Showing posts with label biology. Show all posts
Showing posts with label biology. Show all posts

Wednesday, 1 February 2017

SCIENCE | 'Little Fish Fireworks' On Display Underwater

Representational image

Have you heard of bioluminescence? Well, according to BBC Earth, it is 'one of nature's most dazzling underwater displays.' And fortunately for us, a BBC film crew has managed to film this phenomenon as a form of self- defence.

The ocean- dwelling ostracods are animals that are known to give off light when they are disturbed. These organisms produce the chemicals luciferin and luciferase. which emit light when they combine. This process is called bioluminescence, an adaptation that makes animals visible in the pitch black darkness in the deepest regions of the sea.

To exhibit why organisms are able to give off light, ostracods were put into a tank along with cardinal fish, which, by the way, are plankton- eaters. The crew then observed that when a cardinal fish swallowed an ostracod, the latter emitted a burst of light, compelling  the fish to spit it out.

Physicist and BBC presenter Helen Czerski called this dazzling display as a 'little fish firework'.

Catch the light- emitting ostracods in action here:


Friday, 27 January 2017

SCIENCE | The Newfound Secret Shortwings of The Sahyadris



Naturalists exploring the "sky islands" of The Sahyadri have stumbled upon some of its well kept secrets nestled in the forests of some of its highest peaks, confirming the founding of two new endemic genera and a new species of songbird.

The research team, comprising of V. V. Robin, Sushma Reddy, C. K. Vishnudas, Pooja Gupta, Frank E. Rheindt, Daniel M. Hooper and Uma Ramakrishnan, has published the reports of the undertaking in the latest issue of BMC Evolutionary Biology. 

The reports suggest that the team has designated two new genera: one, the Western Ghats shortwings identified under Sholicola (closely related to flycatchers), and second, the laughing thrushes as Montecincla (closely related to babblers). The newly described Sholicola ashambuensis is confined to the Agasthyar Malai mountain ranges.

The species in the Montecincla genera include Montecincla jerdoni, Montecincla cachinnans, Montecincla fairbanki and Montecincla meridionalis  and belong to the genus Montecincla. 

Sholicola major and Sholicola albiventris belong to Sholicola genus.

Mr. V. V. Robin, a member of the research team, stated,"Though many people had noted some differences in feather patterns across populations in different mountain tops or 'sky islands', they were still considered a single species. It wasn’t until we had genetic data that we realised the traditional story was wrong."

The taxonomy of the birds also posed a challenge to the researchers. "What used to be called Western Ghats shortwings actually turned out to be flycatchers, and what used to be called laughing thrushes are actually more closely related to other babblers," Mr. Robin added.

"When we reconstructed their genetic relationships, it was clear that these two lineages were very different from the genera in which they were previously placed," Ms. Reddy said.

Another lucky break was the discovery of old forgotten specimens in the Trivandrum Natural History Museum. “They were locked away in a cabinet and forgotten for nearly 100 years. When I found them in 2009, I never thought that it would lead to the discovery of a new species!” Mr. Vishnudas said.

"For Western Ghats, already known for its rich and unique biodiversity, we have just increased the number of bird species found nowhere else in the world and each of these now have narrower distribution," said Ms. Ramakrishnan.

The discontinuous patches of forests on the highest peaks of The Westers Ghats are home for these birds; and these happen to be some of the most vulnerable parts of the ecosystem crumbling under the increasing pressure from human activities and climate change. However, Ms. Ramakrishnan seemed hopeful of the fact that the knowledge of the distinct evolution of these birds, and of ecology would be helpful in increasing conservation efforts.