Type: Prelims Only

Researchers have accidentally discovered living under the ice shelves of the Antarctic — in extremely cold and harsh conditions.

Life beneath the Antarctic

• Scientists have discovered sessile sponges — a pore bearing multicellular organism and other alien species — attached to the sides of rock beneath the ice sheets.
• The unidentified species are estimated to be related to sponges, ascidians (sea squirts), hydroids, barnacles, cnidarian or polychaete. All of these look like bristle worms.
• Scientists are yet to discover how these organisms access food.
• They would use Environment Deoxyribonucleic acid (e-DNA) technology in future to identify the organisms.

Organisms discovered

Sponges

• Sponges are the members of the phylum Porifera.
• They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.

Ascidians

• Ascidians, or sea squirts, are invertebrate chordates that belong to the earliest branch in the chordate phylum.
• Ascidians are found all over the world, usually in shallow water with salinities over 2.5%.

Hydroids

• Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish.
• Some hydroids such as the freshwater Hydra are solitary, with the polyp attached directly to the substrate.

Barnacles 

• Barnacles are a highly specialized group of crustaceans.
• A barnacle is a type of arthropod related to crabs and lobsters.

Cnidarians

• Cnidarians, also called coelenterate, any member of the phylum Cnidaria (Coelenterata), a group made up of more than 9,000 living species.
• Mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.

Now take this chance to revise your biology basics on various phyla. It will be beneficial for state PSC exams. UPSC has also begun puzzling us on core biology questions.

Defying old theories

• The discovery has left many of them baffled for it contradicts earlier theories of non-survival of life in such extreme conditions.
• Until now, scientists believed that sea life decreased with an increase in the depth of the Antarctic ice floor.

Crystals are normally rigid, stiff structures, but researchers from the University of Hyderabad have shown how crystals can be sliced and even bent using atomic force microscopy. They have named this technique as “mechanophotonics”.

The newscard discusses an out of the box technology which if brought to reality in practical use, can create immense disruptions in the technology market.

Manipulating light through crystals

• Manipulating them with precision and control comes in very useful in the field of nanophotonics, a qualitative, emerging field.
• The aim is to go beyond electronics and build-up circuits driven entirely by photons (light).

If the technique can be successfully developed, this can achieve an unprecedented level of miniaturisation and pave the way to all-optical-technology such as pliable, wearable devices operated by light entirely.

What Indian researchers have achieved?

: Bending light path

• Light, when left to itself moves along straight paths, so it is crucial to develop materials and technology that can cause its path to bend along what is required in the circuits.
• This is like using fibre optics, but at the nanoscale level using organic crystals.
• The Hyderabad group has demonstrated how such crystals can be lifted, bent moved, transferred and sliced using atomic force microscopy.

: How?

• Researchers add a crucial piece to the jigsaw puzzle of building an “organic photonic integrated circuit” or OPIC.
• Generally, millimetre- to centimetre-long crystals were bent using hand-held tweezers.
• This method lacks precision and control. Also, the crystals used were larger than what was required for miniaturisation.
• The atomic force microscopy (AFM) cantilever tip could be used to lift a crystal, as crystals tend to stick to the tip due to tip–crystal attractive forces.
• Thus they demonstrated the real waveguiding character of the crystal lifted with a cantilever tip.

In 2014, for the first time, the group led by Rajadurai Chandrasekar of the Functional Molecular Nano/Micro Solids Laboratory in University of Hyderabad demonstrated that tiny crystals could be lifted and moved with precision and control using atomic force microscopy.

What is Atomic Force Microscopy (AFM)?

• AFMs are a type of electron microscope used for the observation at an atomic level.
• It is commonly used in nanotechnology.
• The AFM works by employing an ultra-fine needle attached to a beam.
• The tip of the needle runs over the ridges and valleys in the material being imaged, “feeling” the surface.