Penguin populations in Antarctica surged
during the Little Ice Age - a cold period between 1500 and 1800 AD, a
new study suggests. Past studies have suggested penguins actually
thrive when the climate is relatively warm, since cold climates increase
sea-ice extent, which makes it difficult for the birds to access their
beach colonies and food-rich waters. Researchers Liguang Sun and
Zhouqing Xie, from the University of Science and Technology of China,
analysed how the populations of Adelie penguins changed over the past
700 years in the Ross Sea, a region in Antarctica that is at a higher
latitude than previous study sites. They analysed sediment samples from
multiple depths for cholesterol and cholestanol, which are bio-markers
indicating soil contamination by animal feces, 'LiveScience' reported.
On the basis of variation in the markers, researchers divided up the
timeline into four time periods. The bio-markers suggested penguin
populations boomed during Period II (1490 to 1670), declined
significantly during Period III (1670 to1950) and increased steadily
since then in Period IV (1950 to present). The amounts of vegetation
corroborated the penguin data. Antarctic algae require a lot of
nutrients from penguin droppings to thrive, whereas penguin trampling
endangers lichens, the report said. The evidence shows that algae
abundances increased and decreased along with the penguin populations,
but lichen abundances showed the opposite trend. The summer
temperatures during the Little Ice Age were about 2 degrees Celsius
colder than the previous 200 years — this chilly climate promoted more
sea-ice extent, which would normally be detrimental to penguins.
Legendary playback singer Manna Dey, who mesmerised generations of listeners with his inimitable voice for over five decades with hits like 'ay mere pyara watan', 'laaga chunri me daag' and 'poocho na kaise', died at a hospital here today at the age of 94 after prolonged illness. Dey, who was in and out of Narayana Hrudayalaya Hospital in the last five months for respiratory and renal problems, died of cardiac arrest with his daughter Shumita Deb and son-in-law Jnanranjan Deb by his bedside when the end came at 3.50 AM. The condition of Dey, who had made Bangalore his home for the last many years, deteriorated since yesterday afternoon, hospital spokesman Vasuki said. With the demise of Dey, the void has become complete in the famous quartet of singers Rafi, Mukesh, and Kishore Kumar, who dominated the Hindi music industry from 1950s to 1970s. The mortal remains of Dey, whose unique voice lent a rare dimension to his persona, were cremate...
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