Penguins and taste, new research


Thuis video is called Funny and cute penguin videos compilation.

From the Australian Broadcasting Corporation:

Poor taste penguins lack umami gene

Rachel Sullivan

Tuesday, 17 February 2015

Penguins can’t appreciate the delicate flavours of the seafood they catch thanks to a lack of taste.

New research published today in Current Biology reveals that penguins don’t have the genes that encode three of the five basic tastes – sweet, bitter, and umami (a savoury flavour), although they are genetically capable of detecting salty and sour tastes.

The study, led by Dr Huabin Zhao from Wuhan University, looked at the recently sequenced genomes of Adelie penguins (Pygoscelis adeliae) and emperor penguins (Aptenodytes forsteri) and 14 other bird species.

They found that while many other birds, such as chickens, finches and Amazon parrots have also lost the ability to taste sweet flavours, unlike penguins they are still able to detect bitter and umami tastes.

“Our results strongly suggest that the umami and bitter tastes were lost in the common ancestor of all penguins, whereas the sweet taste was lost earlier,” explains study co-author Dr Jianzhi Zhang from the University of Michigan.

He says it’s a puzzling finding.

“Penguins eat fish, so you would guess that they need the umami receptor genes, but for some reason they don’t have them.”

Adding to the puzzle is that taste is a powerful indicator of whether a potential food item is good enough to eat.

“In general, a sour taste helps detect spoiled food and bitter taste helps detect toxic food,” Zhang says. “Presumably, penguins cannot use taste to detect toxins … but we don’t know if penguins have other means of detecting toxins.”

Temperature sensitivity

Zhang says that while the research team doesn’t yet have a definitive answer to why penguins are so lacking in taste, they do have some ideas.

Penguins evolved in the chilly Antarctic, and the taste receptors for sweet, umami and bitter tastes (but not salty or sour tastes) are inactive at lower temperatures. It is likely that since they wouldn’t have worked anyway their loss along the evolutionary pathway would have had minimal impact.

Many species of penguins have since spread out into warmer climates. However, Zhang says “if ancestral penguins had lost the receptor genes for the three tastes while in the Antarctic, the genes and tastes cannot be regained even when some migrated away.”

In addition, anatomical studies have shown that penguin tongues seem to lack taste receptors – even for salty and sour flavours. Instead they are covered in stiff, horny bristles designed to help catch and hold their slippery prey, which they then swallow whole, so they may not have much interest in how their food tastes anyway.

But Zhang says he is not sure that penguins completely lack taste buds pointing to the possibility that they yet might be found in the tissues of the pharanx or elsewhere in the palate.

Sweet exception

Interestingly, in nectar-loving hummingbirds that have also lost the genes encoding sweet receptors, the umami receptor has been repurposed to detect the sweet tastes of the food source they depend on.

Zhang says that a similar repurposing hasn’t happened in penguins.

“The sweet and umami receptors have a common ancestry and are similar in structure so it is possible for the hummingbird umami receptor to be repurposed to detect sweet,” he says.

“However, the sour and salty receptors are structurally completely different from sweet and umami receptors: There is no way that they can be repurposed to sense sweet or umami.”

Adelie penguins on webcam this week


This video says about itself:

Adelie Penguins of Paulet Island, Antarctica

30 dec. 2011

Paulet Island, located near the Antarctic Peninsula in the northwest Weddell Sea, is home to more than 100,000 breeding pairs of Adelie penguins. The island is a small circular volcanic cone, about one mile in diameter with rocky slopes rising more than 1,100 feet above the shoreline.

Cobble beaches are favorite napping locations for Weddell seals, which you’ll see in this video.

Adelie penguins pop in and out of the surf as they return to shore throughout the day. They spend some time drying off and preening on the upper beaches before making their way to the nesting locations. In some cases, this is a rather difficult journey over loose scree slopes to the uppermost ledges of the volcanic cone.

Snow fields are used by the penguins to travel back and forth from a freshwater lake at the center of the island. This lake was once used by members of Dr. Otto Nordenskjold‘s 1901-1904 Swedish Antarctic Expedition to survive being stranded on the island. A stone hut and burial marker remain today, but the hut is now prime roosting territory for Adelie penguins.

