Sunday 20 August 2017 News Updated at 01:08 PM IST
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A blue transgenic Taihei chrysanthemum, created by Japanese scientists by modifying two genes.
The blues of the chrysanthemum


A blue human is a cold, dead or sad human. We don’t want to be blue. And flowers don’t appear to, either. Less than 10% of 4,00,000 floral species bear blue flowers. Scientists and horticulturists have tried to force blueness upon flowers, but breeding and genetic engineering have not worked out, mainly because there are not many compatible plants with the genetic machinery to manufacture blueness.

Now Japanese scientists have finally created a true blue chrysanthemum - one that passes the strict colour standards of the Royal Horticultural Society (RHS). Chrysanthemums are usually pink, yellow or red. The scientists hope their methods, published July 26 in Science Advances, can be used to blue-ify other flowers, like roses.

"Plant species blooming blue flowers are relatively rare,” says Naonobu Noda, a plant biologist at the National Agriculture and Food Research Organisation in Japan who led the research. It took Naonobu and his colleagues years to create their blue chrysanthemum. They got close in 2013, engineering a 'bluer-coloured’ one by splicing in a gene from Canterbury bells, which naturally make blue flowers. The resulting blooms were violet. This time, they added a gene from another naturally blue flower called the butterfly pea.

Both of these plants produce pigments for orange, red and purple called delphinidin-based anthocyanins. Under a few different conditions, these pigments, which are sensitive to changes in pH, can start a chemical transformation within a flower, rendering it blue.

The additional gene did the trick. It added a sugar molecule to the pigment, shifting the plant’s pH and altering the chrysanthemum’s colour. The researchers confirmed the colour as blue by testing its wavelengths in the lab.

The rhythms of elephant seals
If you’re a beta northern elephant seal and you hear one sound, you might run. But when you hear another sound, you might scratch your head and wait to see what happens. And here’s why: In the rhythm and pitch of the first call, you recognise one voice as a familiar, more dominant male that you have fought with before.
But you can’t discern the other, modified call, according to a study published last month in Current Biology. This suggests that elephant seals are the only known mammals other than humans that can use rhythm to recognise and respond to other members of their species.

During breeding season, between December and March, elephant seals take a break from their lives at sea and congregate on the West Coast of USA. The males, called bulls, arrive first and fight to establish dominance. Winning males become alphas with a whole harem with which they can breed. Losers become betas, connecting with females only opportunistically, when the alphas aren’t around. At AÑo Nuevo State Park in California, USA, the researchers recorded calls from elephant seals up and down the hierarchy. Later, they returned to the beach with calls they had altered in the lab. They set up speakers a foot tall a few yards from the seals and played back the original and modified calls of alpha seals to beta seals.

The team found that the subordinate seals recognised the rhythm and pitch of the original dominant individual’s call and fled. But when the researchers manipulated the original call, sliding the pitch higher or lower or the rhythm faster or slower , the subordinate seals reacted to the modified calls just as they would to the calls of strangers: they waited to see what type of interaction would follow. This is the first study to experimentally demonstrate that a non-human mammal can use the rhythm of another’s voice to make decisions that affect survival.

Joanna Klein

The small brain lobes of giant squids

Giant squids, which roam the deep sea and grow bodies large enough to spoon a school bus, are the stuff of legend. Among the creature’s biggest claims to fame are its eyes. But the sophistication of the giant squid’s visual brain may not be equal with its eyes, says a paper published in Royal Society Open Science. A recent chance to study part of a giant squid brain up-close suggests that, compared with cephalopods that live in shallow waters, giant squids have a small optic lobe relative to their eye size. Also, the region in their optic lobes that integrates visual information with motor tasks is reduced, implying that giant squids don’t rely on visually guided behaviour. "This is the first time we get to know how the world might look like to a giant squid,” said Robyn Crook, an assistant professor of biology who was not involved in the study.

Steph Yin

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