What comes to mind when you think about communication between frogs? The typical “ribbit” sound might play in your head. However, researchers at Boston University have discovered a more unique mode of communication. Red-eyed treefrogs use vibrations as signals in aggressive interactions.
During breeding, each male treefrog defends a calling site that is at minimum 0.5 meters away from another male’s territory. Competition over females may cause a male to lift himself off the plant and subsequently contract and extend his hind limbs. His lower body shakes during this tremulation display, and vibrations are sent through the plant. Researchers sought to mimic these calls using a robotic frog and an electrodynamic shaker in playback experiments. Males responded with their own tremulation displays, and the characteristics of the vibrations varied depending on the size of the male and context. Consequently, the signals encode information about the aggression and status of the signaler. The visual playbacks also elicited the strongest response from males, showing that multiple modes of signaling are essential in aggressive interactions. Researchers even discovered that the vocalizations of treefrogs can create vibrations in plants and carry additional information to the receiver.
An author of the research article remarks that this behavior is quite frequent, but humans have tended to neglect vibrations as a possible mode of communication. Furthermore, previous studies had used white light when observing the frogs. Infrared light was instead used in these experiments and the disturbance was therefore reduced. Researchers were able to view a wider range of behaviors, contributing to a more complete ethogram of aggressive interactions between males.
We now know that there is more to frogs than the typical “ribbit” sound they produce. Additionally, discovery of vibrations has opened up new avenues in research regarding other species. Researchers believe that this form of communication could be common among many arboreal vertebrates, including birds, lizards, and primates. Consequently, numerous aspects of animal communication remain unknown to humans.
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Posted by Katie Kalutkiewicz
It is crazy how many communication methods are undetected to the human eye. It seems this research has opened the door for a lot more research to be done. Do the researchers know if the vibrations are used to communicate different information then the vocal ribbit? Also, is the combination of communication methods only effective for aggressive signals?
ReplyDeletePosted by: Sara Weaver
This reminds me of the caterpillar vibration signaling we saw in class. It's cool that tree frogs do something similar and definitely seems likely that more species also use this form of communication. Can you elaborate about how white light was interfering with their displays?
ReplyDelete-Alex Sprague
This does sound similar to the caterpillars from class! Also, the researchers are not sure whether vibrations and vocal communication are used to communicate different information. However, they have concluded that differences exist between vibrations and visual signals. Frogs did not respond to visual-only playbacks, indicating that the vibrations carry information that is not present visually.
ReplyDeletePosted by Katie Kalutkiewicz
The technology involved in experiments such as these is so cool!
ReplyDeleteIt is interesting to know that frogs use different modes of communication. I wonder if any frogs use their "ribbits" to lie to potential mates and give false information about their size and status.
-Meghan Nichols
Do you know if the ethogram of behaviors of the frogs contains details about the similarities in the frequency and length of the vibrations..or is this research yet to be conducted?
ReplyDeleteahmed sandakli