Scientists discover rare tree frogs long thought extinct

NEW DELHI -- For more than a century, two mysterious tree frog specimens collected by a British naturalist in 1870 and housed at the Natural History Museum in London were assumed to be part of a vanished species, never again found in the wild.

See Full Article

Until now.

A group of scientists, led by renowned Indian biologist Sathyabhama Das Biju, has rediscovered the frogs and also identified them as part of a new genus -- one step higher than a species on the taxonomic ranking. Not only have they found the frogs in abundance in northeast Indian jungles, they believe they could also be living across a wide swathe of Asia from China to Thailand.

"This is an exciting find, but it doesn't mean the frogs are safe," Biju said, adding that he hopes the discovery leads to more awareness of the dangers of unfettered development to the animals. The frogs were found at high altitudes in four northeast Indian states, underlining the rain-soaked region's role as a biodiversity hotspot.

Some of the forest areas where Biju's team collected frogs in 2007 and 2008 were already slashed and burned by 2014 for agricultural development. The region's tropical forests are quickly disappearing because of programs to cut trees, plant rice, expand human settlements and build roads.

Industrial growth amid a decade-long economic boom has also increased pollution, to which frogs are particularly vulnerable. That same sensitivity to climate and water quality makes them perfect environmental barometers, putting them at risk when ecological systems go awry. Of the more than 7,000 amphibian species known globally, about 32 per cent are threatened with extinction, according to the International Union for Conservation of Nature.

"This frog is facing extreme stress in these areas, and could be pushed to extinction simply from habitat loss," Biju said. "We're lucky in a way to have found it before that happens, but we're all worried."

Finding the frogs was an accident. The team had been searching the forest floor for other amphibians in 2007 when, one night, "we heard a full musical orchestra coming from the tree tops. It was magical. Of course we had to investigate," Biju said.

For the study of the new frog genus, Frankixalus, published Wednesday by the Public Library of Science journal PLOS ONE, Biju and his doctoral students teamed up with researchers from the central Indian state of Pune, Sri Lanka, Brussels and the American Museum of Natural History.

They looked at the frogs' behaviour, collected specimens and described their outer appearance and skeletal features. But it wasn't until they had sequenced the frogs' genetic code that they confirmed it as a new genus, and surprisingly found another DNA match from a single tadpole specimen reported recently under a mistaken identity in China.

The frogs had long been considered lost to science, with the first -- and only -- previously known specimens collected in 1870 by British naturalist T.C. Jerdon in the forests of Darjeeling. Over decades, the frogs were reclassified at least four times in cases of incorrect identity as scientists drew conclusions from their enlarged snouts or the webbing between their toes.

Biju believes the frogs remained hidden from science so long because of their secretive lifestyle living in tree holes at heights up to 6 metres (20 feet) above ground. Most tree frogs actually live in shrubs or tree holes closer to the ground. But other experts suggest that, while the uniquely high habitat does make them hard to find, the frogs probably remained in obscurity simply because there are so few scientists working in the remote region.

"This part of Southeast Asia, in particular, is poorly inventoried," said James Hanken, a biology professor and director of the Museum of Comparative Zoology at Harvard University. Given the habitat threats and alarming rate of extinctions worldwide, he said the "remarkable" tree frog find "points out that we may be losing even more species than we know or can fully document."

"It doesn't in any way offset the tragic losses represented by global amphibian extinction," said Hanken, who was not involved in the tree frog study.

Biju's team named the new frog genus Frankixalus after herpetologist Franky Bossuyt, who was Biju's adviser when he was a student at the Vrije Universiteit in Brussels. Only two species within the genus have been identified, including the Frankixalus jeronii first described in the 19th century. The scientists are still trying to confirm whether a second collected species was mistakenly named within another genus of tree frogs. There are now 18 tree frog genera known worldwide.

The study documents the tree frogs' unusual maternal behaviour, with the females laying fertilized eggs in a tree hole filled with water, and then returning at regular intervals after the tadpoles hatch to feed them with unfertilized eggs.

"This is incredible," Biju said, excitedly dumping a pile of pickled tadpoles onto a glass-covered table in his office at the University of Delhi, and selecting one to place under a microscope. The magnification reveals a clutch of undigested eggs still inside the tadpole's belly. "Do you see these eggs? Just imagine, the mother is coming back over and over and dropping these eggs for her babies to eat."

Rather than nascent teeth, the tadpoles have smooth, suction-like mouths to pull in the eggs. Their eyes are positioned on the top of their heads, rather than on the sides. Biju suggested the feature may help the tadpoles see eggs being dropped by mother frogs into the hole during feeding time.

