaling is a survival tactic. 

The difference between red deer and non-poisonous frogs compared to dolphins is their use of vocalizations. Dolphins are a vocal learning species that ultimately uses its vocals to communicate linguistically, much like humans. 

Red deer and frogs are communicating solely for survival. 

Why is this important? 

By differentiating between species that are vocal learners and ones that merely vocalize, scientists can better understand how animals communicate, their linguistic development, and our own linguistic evolution. 

Scientists can also create a framework for determining which species may eventually develop linguistically via vocal learning by listening to their calls. For example, manatees have developed much higher toned calls, yet have not before shown any signs of vocal learning. Could manatees be next on Mother Nature’s list of linguistically inclined creatures?

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