Tag Archives: tadpoles

Dodging dots helps explain brain circuitry

In a new study, Brown University neuroscientists looked cell-by-cell at the brain circuitry that tadpoles, and possibly other animals, use to avoid collisions. The study produced a model of how individual inhibitory and excitatory neurons can work together to control a simple behavior.

PROVIDENCE, R.I. [Brown University] — A neuroscience study provides new insight into the primal brain circuits involved in collision avoidance, and perhaps a more general model of how neurons can participate in networks to process information and act on it. (more…)

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Cosmetic Chemical Hinders Brain Development in Tadpoles

*A new study finds that low concentrations of the chemical methylisothiazolinone has subtle but measurable negative effects on the neural development of tadpoles. The chemical is found in some cosmetics, although the study does not provide any evidence that cosmetics are unsafe for humans.*

PROVIDENCE, R.I. [Brown University] — Scientists, health officials, and manufacturers already know that a chemical preservative found in some products, including cosmetics, is harmful to people and animals in high concentrations, but a new Brown University study in tadpoles reports that it can also interrupt neurological development even in very low concentrations.

In the cosmetics industry, the biocide methylisothiazolinone or MIT, is considered safe at concentrations of less than 100 parts per million. Lab studies, however, have found that lower concentrations affected the growth of animal neurons. Picking up from there, the Brown researchers performed a series of experiments to investigate how 10 days of exposure at concentrations as low as 1.5 ppm would affect whole, living tadpoles as they develop. Their results appear in advance online in the journal Neuroscience. (more…)

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National Zoo and Partners First to Breed Critically Endangered Tree Frog

Although the La Loma tree frog, Hyloscirtus colymba, is notoriously difficult to care for in captivity, the rescue project is the first to successfully breed this species. Image credit: Brian Gratwice, Smithsonian's National Zoo

As frogs around the world continue to disappear—many killed by a rapidly spreading disease called chytridiomycosis, which attacks the skin cells of amphibians—one critically endangered species has received an encouraging boost. Although the La Loma tree frog, Hyloscirtus colymba, is notoriously difficult to care for in captivity, the Panama Amphibian Rescue and Conservation Project is the first to successfully breed this species.

“We are some of the first researchers to attempt to breed these animals into captivity and we have very little information about how to care for them,” said Brian Gratwicke, international coordinator for the project and a research biologist at the Smithsonian’s National Zoo, one of nine project partners. “We were warned that we might not be able to keep these frogs alive, but through a little bit of guesswork, attention to detail and collaboration with other husbandry experts—we’ve managed to breed them. The lessons we’re learning have put us on target to save this incredible species and our other priority species in Panama.”  (more…)

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