From the Cornell Lab of Ornithology in the USA today:

This Week Only: Watch Penguins Live in Antarctica

Don’t miss this live visit to an Adelie Penguin colony in Antarctica! We’ll be hosting a Q&A with an oceanographer and a penguin scientist at Palmer Station, Antarctica. They’ll take you on a virtual tour of a nearby penguin island, and you’ll be able to ask questions via live chat for the scientists to answer.

We’re hosting two 1-hour live sessions: the first is on Thursday, Jan. 29, at 1:00 p.m. Eastern time. The second is on Saturday, Jan. 31, at 11:00 a.m. Eastern time. To watch, just bookmark this link and join us live for one or both sessions!

Antarctic gentoo penguins, video


The Cornell Lab of Ornithologyy in the USA writes about this 4 December 2014 video:

December is just about the warmest time of year for a Gentoo Penguin, and time for them to get busy raising chicks amid the rock and ice of Antarctica and its islands. Watch this video and enjoy a penguin‘s eye view of a breeding colony on the Antarctic Peninsula.

Stay Tuned: After the holidays, join us for two special live-streamed video conversations with scientists at a penguin colony in Antarctica. They’re scheduled for Jan. 29 and Feb. 3 (weather depending). Bookmark this link, and we’ll have more details for you in January.

Will little penguins survive climate change?


This video from Australia is called Little Penguins Return to the Open Ocean.

From Wildlife Extra:

Penguins‘ personalities could help them cope with climate change

According to a new study, the individual personalities of birds could be one of the key factors that improve its chances of coping with environmental stressors, especially in times of rapid weather changes due to climate change.

John Cockrem from the Institute of Veterinary, Animal and Biomedial Sciences at Massey University in New Zealand was behind the study. He studied differences in levels of the stress hormone corticosterone in Little Penguins when they were exposed to stressful stimulus. He found that there was ‘considerable individual variation in corticosterone responses’.

“Corticosterone responses and behavioural responses to environmental stimuli are together determined by individual characteristics called personality,” Cockrem explains. “Birds with low corticosterone responses and proactive personalities are likely to be more successful (have greater fitness) in constant or predictable conditions, whilst birds with reactive personalities and high corticosterone responses will be more successful in changing or unpredictable conditions.”

Birds are thought to be particularly at risk from the effects of climate change, and these findings could be helpful in predicting the adaptability of species of birds as they face a ‘new normal’.

African penguin language, new research, videos


This video is called African Penguins go for a swim – Mountain of the Sea – BBC.

From Salon.com:

Thursday, July 31, 2014 05:12 PM +0200

How to talk to African penguins, in 6 simple videos

Researchers identified distinct calls used to express loneliness, anger, hunger and ecstasy

Lindsay Abrams

After 104 days of careful observation, researchers at the University of Turin, in Italy, think they’ve finally figured out what African penguins are “talking” about. Based on the sounds and behaviors of a colony of 48 captive penguins at the Zoom Torino zoo, the team identified six distinct vocalizations used by adults and juveniles to express just about everything that needs saying: from loneliness, to anger, to mutually experienced ecstasy.

“Vocal communication allows us to understand the many different aspects of the biology of this species,” lead author Livio Favaro explained to the Guardian. “Penguins have less sophisticated vocal mechanisms compared to song birds, but they have very sophisticated mechanisms to encode information in songs.”

The findings, written up in the journal PLOS ONE, are accompanied by a set of videos illustrating the calls. Watch them a few times, and you, too, can become fluent in the endangered species‘ language.

Contact calls are emitted by individual penguins when out of sight from their colony or partner:

The agonistic call is often emitted during fights or as a warning for other penguins to stay away. The birds stand up and stretch their necks out toward the target of their aggression:

In the ecstatic display song, the longest and loudest of African penguin calls, the birds spread their feet, stretch their neck and face upward and hold their wings out horizontally to advertise their availability to potential mates. It kind of sounds like a donkey, the researchers note, which is how the African penguin earned the nickname “jackass”:

The mutual ecstatic song is sung when mates finally get together. Partners, the researchers observed, “often emitted this call simultaneously, overlapping in a duet” — and are known to make the sound when others attempt to intrude on their twosome:

Begging moans, a newly described call, are only emitted by juveniles, and only until they’re either fed, or their parents go away:

The youngest of penguins, those under 3 months old, will emit long series of these high-pitched begging peeps for minutes on end until their parents regurgitate some food for them:

All penguin species are continuing to be at risk from habitat degradation and loss a new study finds: here.

