Science Briefs:


New facial-recognition system to track lemurs

Researchers in the US have developed a computer-assisted recognition system that can identify individual lemurs (above) in the wild through their facial characteristics.

LemurFaceID, which identifies individuals based on photos, allows researchers to build a database for long-term research on the species.

Dr Rachel Jacobs, a biological anthropologist at the George Washington University's Centre for the Advanced Study of Human Paleobiology and who was involved in the system's development, said the method could aid in evolutionary studies and conservation efforts.

The software could help to create records of how many individual lemurs there are in populations and what kind of social system they live in. It could also help to track trafficked lemurs if they are taken from the wild, said Dr Jacobs, in a statement by George Washington University.

Traditional methods require researchers to trap and physically tag them, but LemurFaceID is non-invasive, fast, cost-effective and accurate, she said.

The researchers hope the software can serve as a model for tracking other species and, in some cases, potentially replace physically tagging animals.

"We think this method could be applied to studies of species that have similar variation in hair and skin patterns, such as red pandas and some bears, among others," Dr Jacobs said.

Lemurs were named the world's most endangered group of mammals in 2012.

Hear this for gene therapy

Gene therapy delivered by a benign virus enabled deaf lab mice to hear for the first time, researchers said, offering hope for people with genetic hearing impairments.

The breakthrough could pave the way for gene-based treatments, they reported in two studies published in the journal Nature Biotechnology.

Genetic hearing disorders affect some 125 million people worldwide, according to the World Health Organisation.

In the first study, Associate Professor Konstantina Stankovic from Harvard Medical School and her colleagues used a harmless virus to transport - deep into the mouse ear - a gene that can fix a specific form of hereditary deafness.

Previous attempts had failed, but this time the viral package was delivered to the right address: the so-called outer hair cells that "tune" the inner ear to sound waves.

The technique bestowed hearing and balance "to a level that's never been achieved before", Dr Gwenaelle Geleoc, a researcher at the F.M. Kirby Neurobiology Centre at Boston Children's Hospital, said.

"Now you can whisper, and the mice can hear you."

In the second study, a team led by Dr Geleoc used the same viral courier to treat mice with a mutated gene responsible for Usher syndrome, a rare childhood genetic disease that causes deafness, loss of balance and, in some cases, blindness.

The virus carried a normal version of the same gene to damaged ear hair cells soon after the mice were born.

The results far exceeded anything to date: 19 of 25 treated mice heard sounds quieter than 80 decibels. A few of the mice could hear sounds as soft as 25 to 30 decibels - roughly equivalent to whispering.

Normal human conversation is about 70 decibels.


Quick fossil rebound after mass extinction

Fossils, including sharks, sea reptiles and squid-like creatures dug up in Idaho in the US reveal a marine ecosystem thriving relatively soon after Earth's worst mass extinction, contradicting the long-held notion that life was slow to recover from the calamity.

Scientists recently described the surprising fossil discovery showing creatures flourishing in the aftermath of the worldwide die-off at the end of the Permian Period about 252 million years ago that erased roughly 90 per cent of species.

The fossils of about 30 species unearthed in Bear Lake County near the Idaho city of Paris showed a quick and dynamic rebound in a marine ecosystem.

The Permian die-off occurred 251.9 million years ago. The Idaho ecosystem flourished 1.3 million years later, "quite rapid on a geological scale", said paleontologist Arnaud Brayard of France's University of Burgundy - Franche-Comte.

The cause of the mass extinction is a matter of debate. But many scientists attribute it to colossal volcanic eruptions in northern Siberia that unleashed large amounts of greenhouse and toxic gases, triggering severe global warming and big fluctuations in oceanic chemistry, including oxygen deficiency and acidification.

The researchers found bones from what could be the earliest-known ichthyosaur, a dolphin-like marine reptile group that prospered for 160 million years, or a direct ancestor.

"The Early Triassic is a complex and highly disturbed epoch, but certainly not a devastated one as commonly assumed, and this epoch has not yet yielded up all its secrets," Dr Brayard said.


Compiled by Samantha Boh

A version of this article appeared in the print edition of The Straits Times on February 24, 2017, with the headline 'Science Briefs'. Print Edition | Subscribe