Fully grown, the frogs are about as big as a golf ball. Uniquely, they feed mostly on vegetation, rather than insects and larvae.

"Frogs have been around for 350 million years, and have evolved to face so many habitat challenges," said Biju, who is known in India by the nickname "The Frog Man" and has discovered 89 of the 350 or so frog species known to be in the country.

Scientists said the work was crucial for both understanding the planet's biological diversity and raising awareness about the need for conservation. Already, Australia has seen the extinction of one frog species that brooded tadpoles in its stomach, while Central America recently lost its brightly colored Golden Toad.

"Species discoveries and rediscoveries ... can bring excitement and focus to animals like amphibians that, despite being the most threatened vertebrate group, are underrepresented in the media and scientific literature," said herpetologist Robin Moore, co-founder of the Washington, DC-based Amphibian Survival Alliance. "Wonder and inspiration tend to be more powerful motivators than despair."



Advertisements

Latest Tech & Science News

  • Panda mania hits Germany as Meng Meng, Jiao Qing arrive

    Tech & Science CTV News
    Germany was bracing for panda mania as furry ambassadors arrive from China on Saturday, destined for a new life as stars of Berlin's premier zoo. The pair, named Meng Meng and Jiao Qing, will be jetting in on a special Lufthansa cargo plane, accompanied by two Chinese panda specialists, the Berlin Zoo's chief vet and a tonne of bamboo. Source
  • Google to stop scanning Gmail for ad targeting

    Tech & Science CTV News
    Google said Friday it would stop scanning the contents of Gmail users' inboxes for ad targeting, moving to end a practice that has fueled privacy concerns since the free email service was launched. A Google statement said Gmail users would still see "personalized" ads and marketing messages but these would be based on other data, which may include search queries or browsing habits. Source
  • It's worth the drive to totality: perspectives from an eclipse chaser: Bob McDonald

    Tech & Science CBC News
    August 21st is going to be an insane day across the United States as millions of people gather along a thin line that stretches from coast to coast to watch the moon pass directly in front of the sun in a total solar eclipse. Source
  • Dutch invent phone app to stop kids texting on bikes

    Tech & Science CTV News
    In the bike-mad Netherlands, the national phone company is developing a smart way to stop kids texting while cycling -- a growing cause of teenage accidents. A new app from phone company KPN will block internet and phone signals to a cyclist's smartphone while they are in the saddle. Source
  • Facebook launches plan to combat online extremism

    Tech & Science CTV News
    U.S. social media giant Facebook launched a campaign in Britain on Friday to counter the spread of online extremism following warnings from Prime Minister Theresa May after four terror attacks in three months. Facebook said it would seek to educate charities and other organisations on how to fight hate speech, in the wake of recent terror attacks in Belgium, Britain and France. Source
  • Live Asian carp discovered near Lake Michigan

    Tech & Science CTV News
    TRAVERSE CITY, Mich. -- A live Asian carp has been discovered in a Chicago waterway about nine miles from Lake Michigan -- well beyond an electric barrier network designed to prevent the invasive fish that have infested the Mississippi River system from reaching the Great Lakes, officials said Friday. Source
  • B.C. woman can file class-action lawsuit against Facebook: Supreme Court

    Tech & Science Toronto Sun
    OTTAWA — The Supreme Court of Canada says a woman who wants to sue Facebook over its use of “sponsored stories” can pursue her case in British Columbia. Deborah Douez wants to file a class-action lawsuit against the social media giant over a now-defunct advertising format, which allegedly used her name and profile photo in ads endorsing a company for which she had clicked the “Like” button. Source
  • Is Tesla getting into the streaming music business?

    Tech & Science CTV News
    Electric carmaker Tesla said Thursday it was considering ways to enter music streaming amid a report it may launch a unique new service. The high-end carmaker, which already has a tie-up with streaming leader Spotify in some international markets, said it was aiming at ways to please drivers. Source
  • Solar eclipse in August raising worries about Ontario's power grid

    Tech & Science CTV News
    An astronomical delight this summer is going to pose a terrestrial problem. Operators of Ontario’s power grid are bracing for a sharp drop in electricity generated by solar panels during a summer solar eclipse coming Aug. Source
  • Total solar eclipse casts spotlight on rural Oregon town

    Tech & Science CTV News
    MADRAS, Ore. -- Just before sunrise, there's typically nothing atop Round Butte but the whistle of the wind and a panoramic view of Oregon's second-highest peak glowing pink in the faint light. But on Aug. Source