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.
Congress leader Manishankar Aiyar attracted opposition BJP's ire today in Rajya Sabha when he said he was not interested in listening to speech of a BJP member on vote on account, prompting the Chair to adjourn the House amid uproar. During the Zero Hour, Deputy Chairman P J Kurien allowed Aiyar, who wanted to ask a question, to do so, which was opposed by BJP members. Kurien asked Aiyar whether he yielded to allow others to speak, to which he said he had no objection and he can ask his question later. As the House got ready to initiate discussion on Vote on Account, Kurien said, "Let us reduce the discussion to two hours from four hours," which was opposed by BJP members including Piyush Goyal who was given a chance to speak on Vote on Account. When it was agreed that discussion will take place as per schedule, Aiyar remarked he was not interested in listening to the speech by BJP member. "You had given me the chance to ask a question
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