SCIENCE LAB SCAMPER : SMALL SINGERS [2]

 

Because Brachycephalus frogs are so small, some species look very similar and can't be distinguished by sight alone.

Yet scientists have found that their mating calls are distinct enough so females will be attracted to males of the correct species, and even an inexperienced human listener can hear the differences.

'' You immediately know that they are different sounds,'' said Dr. Toledo, who described the B, dacnis mating call as shorter, with fewer notes, soft in volume and chirpy in sound.

'' People usually think it's a cricket, not a frog.''

DNA tests provided confirmation that B. dacnis is genetically different from other species in its group.

This makes it the seventh flea-toad species known to science, and the second - smallest vertebrate species known on the planet.

One specimen found from another Brachycephalus frog is slightly smaller, at 6.5 millimeters.  

These differences are almost imperceptible, according to Dr. Toledo, and based merely on what specimens have been recorded so far - scientists could soon find a specimen of the new B. dacnis species that is just as small.

Before these discoveries, the record for the smallest vertebrate was held by the New Guinea Amau frog, at seven millimeters long, and a freshwater dwarf goby fish, at 7.9 millimeters. [ Sophia Quaglia ]