No Ears, No Problem: Frogs Can Hear With Their Lungs

TL;DR

Frogs use their lungs and tympanic membranes to hear, with the lungs playing a crucial role in picking up low-frequency sounds.

Transcript

Today’s episode is sponsored by Brilliant. Go to Brilliant.org/SciShow to check out their course on waves and light. [ ♪INTRO ] Frogs often have a lot to say. Just ask the residents of the Big Island of Hawai'i, who get serenaded by tiny, invasive coqui frogs every night. But if you’ve ever looked at a frog’s head, you might have noticed that they ... Read More

Key Insights

• 👂 Frogs rely on their tympanic membranes to hear, which vibrate in response to sound waves.
• 🙃 The location of the sound source can be determined by the pressure difference on both sides of the tympanic membranes.
• 😘 Some frogs have small tympanic membranes that cannot respond to low-frequency sounds effectively.
• 🫁 The lungs of frogs can pick up low-frequency sounds that the tympanic membranes cannot capture, and in some species, the lungs replace the function of the membranes entirely.
• 🥰 Research suggests that the ability to hear through the body, including the lungs, might have been an ancestral trait for amphibians.
• 🦻 Understanding frog hearing can provide insights into the evolution of auditory systems.
• 💍 Brilliant.org offers engaging STEM courses, including a "Waves and Light" course that delves into the science behind noise-canceling headphones.

Questions & Answers

Q: How do frogs hear without external ears?

Frogs rely on tympanic membranes on their heads, which vibrate when sound waves hit them. The vibrations trigger cells in the inner ear, sending electrical signals to the brain for processing.

Q: How do female frogs locate the source of a sound?

Female frogs use the differences in pressure on both sides of their tympanic membranes to determine the direction of a sound. The membrane on the side the sound came from experiences greater pressure.

Q: Why can't some frogs hear low-frequency sounds?

Some frogs, like the coqui frog, have small tympanic membranes that are unable to respond to low-pitched sounds. These lower-frequency sounds carry less energy, which the small membranes cannot capture effectively.

Q: How do the lungs help frogs hear?

The lungs of frogs can vibrate like a giant eardrum when sound waves pass through them. The vibrations are then transmitted to the mouth, using the eustachian tubes, to reach the tympanic membranes from the inside.

Summary & Key Takeaways

• Frogs don't have external ears but rely on their tympanic membranes on their heads to hear. Sound waves vibrate the membranes, which then send electrical signals to the auditory center of the brain.

• The tympanic membranes also help female frogs locate the source of a sound, as the pressure difference between both sides of the membrane indicates where the sound came from.

• Some frogs, like the coqui frog, have small tympanic membranes that are unable to respond to low-frequency sounds. However, their lungs can pick up these sounds and replace the function of the membranes entirely in some species.