- Pumpkin toddlers are very bad at jumping, often losing balance in mid-air and crashing awkwardly.
- Researchers have determined that this is due to the shape of their inner ear canals, the area of the body that controls balance and orientation: their semicircular ear canals are the smallest recorded in vertebrates.
- Toadlets live in the leaf litter of the Atlantic forest of Brazil, where being small enough for burial is an advantage.
- But frogs are so small that the balance mechanism in their ears can’t respond to quick movements, resulting in some outrageous movements.
Frogs usually land on their feet, but a group of small Brazilian toadlets are so small that they cannot make a landing.
Pumpkin Todlet (brachycephalus spp.) are juveniles, about the size of an M&M. These small frogs jump when nudged or intimidated, but lose their balance as they drop into the air, often landing with a graceless thud on their back, abdomen or wherever they fall.
“They are not great jumpers, and they are not particularly good walkers either,” Edward Stanley, director of the Florida Museum of Natural History’s Digital Discovery and Dissemination Laboratory, said in a statement. “They stomp around in a paused, peg-like version of walking.”
Researchers found that this clumsy jump is related to the part of the inner ear that controls balance. When frogs (and many other animals) move, fluid flows over microscopic hairs inside the spiral chambers of the inner ear. As they move, these hairs trigger electrical impulses in the brain that tell the animal how to differentiate from below, balance, and keep its body upright.
However, because toadlets are so small, these fluid-filled chambers do not send a signal strong enough to help the frog expel it during its daring jump. According to a newly published study in the journal, Pumpkin Toadlets, it turns out to have the smallest semicircular ear canals recorded in any vertebrate animal. scientific progress.
Stanley, a co-author of could.” the study.
Scientists say miniature frogs have traded balance for stature (or lack thereof). Their wee bodies can easily nest in the leaf litter of the forest floor in the tropical Atlantic Forest of Brazil, where they live.
some brachycephalus are brightly colored, which is a warning to potential predators that they are poisonous. Others use camouflage mimicking the brown and black colors of their leafy surroundings. Either way, toddlers stand their ground and hold on, rather than attempting any sudden moves in the face of danger, or attraction.
“They’re not jumping around a lot, and when they do, they probably aren’t worried about landing, because they’re doing it in frustration,” said study co-author André Confetti, a PHD. Candidate at the Federal University of Paraná, Brazil. “They gain more from being small than they lose from their inability to stick to the landing.”
Scientists uncovered frogs’ tiny semicircular canals via Ovart, a four-year project involving 18 institutions to create 3D models from CT scans for more than 20,000 museum specimens across the US , Four species of pumpkin toadlets were included in the project.
A 2017 study found that at least two species of brachycephalus Frogs have underdeveloped auditory systems, making them deaf to the high-pitched mating calls of admiring males. This smaller system may be another trade-off for their small size.
one of the species, brachycephalus ephipiumIt has attracted a lot of attention over the years when scientists discovered that its bones glowed through their skin under UV light. They may be using it as a visual signal for mating, as they are deaf to their own love songs.
“They are strange frogs,” said Confetti. “They can’t swim, they don’t have tadpoles, and they don’t seem to get along very much. We monitored the acoustic behavior of these frogs and recorded the same individuals in the same location over the course of a year. are capable of.”
The only “place” for the pumpkin toad is in the Atlantic Forest of Brazil, one of the most endangered forests on the planet. After large-scale clearing for soy and sugarcane farming and animal husbandry that began in the 1940s, only about 3.5% of its primary forest remains. Fortunately, many pumpkin toadlets still thrive in a network of protected areas, where they can move safely, undisturbed.
banner image: Pumpkin toadlets live in the leaf litter of the Atlantic forest of Brazil, where being small is an advantage. Image by Carol Manzano (CC BY-SA 4.0) via Wikimedia Commons.
Citation:
Essner, RL, Pereira, RE, Blackburn, DC, Singh, AL, Stanley, EL, Moura, MO, … Pie, MR (2022). The shape of the semicircular canal inhibits vestibular function in small frogs. science advance, 8(24). DOI: 10.1126/sciadv.abn1104
Gaute, S., Mason, M. J., Christensen-Dulsgaard, J., Montealegre-Z., F., Chivers, B. D., Sarria-S, F. A., … Felipe Toledo, L. (2017). Evidence of auditory insensitivity to vowel frequency in two frogs. scientific report, 7(1), 1-9. doi:10.1038/s41598-017-12145-5
Goutte, S., Mason, M. J., Antoniazzi, M. M., Jared, C., Merle, D., Kees, L., … Thauri, M. . (2019). Intense bone fluorescence reveals hidden patterns in pumpkin toadlets. scientific report, 9(1). doi:10.1038/s41598-019-41959-8
