Wikipedia:Main Page history/2020 December 30b

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From today's featured article

Neutrophil (right) engulfing anthrax bacteria (left)

The immune system is a network of biological processes that protects an organism against disease. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinters, distinguishing them from the organism's own healthy tissue. Many species have two major subsystems of the immune system. The innate immune system provides a preconfigured response to broad groups of situations and stimuli. The adaptive immune system provides a tailored response to each stimulus by learning to recognize molecules it has previously encountered. Both use molecules and cells to perform their functions. Humans have sophisticated defense mechanisms, including the ability to adapt to recognize pathogens more efficiently. Adaptive (or acquired) immunity creates an immunological memory leading to an enhanced response to subsequent encounters with that same pathogen. This process of acquired immunity is the basis of vaccination. (Full article...)

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Did you know ...

Black-on-black ware pot from San Ildefonso Pueblo

... that black-on-black ware (example pictured) has been created by generations of Puebloan Native American ceramic artists in Northern New Mexico?
... that Soetran was nicknamed the "Clove Governor" after he obligated families in Papua to cultivate cloves?
... that Great American Bank, based in San Diego, was the first savings and loan association founded in Southern California?
... that the diaries of Lady Lacoste, a 19th-century philanthropist from Montreal, give historians a rare look into how emotions impacted the lives of women in her social class?
... that the Atlantic dancing shrimp is often associated with sea urchins or sea anemones?
... that pioneering lesbian columnist Deb Price's same-sex wedding announcement in The Washington Post was one of the first in a major national newspaper?
... that in a pre-game ceremony before the last game of the 1972 ice hockey Summit Series, the Canadian delegation presented a totem pole to the Soviet Union?
... that Scottsdale, Arizona, repealed its ban on dancing so that the Safari Hotel could open a nightclub?

In the news

COVID-19 pandemic: Disease; Virus; By location; Impact; Vaccines; Portal

The EU (blue) and the UK (orange)

A magnitude 6.4 M_w earthquake strikes Petrinja, Croatia, killing seven people.
The European Union and the United Kingdom (map shown) reach an agreement governing their relationship after Brexit.
The closest great conjunction between Jupiter and Saturn since 1623 occurs.
The Chang'e 5 sample-return mission returns lunar material to Earth.

On this day

December 30: Rizal Day in the Philippines (1896)

Arroyo Seco Parkway

999 – In Ireland, the combined forces of Munster and Meath crushed a rebellion by Leinster and Dublin.
1460 – Wars of the Roses: At the Battle of Wakefield, Lancastrian forces destroyed the Yorkist army and killed Richard of York at Sandal Magna in West Yorkshire, England.
1906 – The All-India Muslim League, a political party in British India that developed into the driving force behind the creation of Pakistan as a Muslim state on the Indian subcontinent, was founded in Dhaka.
1940 – The Arroyo Seco Parkway (pictured), one of the first freeways built in the U.S., connecting downtown Los Angeles with Pasadena, California, was officially dedicated.
2000 – A series of bombings occurred around Metro Manila in the Philippines, killing 22 people and injuring around 100 others.

Bernard Gui (d. 1331)
Sebastián Kindelán y O'Regan (b. 1757)
C. Harold Wills (d. 1940)

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Today's featured picture

The llama (Lama glama) is a domesticated South American camelid, widely used as a meat and pack animal by Andean cultures since the pre-Columbian era. A full-grown llama can reach a height of 1.7 to 1.8 metres (5 ft 7 in to 5 ft 11 in) at the top of the head, and can weigh between 130 and 200 kilograms (290 and 440 lb). At birth, a baby llama (known as a cria) can weigh between 9 and 14 kilograms (20 and 31 lb). Llamas typically live for 15 to 25 years, with some individuals surviving 30 years or more. This photograph shows a dam (female llama) and her cria at Laguna Colorada in Eduardo Avaroa Andean Fauna National Reserve, Bolivia.

Photograph credit: Kallerna

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