Emperor Penguin

 

Aptenodytes forsteri

Emperor penguins are the largest penguins, standing about 4 feet (1.2 meters) tall.

Photograph courtesy Giuseppe Zibordi/Michael Van Woert/
NOAA NESDIS, ORA

Map

Emperor Penguin Range

Fast Facts

Type:

Bird

Diet:

Carnivore

Average life span in the wild:

15 to 20 years

Size:

45 in (115 cm)

Weight:

Up to 88 lbs (40 kg)

Group name:

Colony

Size relative to a 6-ft (2-m) man:

Emperors are the largest of all penguins—an average bird stands some 45 inches (115 centimeters) tall. These flightless animals live on the Antarctic ice and in the frigid surrounding waters.

Penguins employ physiological adaptations and cooperative behaviors in order to deal with an incredibly harsh environment, where wind chills can reach -76°F (-60°C).

They huddle together to escape wind and conserve warmth. Individuals take turns moving to the group's protected and relatively toasty interior. Once a penguin has warmed a bit it will move to the perimeter of the group so that others can enjoy protection from the icy elements.

Emperor penguins spend the long winter on the open ice—and even breed during this harsh season. Females lay a single egg and then promptly leave it behind. They undertake an extended hunting trip that lasts some two months! Depending on the extent of the ice pack, females may need to travel some 50 miles (80 kilometers) just to reach the open ocean, where they will feed on fish, squid, and krill. At sea, emperor penguins can dive to 1,850 feet (565 meters)—deeper than any other bird—and stay under for more than 20 minutes.

Male emperors keep the newly laid eggs warm, but they do not sit on them, as many other birds do. Males stand and protect their eggs from the elements by balancing them on their feet and covering them with feathered skin known as a brood pouch. During this two-month bout of babysitting the males eat nothing and are at the mercy of the Antarctic elements.

When female penguins return to the breeding site, they bring a belly full of food that they regurgitate for the newly hatched chicks. Meanwhile, their duty done, male emperors take to the sea in search of food for themselves.

Mothers care for their young chicks and protect them with the warmth of their own brood pouches. Outside of this warm cocoon, a chick could die in just a few minutes. In December, Antarctic summer, the pack ice begins to break up and open water appears near the breeding site, just as young emperor penguins are ready to swim and fish on their own.

link: http://animals.nationalgeographic.com/animals/birds/emperor-penguin/

Adélie Penguin

 

Pygoscelis adeliae

Wings spread, this Adélie penguin waddles through an Antarctic colony. Its black tail gives it a tuxedo-like appearance.

Photograph by George F. Mobley

Map

Adélie Penguin Range

Fast Facts

Type:

Bird

Diet:

Carnivore

Average life span in the wild:

Up to 20 years

Size:

27.5 in (70 cm)

Weight:

8.5 to 12 lbs (4 to 5.5 kg)

Group name:

Colony

Did you know?

Adult Adélie penguins have been observed stealing rocks from their neighbors’ nests.

Size relative to a 6-ft (2-m) man:

Adélie penguins live on the Antarctic continent and on many small, surrounding coastal islands. They spend the winter offshore in the seas surrounding the Antarctic pack ice.

Adélies feed on tiny aquatic creatures, such as shrimp-like krill, but also eat fish and squid. They have been known to dive as deep as 575 feet (175 meters) in search of such quarry, though they usually hunt in far shallower waters less than half that depth.

Like other penguins, Adélies are sleek and efficient swimmers. They may travel 185 miles round-trip (about 300 kilometers) to procure a meal.

During the spring breeding season (in October), they take to the rocky Antarctic coastline where they live in large communities called colonies. These groups can include thousands of birds.

Once on land, Adélies build nests and line them with small stones. Though they move with the famed "penguin waddle" they are capable walkers who can cover long overland distances. In early spring, before the vast sheets of ice break up, they may have to walk 31 miles (50 kilometers) from their onshore nests to reach open water.

Male Adélie penguins help their mates rear the young and, without close inspection, the two sexes are nearly indistinguishable. They take turns sitting on a pair of eggs to keep them warm and safe from predators. When food is short, only one of the two chicks may survive. After about three weeks, parents are able to leave the chicks alone, though the offspring gather in groups for safety. Young penguins begin to swim on their own in about nine weeks.

http://animals.nationalgeographic.com/animals/birds/adelie-penguin/

Role of Skin Microbiota

Protective Role of Skin Microbiota Described

ScienceDaily (July 26, 2012) — A research team at the National Institutes of Health has found that bacteria that normally live in the skin may help protect the body from infection. As the largest organ of the body, the skin represents a major site of interaction with microbes in the environment. Although immune cells in the skin protect against harmful organisms, until now, it has not been known if the millions of naturally occurring commensal bacteria in the skin -- collectively known as the skin microbiota -- also have a beneficial role.

Using mouse models, the NIH team observed that commensals contribute to protective immunity by interacting with the immune cells in the skin. (Credit: © Vasiliy Koval / Fotolia)

Using mouse models, the NIH team observed that commensals contribute to protective immunity by interacting with the immune cells in the skin.

Their findings appear online on July 26 in Science.

The investigators colonized germ-free mice (mice bred with no naturally occurring microbes in the gut or skin) with the human skin commensalStaphylococcus epidermidis. The team observed that colonizing the mice with this one species of good bacteria enabled an immune cell in the mouse skin to produce a cell-signaling molecule needed to protect against harmful microbes. The researchers subsequently infected both colonized and non-colonized germ-free mice with a parasite. Mice that were not colonized with the bacteria did not mount an effective immune response to the parasite; mice that were colonized did.

In separate experiments, the team sought to determine if the presence or absence of commensals in the gut played a role in skin immunity. They observed that adding or eliminating beneficial bacteria in the gut did not affect the immune response at the skin. These findings indicate that microbiota found in different tissues -- skin, gut, lung -- have unique roles at each site and that maintaining good health requires the presence of several different sets of commensal communities.

This study provides new insights into the protective role of skin commensals and demonstrates that skin health relies on the interaction of commensals and immune cells. Further research is needed, say the authors, to determine whether skin disorders such as eczema and psoriasis may be caused or exacerbated by an imbalance of skin commensals and potentially harmful microbes that influence the skin and its immune cells.

The study was led by investigators in the laboratories of Yasmine Belkaid, Ph.D., at the National Institute of Allergy and Infectious Diseases, in collaboration with Julie Segre, Ph.D., at the National Human Genome Research Institute, and Giorgio Trinchieri, M.D., and Heidi Kong, M.D., at the National Cancer Institute. All three Institutes are NIH components.

Story Source:

The above story is reprinted from materials provided byNIH/National Institute of Allergy and Infectious Diseases.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

---

Journal Reference:

1. S Naik et al. Compartmentalized control of skin immunity by resident commensals. Science, 2012 DOI:10.1126/science.1225152

link: http://www.sciencedaily.com/releases/2012/07/120726153947.htm