Naturebytes

The world of honeybees

The secret to becoming a queen

You are what you eat” is a common adage among humans, but a new study explains why it might be more apt for honeybees. In a paper published in PLOS Genetics, researchers found specific molecules in the pollen and honey mixture that honeybee larvae feed on cause physical changes that determine whether females develop into long-living, reproductive queens or the mostly sterile workers that nourish larvae and collect food. Researchers have long known that these differences are not determined at birth but rather are a product of diet. Larvae that eat royal jelly, a substance secreted by the glands of nurse bees, develop into queens, while those that feed on a combination of pollen and honey called bee bread become workers. Previous research focused on the role of the protein and sugar-rich royal jelly in caste development, but this study found a new mechanism: small molecules in plants called microRNA. This information could provide new insight into the mysterious trend of rising honeybee deaths in the past decade, which could have a large impact on agriculture.


Living underground

Western Ghats’ new frog

A collaborative study by the Centre for Cellular and Molecular Biology (CCMB), American Museum of Natural History, and Nature Environment and Wildlife Society has discovered a new species of frog in the Western Ghats. The species is named Nasikabatrachus bhupathi (N bhupathi) in memory of late Dr S Bhupathy, a noted herpetologist. Measuring around five cm, N bhupathi is a burrowing species which spends most of its life underground, only surfacing for a few days each year during the northeast monsoon, to mate. “Explosive breeding is a characteristic of the species. The males come close to the surface and call. They call in synchrony and the entire habitat echoes of the call, but you cannot spot the calling frog. They might even be calling from right under your feet and yet, it can be very difficult to trace them,” says Karthikeyan Vasudevan of CCMB.

N bhupathi belongs to the genus Nasikabatrachus, of which there is only one other member. Both the species are endemic to the Western Ghats. When its sister species, the purple frog, Nasikabatrachus sahyadrensis was discovered in 2003, it was hailed as a ‘once in a century find’. “With the addition of the new species, the two surviving species of frogs are relics of the ancient past, when our landmass broke away from Africa and proceeded to collide with Asia. The relatives of Nasikabatrachus are now surviving in Seychelles Island — another breakaway landmass of Gondwana,” adds Karthikeyan.

Source of nutrients

Using toxic algal blooms as food

Toxic algal blooms, which can be seen covering ponds and lakes, happens due to a rapid growth of algae in the waterbody. Since some of these algae produce toxins harmful to humans and other animals, toxic algal blooms generally lead to a decrease in the amount of fish in the water and life surrounding it. Now, scientists from Indian Institute of Technology, Roorkee are trying to use the toxic algal blooms as sources of nutrients for useful microalgae, like Chlorella pyrenoidosa, a freshwater algae that has been used widely in traditional Chinese medicine for a long time, and in recent times, emerged as a leading candidate for the production of biodiesels. The scientists used various methods to prepare the toxic algae and microalgae mix; including using a combination of acid and alkali and using an autoclave and microwave. The tests revealed the toxic algae to be excellent source of nutrients for the microalgae. Using the acid/alkali combination, the microalgae grown showed an increase in the lipid content, which boosts the microalgae’s biodiesel output. The study not only allows efficient biodiesel production, but also addresses the problem of toxic algal blooms.


Documentary

DamNation

Made over the course of three years, DamNation talks about the environmental impacts of dams on the surroundings and wildlife. It also looks at restoring valuable river ecosystems and emphasises that this is worth losing the benefits we currently get from hydroelectric power generation. While the documentary focuses on the ecological cost of two centuries of American dam building, the impacts of dams on the environment is universal. To watch the documentary, visit www.damnationfilm.com.


Problem solving

Copy when young

Otters can learn how to solve puzzles by watching and copying each other, new research shows. Scientists created a series of puzzles baited with food, and found smooth-coated otters watched and copied each other’s problem-solving techniques — with young otters more likely to copy than their parents. But another species — Asian short-clawed otters — showed no sign of copying each other. According to Dr Neeltje Boogert of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus in Cornwall, the results suggest that smooth-coated otters adopt a ‘copy when young’ strategy. The offspring in the study learned to solve the puzzles much quicker than their parents — six times faster than their parents, Dr Neeltje added.


Adaptation strategy

The puzzle of sea snakes with jet-black skin

There’s something odd about turtle-headed sea snakes. It is not their name, or that they give live birth instead of laying eggs, or that they paddle more than they slither. It’s their skin. For years, researchers noticed that the aquatic snakes living in waters near human activity had jet-black skin, but most others, in more pristine waters, were speckled or banded. “It’s always been a puzzle,” said Richard Shine, an evolutionary ecologist at the University of Sydney, Australia who has been studying sea snakes for decades. But now, in a recent report published in Current Biology, Richard and his colleagues suggested that the varied colouration of sea snakes is probably an adaptation that helps them deal with pollution. It is like the moths in Europe that swapped speckled for black wings during the Industrial Revolution, evading hungry birds by blending in with coal dust. Only, rather than camouflage, black sea snake skin may act more like a pollution trap collecting heavy metals absorbed by the snakes and then cleaning them out as the skin is shed.