Giant fossil penguin discovery in Antarctic


This video says about itself:

5 October 2010

Scientists have unearthed fossilized remains of a five-foot-tall (150-centimeter-tall) penguin in present-day Peru. The 36-million-year-old fossil sheds light on bird evolution, according to National Geographic grantee Julia Clarke. Video produced by the University of Texas at Austin.

From New Scientist:

Extinct mega penguin was tallest and heaviest ever

01 August 2014 by Jeff Hecht

Forget emperor penguins, say hello to the colossus penguin. Newly unearthed fossils have revealed that Antarctica was once home to the biggest species of penguin ever discovered. It was 2 metres long and weighed a hefty 115 kilograms.

Palaeeudyptes klekowskii lived 37 to 40 million years ago. This was “a wonderful time for penguins, when 10 to 14 species lived together along the Antarctic coast”, says Carolina Acosta Hospitaleche of the La Plata Museum in Argentina.

She has been excavating fossil deposits on Seymour Island, off the Antarctic peninsula. This was a warmer region 40 million years ago, with a climate like that of present-day Tierra del Fuego, the islands at the southern tip of South America.

The site has yielded thousands of penguin bones. Earlier this year, Acosta Hospitaleche reported the most complete P. klekowskii skeleton yet, although it contained only about a dozen bones, mostly from the wings and feet (Geobios, DOI: 10.1016/j.geobios.2014.03.003).

Now she has uncovered two bigger bones. One is part of a wing, and the other is a tarsometatarsus, formed by the fusion of ankle and foot bones. The tarsometatarsus measures a record 9.1 centimetres. Based on the relative sizes of bones in penguin skeletons, Acosta Hospitaleche estimates P. klekowskii was 2.01 meters long from beak tip to toes.

Its height will have been somewhat less than its length owing to the way penguins stand. But it was nevertheless larger than any known penguin.

Fossil and present penguins

Emperor penguins can weigh 46 kilograms and reach lengths of 1.36 metres, 0.2 metres above their standing height. Another extinct penguin used to hold the height record, at around 1.5 metres tall.

P. klekowskii‘s tarsometatarsus “is the longest foot bone I’ve ever seen. This is definitely a big penguin,” says Dan Ksepka at the Bruce Museum in Greenwich, Connecticut. However, he cautions that the estimate of its length is uncertain because giant penguins had skeletons “very differently proportioned than living penguins”.

Larger penguins can dive deeper and stay underwater longer than smaller ones. A giant like P. klekowski could have stayed down for 40 minutes, giving it more time to hunt fish, says Acosta Hospitaleche.

Journal reference: Comptes Rendus Palevol, DOI: 10.1016/j.crpv.2014.03.008

New biosphere reserve in Argentina


This video is called Península Valdés, Argentina.

From Wildlife Extra:

A vast coastal wildlife haven in Argentina declared a Biosphere Reserve

Four million acres of wildlife-rich land in southern Argentina has been declared a Biosphere Reserve by UNESCO.

Península Valdés is situated on a rugged peninsula on the Atlantic coast of Patagonia in the Chubut Province, and is teeming with wildlife.

It has the largest breeding colony of southern elephant seals in South America and supports more than 70,000 pairs of Magellanic penguins, over 10,000 South American sea lions, cormorants, gulls, terns, and nearly 4,000 southern right whales. On land the peninsula sustains over 4,000 guanacos and some of the highest densities of maras and Darwin’s rheas in Patagonia.

The new reserve includes a previously unprotected area known as Punta Ninfas, where large numbers of elephant seals, South American sea lions, imperial cormorants, terns and Magellanic penguins live.

This area is under threat from three nearby large cities and uncontrolled access by people using off-road vehicles. The new Biosphere designation draws attention to the urgent need for ensuring the protection of wildlife here.

“Península Valdés is one of the great natural wonders of Latin America with greater concentrations of wildlife than any other area on the entire coast of Patagonia,” said WCS President and CEO Cristián Samper.

“Making this incredible area region a UNESCO Biosphere Reserve is the culmination of years of hard work by many great partners.”